v4k-git-backup/engine/v4k.h

/* game framework.
*  - rlyeh, public domain
*
* ## V4K License
*
* This software is available under 3 licenses. Choose whichever you prefer.
* ------------------------------------------------------------------------------
* ALTERNATIVE A - Public Domain (https://unlicense.org/)
* ------------------------------------------------------------------------------
* This is free and unencumbered software released into the public domain.
*
* Anyone is free to copy, modify, publish, use, compile, sell, or distribute this
* software, either in source code form or as a compiled binary, for any purpose,
* commercial or non-commercial, and by any means.
*
* In jurisdictions that recognize copyright laws, the author or authors of this
* software dedicate any and all copyright interest in the software to the public
* domain. We make this dedication for the benefit of the public at large and to
* the detriment of our heirs and successors. We intend this dedication to be an
* overt act of relinquishment in perpetuity of all present and future rights to
* this software under copyright law.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
* ------------------------------------------------------------------------------
* ALTERNATIVE B - MIT-0 (No Attribution clause)
* ------------------------------------------------------------------------------
* Permission is hereby granted, free of charge, to any person obtaining a copy of this
* software and associated documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the rights to use, copy, modify,
* merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
* ------------------------------------------------------------------------------
* ALTERNATIVE C - Zero BSD License (https://opensource.org/licenses/FPL-1.0.0)
* ------------------------------------------------------------------------------
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
* INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
* LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
* OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
* PERFORMANCE OF THIS SOFTWARE.
*
* ## License: Contributed Code ------------------------------------------------
*
* Dear Contributor,
*
* In order to ensure this project remains completely free and unencumbered by
* anyone's copyright monopoly, it is advisable that you dedicate your code-base
* contributions to the three licensing terms above. This removes any possible
* ambiguity as to what terms somebody might have thought they were contributing
* under, in case of a future dispute. These concerns are not unique to public
* domain software. Most large, established open-source projects have a
* Contributor License Agreement (CLA) process, of varying degrees of formality.
*
* Please add yourself to the list below before contributing.
* Thanks.
*
* --
*
* "I dedicate any and all copyright interest in this software to the three
* license terms listed above. I make this dedication for the benefit of the
* public at large and to the detriment of my heirs and successors. I intend
* this dedication to be an overt act of relinquishment in perpetuity of all
* present and future rights to this software under copyright law."
*
* Author (name)              I agree (YES/NO)    Files/Features (optional)
* ------------------------------------------------------------------------------
* @r-lyeh                    YES                 Initial codebase
* @zak@v4.games              YES                 N/A
* ------------------------------------------------------------------------------
*/

#ifndef V4K_H
#define V4K_H

#ifdef __cplusplus
extern "C" {
#endif

//-----------------------------------------------------------------------------
// Headers

#line 1 "v4k_config.h"
// -----------------------------------------------------------------------------
// config directives

#ifndef ENABLE_FASTCALL_LUA
#define ENABLE_FASTCALL_LUA     1 ///+
#endif

#ifndef ENABLE_PROFILER
#define ENABLE_PROFILER         ifdef(debug, 1, 0)  ///+
#endif

#ifndef ENABLE_SELFIES
#define ENABLE_SELFIES          0 ///+
#endif

#ifndef ENABLE_MEMORY_POISON
#define ENABLE_MEMORY_POISON    ifdef(debug, 1, 0) ///+
#endif

#ifndef ENABLE_MEMORY_LEAKS
#define ENABLE_MEMORY_LEAKS     0 ///+
#endif

#ifndef ENABLE_LINUX_CALLSTACKS
#define ENABLE_LINUX_CALLSTACKS 0 ///+
#endif

// -----------------------------------------------------------------------------
// if/n/def hell

#define ifdef(macro, yes, /*no*/...)   ifdef_##macro(yes, __VA_ARGS__)
#define ifndef(macro, yes, /*no*/...)  ifdef_##macro(__VA_ARGS__, yes)
#define is(macro)                      ifdef_##macro(1,0)
#define isnt(macro)                    ifdef_##macro(0,1)
#define ifdef_true(yes, /*no*/...)     yes
#define ifdef_false(yes, /*no*/...)    __VA_ARGS__

#ifdef _MSC_VER
#define ifdef_gcc                      ifdef_false
#define ifdef_mingw                    ifdef_false
#define ifdef_tcc                      ifdef_false
#define ifdef_cl                       ifdef_true
#elif defined __TINYC__
#define ifdef_gcc                      ifdef_false
#define ifdef_mingw                    ifdef_false
#define ifdef_tcc                      ifdef_true
#define ifdef_cl                       ifdef_false
#elif defined __MINGW64__ || defined __MINGW32__
#define ifdef_gcc                      ifdef_true
#define ifdef_mingw                    ifdef_true
#define ifdef_tcc                      ifdef_false
#define ifdef_cl                       ifdef_false
#else // also __clang__
#define ifdef_gcc                      ifdef_true
#define ifdef_mingw                    ifdef_false
#define ifdef_tcc                      ifdef_false
#define ifdef_cl                       ifdef_false
#endif

#ifdef __cplusplus
#define ifdef_cpp                      ifdef_true
#define ifdef_c                        ifdef_false
#else
#define ifdef_c                        ifdef_true
#define ifdef_cpp                      ifdef_false
#endif

#if defined _WIN32
#define ifdef_win32                    ifdef_true
#define ifdef_linux                    ifdef_false
#define ifdef_osx                      ifdef_false
#define ifdef_bsd                      ifdef_false
#define ifdef_ems                      ifdef_false
#elif defined __linux__
#define ifdef_win32                    ifdef_false
#define ifdef_linux                    ifdef_true
#define ifdef_osx                      ifdef_false
#define ifdef_bsd                      ifdef_false
#define ifdef_ems                      ifdef_false
#elif defined __APPLE__
#define ifdef_win32                    ifdef_false
#define ifdef_linux                    ifdef_false
#define ifdef_osx                      ifdef_true
#define ifdef_bsd                      ifdef_false
#define ifdef_ems                      ifdef_false
#elif defined __EMSCRIPTEN__
#define ifdef_win32                    ifdef_false
#define ifdef_linux                    ifdef_false
#define ifdef_osx                      ifdef_false
#define ifdef_bsd                      ifdef_false
#define ifdef_ems                      ifdef_true
#else // __FreeBSD__ || @todo: __ANDROID_API__
#define ifdef_win32                    ifdef_false
#define ifdef_linux                    ifdef_false
#define ifdef_osx                      ifdef_false
#define ifdef_bsd                      ifdef_true
#define ifdef_ems                      ifdef_false
#endif

#ifdef NDEBUG // rely on NDEBUG as the official/portable way to disable asserts
#define ifdef_debug                    ifdef_false
#define ifdef_release                  ifdef_true
#else
#define ifdef_debug                    ifdef_true
#define ifdef_release                  ifdef_false
#endif

#include <stdint.h>
#if (defined INTPTR_MAX && INTPTR_MAX == INT64_MAX) || defined(_M_X64) || defined(__amd64__) || defined(__x86_64__) || defined(__ppc64__) || __WORDSIZE == 64
#define ifdef_64                       ifdef_true
#define ifdef_32                       ifdef_false
#else
#define ifdef_64                       ifdef_false
#define ifdef_32                       ifdef_true
#endif

// -----------------------------------------------------------------------------
// new C keywords
// @todo: autorun (needed?)

#define countof(x)       (int)(sizeof (x) / sizeof 0[x])

#define concat(a,b)      conc4t(a,b)
#define conc4t(a,b)      a##b

#define macro(name)      concat(name, __LINE__)
#define defer(begin,end) for(int macro(i) = ((begin), 0); !macro(i); macro(i) = ((end), 1))
#define scope(end)       defer((void)0, end)
#define benchmark        for(double macro(t) = -time_ss(); macro(t) < 0; printf("%.2fs (" FILELINE ")\n", macro(t)+=time_ss()))
#define do_once          static int macro(once) = 0; for(;!macro(once);macro(once)=1)

#if is(cl)
#define __thread         __declspec(thread)
#elif is(tcc) && is(win32)
#define __thread         __declspec(thread) // compiles fine, but does not work apparently
#elif is(tcc)
#define __thread
#endif

// usage: bool static(audio_is_init) = audio_init();
//#define static(var)    static var; do_once var

//-----------------------------------------------------------------------------
// new C macros

#define ASSERT(expr, ...)          do { int fool_msvc[] = {0,}; if(!(expr)) { fool_msvc[0]++; breakpoint(va("!Expression failed: " #expr " " FILELINE "\n" __VA_ARGS__)); } } while(0)
#define ASSERT_ONCE(expr, ...)     do { int fool_msvc[] = {0,}; if(!(expr)) { fool_msvc[0]++; static int seen = 0; if(!seen) seen = 1, breakpoint(va("!Expression failed: " #expr " " FILELINE "\n" __VA_ARGS__)); } } while(0)
#define STATIC_ASSERT(EXPR)        typedef struct { unsigned macro(static_assert_on_line_) : !!(EXPR); } macro(static_assert_on_line_)

#define FILELINE                   __FILE__ ":" STRINGIZE(__LINE__)
#define STRINGIZE(x)               STRINGIZ3(x)
#define STRINGIZ3(x)               #x

#define EXPAND(name, ...)          EXPAND_QUOTE(EXPAND_JOIN(name, EXPAND_COUNT_ARGS(__VA_ARGS__)), (__VA_ARGS__))
#define EXPAND_QUOTE(x, y)         x y
#define EXPAND_JOIN(name, count)   EXPAND_J0IN(name, count)
#define EXPAND_J0IN(name, count)   EXPAND_J01N(name, count)
#define EXPAND_J01N(name, count)   name##count
#define EXPAND_COUNT_ARGS(...)     EXPAND_ARGS((__VA_ARGS__, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0))
#define EXPAND_ARGS(args)          EXPAND_RETURN_COUNT args
#define EXPAND_RETURN_COUNT(_1_, _2_, _3_, _4_, _5_, _6_, _7_, _8_, _9_, count, ...) count

#if is(cl) && !is(cpp)
#define INLINE __inline
#else
#define INLINE inline
#endif

#if is(cl)
#define FORCE_INLINE __forceinline
#elif is(gcc)
#define FORCE_INLINE __attribute__((always_inline)) inline
#else
#define FORCE_INLINE INLINE
#endif

#if is(cl) && (_MSC_VER <= 1700)
#define FINITE _finite
#else
#define FINITE isfinite
#endif

// usage: #define vec2(...) C_CAST(vec2, __VA_ARGS__)
// typedef union vec2 { float X,Y; }; vec2 a = {0,1}, b = vec2(0,1);
#if is(cpp)
#define C_CAST(type, ...)  ( type { __VA_ARGS__ } )
#else
#define C_CAST(type, ...)  ((type){ __VA_ARGS__ } )
#endif

// -----------------------------------------------------------------------------
// visibility

// win32 users would need to -DAPI=IMPORT/EXPORT as needed when using/building V4K as DLL.

#if is(win32)
#define IMPORT ifdef(gcc, __attribute__ ((dllimport)), __declspec(dllimport))
#define EXPORT ifdef(gcc, __attribute__ ((dllexport)), __declspec(dllexport))
#define STATIC
#else
#define IMPORT    
#define EXPORT    
#define STATIC
#endif

#ifndef API
#define API STATIC
#endif

// -----------------------------------------------------------------------------
// system headers

#ifndef _GNU_SOURCE
#define _GNU_SOURCE   // for linux
#endif

#if is(cl) && is(win32) // for VC IDE
#define _CRT_SECURE_NO_WARNINGS
#define _CRT_NONSTDC_NO_DEPRECATE
#define _WINSOCK_DEPRECATED_NO_WARNINGS
#define _WIN32_WINNT 0x0600 // 0x0502 // GetInfoAddrW/FreeAddrInfoW for X86
#endif

#if is(cl)
#include <omp.h>      // compile with /openmp to speed up some computations
#endif
#include <assert.h>
//#include <float.h>
//#include <limits.h>
#include <math.h>     // NAN
#include <stdarg.h>   // va_*(), ...
#include <stdbool.h>  // bool,true,false
#include <stdint.h>   // u/int8/16/32/64_t
#include <stdio.h>    // FILE,NULL
#include <stdlib.h>   // malloc,free,exit,
#include <string.h>   // strlen,memset,memcpy,

#if is(tcc) && is(win32) && defined(__x86_64)
#include <tgmath.h>

// @fixme workarounds on `tcc0.9.27 -m64` (win) for fmod()/trunc() functions. test: 00-easing broken otherwise
//#define trunc(x) ((double)(int64_t)(x))
//#define fmod(x,y) ((x) - trunc((x) / (y)) * (y))

// @fixme workarounds on `tcc0.9.27 -m64` (win) for all functions with ending bool argument. test: 00-anims crashes otherwise
#undef  bool
typedef char bool;

// missing libm symbols on tinycc HEAD repo (tcc-x64 pre-0.9.28)
//#define fabsf fabs
#define sqrtf sqrt
#define sinf sin
#define asinf asin
#define cosf cos
#define acosf acos
#define tanf tan
#define atan2f atan2
#define powf pow
#define floorf floor
#define logf log
#define ceilf ceil
#define copysignf copysign
//#define ldexpf ldexp
#define expf exp
//#define frexpf frexp
#define fmodf fmod
#define log10f log10
//#define logf log
#define hypotf hypot

#endif

// -----------------------------------------------------------------------------
// pragma libs

#if is(win32) && (is(cl) || is(tcc))
#pragma comment(lib, "advapi32")
#pragma comment(lib, "comdlg32")
#pragma comment(lib, "dbghelp")
#pragma comment(lib, "gdi32")
#pragma comment(lib, "ole32")
#pragma comment(lib, "shell32")
#pragma comment(lib, "user32")
#pragma comment(lib, "winmm")
#pragma comment(lib, "ws2_32")
#endif

#if is(linux) && is(tcc)
#pragma comment(lib, "dl")
#pragma comment(lib, "m")
#pragma comment(lib, "pthread")
#endif
#line 0

#line 1 "v4k_ds.h"
// data structures and utils: array, set, map, hash, sort.
// - rlyeh, public domain

// -----------------------------------------------------------------------------
// sort

API int sort_64(const void *a, const void *b);

// -----------------------------------------------------------------------------
// less

API int less_64(uint64_t a, uint64_t b);
API int less_int(int a, int b);
API int less_ptr(void *a, void *b);
API int less_str(char *a, char *b);

// -----------------------------------------------------------------------------
// un/hash

API uint32_t unhash_32(uint32_t x);
API uint32_t hash_32(uint32_t x);
API uint64_t hash_64(uint64_t x);
API uint64_t hash_flt(double x);
API uint64_t hash_str(const char* str);
API uint64_t hash_int(int key);
API uint64_t hash_ptr(const void* ptr);

// -----------------------------------------------------------------------------
// bits

API uint64_t popcnt64(uint64_t x);

// -----------------------------------------------------------------------------
// vector based allocator (x1.75 enlarge factor)

API void* vrealloc( void* p, size_t sz );
API size_t vlen( void* p );

// -----------------------------------------------------------------------------
// arrays

#if is(cpp)
#define array_cast(x) (decltype x)
#else
#define array_cast(x) (void *)
#endif

#define array(t) t*
#define array_init(t) ( (t) = 0 )
#define array_resize(t, n) ( array_c_ = array_count(t), array_n_ = (n), array_realloc_((t),array_n_), (array_n_>array_c_? memset(array_c_+(t),0,(array_n_-array_c_)*sizeof(0[t])) : (void*)0), (t) )
#define array_push(t, ...) ( array_realloc_((t),array_count(t)+1), (t)[ array_count(t) - 1 ] = (__VA_ARGS__) )
#define array_pop(t) ( array_realloc_((t), array_count(t)-1) )
#define array_back(t) ( &(t)[ array_count(t)-1 ] ) // ( (t) ? &(t)[ array_count(t)-1 ] : NULL )
#define array_data(t) (t)
#define array_at(t,i) (t[i])
#define array_count(t) (int)( (t) ? array_vlen_(t) / sizeof(0[t]) : 0u )
#define array_bytes(t) (int)( (t) ? array_vlen_(t) : 0u )
#define array_sort(t, cmpfunc) qsort( t, array_count(t), sizeof(0[t]), (uintptr_t)cmpfunc == (uintptr_t)strcmp ? (void*)strcmp_qsort : (void*)cmpfunc )
#define array_empty(t) ( !array_count(t) )

#define array_push_front(arr,x) \
    (array_resize((arr), array_count(arr)+1), memmove((arr)+1, (arr), sizeof(0[arr])*array_count(arr)), 0[arr] = (x))
#define array_pop_front(arr) ( \
    (array_count(arr) > 1 ? memmove((arr), (arr)+1, sizeof(0[arr])*(array_count(arr)-1)) : (void*)0), \
    (array_count(arr) > 0 ? array_resize(arr, array_count(arr) - 1 ) : array_resize( arr, 0 ) ) )

static __thread unsigned array_c_;
static __thread unsigned array_n_;

#if 0 // original: no reserve support
#define array_reserve(t, n) ((void)0) // not implemented
#define array_clear(t) ( array_realloc_((t), 0), (t) = 0 )
#define array_vlen_(t)  ( vlen(t) - 0 )
#define array_realloc_(t,n)  ( (t) = array_cast(t) vrealloc((t), ((n)+0) * sizeof(0[t])) )
#define array_free(t) array_clear(t)
#else // new: with reserve support (bugs?)
#define array_reserve(t, n) ( array_realloc_((t),(n)), array_clear(t) )
#define array_clear(t) ( array_realloc_((t),0) ) // -1
#define array_vlen_(t)  ( vlen(t) - sizeof(0[t]) ) // -1
#define array_realloc_(t,n)  ( (t) = array_cast(t) vrealloc((t), ((n)+1) * sizeof(0[t])) ) // +1
#define array_free(t) ( array_realloc_((t), -1), (t) = 0 ) // -1
#endif

#define array_reverse(t) \
    do if( array_count(t) ) { \
        for(int l = array_count(t), e = l-1, i = (array_push(t, 0[t]), 0); i <= e/2; ++i ) \
            { l[t] = i[t]; i[t] = (e-i)[t]; (e-i)[t] = l[t]; } \
        array_pop(t); \
    } while(0)

#define array_foreach(t,val_t,v) for each_array(t,val_t,v)
#define each_array(t,val_t,v) \
    ( int __it = 0, __end = array_count(t); __it < __end; ++__it ) \
        for( val_t v = __it[t], *on__ = &v; on__; on__ = 0 )

#define array_foreach_ptr(t,val_t,v) for each_array_ptr(t,val_t,v)
#define each_array_ptr(t,val_t,v) \
    ( int __it = 0, __end = array_count(t); __it < __end; ++__it ) \
        for( val_t *v = (val_t*)&__it[t]; v; v = 0 )

#define array_search(t, key, cmpfn) /* requires sorted array beforehand */ \
    bsearch(&key, t, array_count(t), sizeof(t[0]), cmpfn )

#define array_insert(t, i, n) do { \
    int ac = array_count(t); \
    if( i >= ac ) { \
        array_push(t, n); \
    } else { \
        array_push(t, array_back(t)); \
        memmove( &(t)[(i)+1], &(t)[i], (ac - (i)) * sizeof(t[0]) ); \
        (t)[ i ] = (n); \
    } \
} while(0)

#define array_copy(t, src) do { /*todo: review old vrealloc call!*/ \
    array_free(t); \
    (t) = vrealloc( (t), array_count(src) * sizeof(0[t])); \
    memcpy( (t), src, array_count(src) * sizeof(0[t])); \
} while(0)

#define array_erase(t, i) do { /*may alter ordering*/ \
    memcpy( &(t)[i], &(t)[array_count(t) - 1], sizeof(0[t])); \
    array_pop(t); \
} while(0)

#define array_unique(t, cmpfunc) do { /*@todo: optimize me. requires array_sort() beforehand*/ \
    int cnt = array_count(t), cnt_bak = cnt; \
     if( cnt > 1 ) { \
        for( int i = 1; i < cnt; ++i ) { \
            while( i < cnt && !cmpfunc(&(t)[i-1], &(t)[i]) ) { \
                memmove(&(t)[i-1], &(t)[i], (cnt - 1 - i) * sizeof((t)[0]) ) ; \
                --cnt; \
            } \
         } \
        if( cnt_bak != cnt ) array_resize((t), cnt); \
     } \
 } while(0)

#if 0 // snippet below does work
#define array_unique(t, cmpfunc) \
    array_sort(t, cmpfunc); \
    for( int i = 0, end = array_count(t) - 1; i < end; ) { \
        if( !strcmp(t[i], t[i+1]) ) { \
            /* array_erase(t, i+1); */ \
            memmove(&(t)[i+1], &(t)[i+2], (end - 1 - i) * sizeof((t)[0]) ); \
            array_pop(t); \
            --end; \
        } else { \
            ++i; \
        } \
    }
#endif

#define array_shuffle(t) do { /* https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle */ \
    void* tmp = stack(sizeof(0[t])); \
    for( int i = 0, n = array_count(t); i < n; ++i ) { \
        int j = randi(i, n); /* j random integer such that [i,n) i<=j<n */ \
        memcpy(tmp, &j[t], sizeof(0[t])); \
        memcpy(&j[t], &i[t], sizeof(0[t])); \
        memcpy(&i[t], tmp, sizeof(0[t])); \
    } \
} while(0)

// -----------------------------------------------------------------------------
// set<K>
// ideas from: https://en.wikipedia.org/wiki/Hash_table
// ideas from: https://probablydance.com/2017/02/26/i-wrote-the-fastest-hashtable/
// ideas from: http://www.idryman.org/blog/2017/05/03/writing-a-damn-fast-hash-table-with-tiny-memory-footprints/

// config
#ifndef SET_HASHSIZE
#define SET_HASHSIZE (4096 << 4)
#endif
#ifndef SET_DONT_ERASE
#define SET_DONT_ERASE 1
#endif

// public api
#define set(K) \
    struct { set base; struct { set_item p; K key; } tmp, *ptr; K *tmpval; \
        int (*typed_cmp)(K, K); uint64_t (*typed_hash)(K); } *

#define set_init(m, cmpfn, hashfn) ( \
    (m) = set_cast(m) REALLOC(0, sizeof(*m)), \
    set_init(&(m)->base), \
    (m)->base.cmp = (int(*)(void*,void*))( (m)->typed_cmp = set_cast(cmpfn) cmpfn ), \
    (m)->base.hash = (uint64_t(*)(void*))( (m)->typed_hash = set_cast(hashfn) hashfn ) \
    )

#define set_free(m) ( \
    set_clear(m), \
    set_free(&(m)->base), \
    (m) = set_cast(m) REALLOC((m), 0), \
    (m) = 0 \
    )

#define set_insert(m, k) ( \
    (m)->ptr = set_cast((m)->ptr) REALLOC(0, sizeof((m)->tmp)), \
    (m)->ptr->p.keyhash = (m)->typed_hash((m)->ptr->key = (k)), \
    set_insert(&(m)->base, &(m)->ptr->p, &(m)->ptr->key, (m)->ptr->p.keyhash, (m)->ptr), \
    &(m)->ptr->key \
    )

#define set_find(m, k) ( \
    (m)->ptr = &(m)->tmp, \
    (m)->ptr->p.keyhash = (m)->typed_hash((m)->ptr->key = (k)), \
    (m)->ptr = set_cast((m)->ptr) set_find(&(m)->base, &(m)->ptr->key, (m)->ptr->p.keyhash), \
    (m)->ptr ? &(m)->ptr->key : 0 \
    )

#define set_find_or_add(m, k) ( \
    (m)->tmp.key = (k), \
    (m)->tmpval = set_find((m), ((m)->tmp.key)), \
    (m)->tmpval = (m)->tmpval ? (m)->tmpval : set_insert((m), ((m)->tmp.key)) \
    )

#define set_find_or_add_allocated_key(m, k) ( \
    (m)->tmp.key = (k), \
    (m)->tmpval = set_find((m), ((m)->tmp.key)), \
    (m)->tmpval = (m)->tmpval ? FREE((m)->tmp.key), (m)->tmpval : set_insert((m), ((m)->tmp.key)) \
    )

#define set_erase(m, k) ( \
    (m)->ptr = &(m)->tmp, \
    (m)->ptr->p.keyhash = (m)->typed_hash((m)->ptr->key = (k)), \
    set_erase(&(m)->base, &(m)->ptr->key, (m)->ptr->p.keyhash) \
    )

#define set_foreach for each_set
#define each_set(m,key_t,k) \
    ( int i_ = (m)->base.count ? 0 : SET_HASHSIZE; i_ < SET_HASHSIZE; ++i_) \
        for( set_item *cur_ = (m)->base.array[i_], *on_ = cur_; cur_; on_ = cur_ = cur_->next ) \
            for( key_t k = *(key_t *)cur_->key; on_; on_ = 0 )

#define set_foreach_ptr for each_set_ptr
#define each_set_ptr(m,key_t,k) \
    ( int i_ = (m)->base.count ? 0 : SET_HASHSIZE; i_ < SET_HASHSIZE; ++i_) \
        for( set_item *cur_ = (m)->base.array[i_], *on_ = cur_; cur_; on_ = cur_ = cur_->next ) \
            for( key_t *k = (key_t *)cur_->key; on_; on_ = 0 )

#define set_clear(m) ( \
    set_clear(&(m)->base) \
    )

#define set_count(m)        set_count(&(m)->base)
#define set_gc(m)           set_gc(&(m)->base)

#ifndef set_init_int
#define set_init_int(m) set_init((m), less_int, hash_64) // hash_int)
#define set_init_str(m) set_init((m), less_str, hash_str)
#define set_init_ptr(m) set_init((m), less_ptr, hash_ptr)
#endif

// private:

#if is(cpp)
#define set_cast(t) (decltype(t))
#else
#define set_cast(t) (void *)
#endif

typedef struct set_item {
    struct set_item *next;

    uint64_t keyhash;
    void *key;
    void *super;
} set_item;

typedef struct set {
    array(set_item*) array;
    int (*cmp)(void *, void *);
    uint64_t (*hash)(void *);
    int count;
} set;

API void  (set_init)(set *m);
API void  (set_free)(set *m);

API void  (set_insert)(set *m, set_item *p, void *key, uint64_t keyhash, void *super);
API void  (set_erase)(set *m, void *key, uint64_t keyhash);
API void* (set_find)(const set *m, void *key, uint64_t keyhash);
API int   (set_count)(const set *m);
API void  (set_gc)(set *m); // only if using SET_DONT_ERASE
API void  (set_clear)(set* m);

// -----------------------------------------------------------------------------
// map<K,V>
// ideas from: https://en.wikipedia.org/wiki/Hash_table
// ideas from: https://probablydance.com/2017/02/26/i-wrote-the-fastest-hashtable/
// ideas from: http://www.idryman.org/blog/2017/05/03/writing-a-damn-fast-hash-table-with-tiny-memory-footprints/

// config
#ifndef MAP_HASHSIZE
#define MAP_HASHSIZE (4096 << 4)
#endif
#ifndef MAP_DONT_ERASE
#define MAP_DONT_ERASE 1
#endif

// public api
#define map(K,V) \
    struct { map base; struct { pair p; K key; V val; } tmp, *ptr; V* tmpval; \
        int (*typed_cmp)(K, K); uint64_t (*typed_hash)(K); } *

#define map_init(m, cmpfn, hashfn) ( \
    (m) = map_cast(m) REALLOC(0, sizeof(*(m))), \
    map_init(&(m)->base), \
    (m)->base.cmp = (int(*)(void*,void*))( (m)->typed_cmp = map_cast((m)->typed_cmp) cmpfn), \
    (m)->base.hash = (uint64_t(*)(void*))( (m)->typed_hash = map_cast((m)->typed_hash) hashfn ) \
    )

#define map_free(m) ( \
    map_free(&(m)->base), \
    map_cast(m) REALLOC((m), sizeof(*(m))), (m) = 0 \
    )

#define map_insert(m, k, v) ( \
    (m)->ptr = map_cast((m)->ptr) REALLOC(0, sizeof((m)->tmp)), \
    (m)->ptr->val = (v), \
    (m)->ptr->p.keyhash = (m)->typed_hash((m)->ptr->key = (k)), \
    map_insert(&(m)->base, &(m)->ptr->p, &(m)->ptr->key, &(m)->ptr->val, (m)->ptr->p.keyhash, (m)->ptr), \
    &(m)->ptr->val \
    )

#define map_find(m, k) ( \
    (m)->ptr = &(m)->tmp, \
    (m)->ptr->p.keyhash = (m)->typed_hash((m)->ptr->key = (k)), \
    (m)->ptr = map_cast((m)->ptr) map_find(&(m)->base, &(m)->ptr->key, (m)->ptr->p.keyhash), \
    (m)->ptr ? &(m)->ptr->val : 0 \
    )

#define map_find_or_add(m, k, v) ( \
    (m)->tmp.key = (k), (m)->tmp.val = (v), \
    (m)->tmpval = map_find((m), ((m)->tmp.key)), \
    (m)->tmpval = (m)->tmpval ? (m)->tmpval : map_insert((m), ((m)->tmp.key), ((m)->tmp.val)) \
    )

#define map_find_or_add_allocated_key(m, k, v) ( \
    (m)->tmp.key = (k), (m)->tmp.val = (v), \
    (m)->tmpval = map_find((m), ((m)->tmp.key)), \
    (m)->tmpval = (m)->tmpval ? FREE((m)->tmp.key), (m)->tmpval : map_insert((m), ((m)->tmp.key), ((m)->tmp.val)) \
    )

#define map_erase(m, k) ( \
    (m)->ptr = &(m)->tmp, \
    (m)->ptr->p.keyhash = (m)->typed_hash((m)->ptr->key = (k)), \
    map_erase(&(m)->base, &(m)->ptr->key, (m)->ptr->p.keyhash) \
    )

#define map_foreach for each_map
#define each_map(m,key_t,k,val_t,v) \
    ( int i_ = (m)->base.count ? 0 : MAP_HASHSIZE; i_ < MAP_HASHSIZE; ++i_) \
        for( pair *cur_ = (m)->base.array[i_], *on_ = cur_; cur_; on_ = cur_ = cur_->next ) \
            for( key_t k = *(key_t *)cur_->key; on_; ) \
                for( val_t v = *(val_t *)cur_->value; on_; on_ = 0 )

#define map_foreach_ptr for each_map_ptr
#define each_map_ptr(m,key_t,k,val_t,v) \
    ( int i_ = (m)->base.count ? 0 : MAP_HASHSIZE; i_ < MAP_HASHSIZE; ++i_) \
        for( pair *cur_ = (m)->base.array[i_], *on_ = cur_; cur_; on_ = cur_ = cur_->next ) \
            for( key_t *k = (key_t *)cur_->key; on_; ) \
                for( val_t *v = (val_t *)cur_->value; on_; on_ = 0 )

#define map_foreach_ptr_sorted for each_map_ptr_sorted
#define each_map_ptr_sorted(m,key_t,k,val_t,v) \
    ( int i_ = (map_sort(&(m)->base), 0); i_ < array_count((m)->base.sorted); ++i_) \
        for( pair *cur_ = (m)->base.sorted[i_]; cur_; ) \
            for( key_t *k = (key_t *)cur_->key; cur_; ) \
                for( val_t *v = (val_t *)cur_->value; cur_; cur_ = 0 )

#define map_clear(m) ( \
    map_clear(&(m)->base) \
    )

#define map_count(m)        map_count(&(m)->base)
#define map_gc(m)           map_gc(&(m)->base)

// aliases:

#ifndef map_init_int
#define map_init_int(m)     map_init((m), less_int, hash_64) // hash_int
#define map_init_str(m)     map_init((m), less_str, hash_str)
#define map_init_ptr(m)     map_init((m), less_ptr, hash_ptr)
#endif

// private:

#if is(cpp)
#define map_cast(t) (decltype(t))
#else
#define map_cast(t) (void *)
#endif

typedef struct pair {
    struct pair *next;

    uint64_t keyhash;
    void *key;
    void *value;
    void *super;
} pair;

typedef struct map {
    array(pair*) array;
    int (*cmp)(void *, void *);
    uint64_t (*hash)(void *);
    int count:31;

    int is_sorted:1;
    array(pair*) sorted;
} map;

API void  (map_init)(map *m);
API void  (map_free)(map *m);

API void  (map_insert)(map *m, pair *p, void *key, void *value, uint64_t keyhash, void *super);
API void  (map_erase)(map *m, void *key, uint64_t keyhash);
API void* (map_find)(map *m, void *key, uint64_t keyhash);
API int   (map_count)(map *m);
API void  (map_gc)(map *m); // only if using MAP_DONT_ERASE
API bool  (map_sort)(map* m);
API void  (map_clear)(map* m);

// -----------------------------------------------------------------------------
// four-cc, eight-cc

API unsigned cc4(const char *id);
API uint64_t cc8(const char *id);
API char *cc4str(unsigned cc);
API char *cc8str(uint64_t cc);

// fast path
#define cc4(abcd)      ( *(unsigned*) #abcd     "    "     ) // lil32() ?
#define cc8(abcdefgh)  ( *(uint64_t*) #abcdefgh "        " ) // lil64() ?
#line 0

#line 1 "v4k_math.h"
// -----------------------------------------------------------------------------
// math framework: rand, ease, vec2, vec3, vec4, quat, mat2, mat33, mat34, mat4
// - rlyeh, public domain
//
// Credits: @ands+@krig+@vurtun (PD), @datenwolf (WTFPL2), @evanw+@barerose (CC0), @sgorsten (Unlicense).

#define C_EPSILON  (1e-6)
#define C_PI       (3.141592654f) // (3.14159265358979323846f)
#define TO_RAD     (C_PI/180.f)
#define TO_DEG     (180.f/C_PI)

// ----------------------------------------------------------------------------

//#define ptr(type)         0[&(type).x]
#define vec2i(x, y     )  C_CAST(vec2i,(int)(x),   (int)(y)                          )
#define vec3i(x, y, z  )  C_CAST(vec3i,(int)(x),   (int)(y),   (int)(z)              )
#define vec2(x, y      )  C_CAST(vec2, (float)(x), (float)(y)                        )
#define vec3(x, y, z   )  C_CAST(vec3, (float)(x), (float)(y), (float)(z),           )
#define vec4(x, y, z, w)  C_CAST(vec4, (float)(x), (float)(y), (float)(z), (float)(w))
#define quat(x, y, z, w)  C_CAST(quat, (float)(x), (float)(y), (float)(z), (float)(w))
#define axis(x, y, z)     C_CAST(axis, (float)(x), (float)(y), (float)(z))
#define mat33(...)        C_CAST(mat33, __VA_ARGS__ )
#define mat34(...)        C_CAST(mat34, __VA_ARGS__ )
#define mat44(...)        C_CAST(mat44, __VA_ARGS__ )

typedef union vec2i{ struct { int X,Y; };       struct { int x,y; }; struct { int r,g; }; struct { int w,h; }; struct { int min,max; }; struct { int from,to; }; struct { int src,dst; }; int v2[2]; int array[1]; } vec2i;
typedef union vec3i{ struct { int X,Y,Z; };     struct { int x,y,z; }; struct { int r,g,b; }; struct { int w,h,d; }; struct { int min,max; }; struct { int from,to,step; }; struct { int src,dst; }; int v3[3]; int array[1]; } vec3i;
typedef union vec2 { struct { float X,Y; };     struct { float x,y; }; struct { float r,g; }; struct { float w,h; }; struct { float min,max; }; struct { float from,to; }; struct { float src,dst; }; float v2[2]; float array[1]; } vec2;
typedef union vec3 { struct { float X,Y,Z; };   struct { float x,y,z; }; struct { float r,g,b; }; struct { float min,max; }; struct { float from,to; }; vec2 xy; vec2 rg; vec2 wh; float v3[3]; float array[1]; } vec3;
typedef union vec4 { struct { float X,Y,Z,W; }; struct { float x,y,z,w; }; struct { float r,g,b,a; }; struct { float min,max; }; struct { float from,to; }; vec2 xy; vec3 xyz; vec2 rg; vec3 rgb; vec2 wh; vec3 whd; float v4[4]; float array[1]; } vec4;
typedef union quat { struct { float X,Y,Z,W; }; struct { float x,y,z,w; }; vec3 xyz; vec4 xyzw; float v4[4]; float array[1]; } quat;
typedef float mat33[9];
typedef float mat34[12];
typedef float mat44[16];

// ----------------------------------------------------------------------------

API void     randset(uint64_t state);
API uint64_t rand64(void);
API double   randf(void); // [0, 1) interval
API int      randi(int mini, int maxi); // [mini, maxi) interval
//API double rng(void); // [0..1) Lehmer RNG "minimal standard"

// ----------------------------------------------------------------------------

API float simplex1( float x );
API float simplex2( vec2 xy );
API float simplex3( vec3 xyz );
API float simplex4( vec4 xyzw );

// ----------------------------------------------------------------------------

API float ease_linear(float t);

API float ease_out_sine(float t);
API float ease_out_quad(float t);
API float ease_out_cubic(float t);
API float ease_out_quart(float t);
API float ease_out_quint(float t);
API float ease_out_expo(float t);
API float ease_out_circ(float t);
API float ease_out_back(float t);
API float ease_out_elastic(float t);
API float ease_out_bounce(float t);

API float ease_in_sine(float t);
API float ease_in_quad(float t);
API float ease_in_cubic(float t);
API float ease_in_quart(float t);
API float ease_in_quint(float t);
API float ease_in_expo(float t);
API float ease_in_circ(float t);
API float ease_in_back(float t);
API float ease_in_elastic(float t);
API float ease_in_bounce(float t);

API float ease_inout_sine(float t);
API float ease_inout_quad(float t);
API float ease_inout_cubic(float t);
API float ease_inout_quart(float t);
API float ease_inout_quint(float t);
API float ease_inout_expo(float t);
API float ease_inout_circ(float t);
API float ease_inout_back(float t);
API float ease_inout_elastic(float t);
API float ease_inout_bounce(float t);

API float ease_inout_perlin(float t);

enum EASE_FLAGS {
    EASE_LINEAR,
    EASE_SINE,
    EASE_QUAD,
    EASE_CUBIC,
    EASE_QUART,
    EASE_QUINT,
    EASE_EXPO,
    EASE_CIRC,
    EASE_BACK,
    EASE_ELASTIC,
    EASE_BOUNCE,

    EASE_IN,
    EASE_INOUT = EASE_IN * 2,
    EASE_OUT = 0,
};

API float ease(float t01, unsigned mode); // 0=linear,1=out_sine...31=inout_perlin

API float ease_ping_pong(float t, float(*fn1)(float), float(*fn2)(float));
API float ease_pong_ping(float t, float(*fn1)(float), float(*fn2)(float));

// ----------------------------------------------------------------------------

API float deg      (float radians);
API float rad      (float degrees);

API int   mini     (int    a, int    b);
API int   maxi     (int    a, int    b);
API int   absi     (int    a          );
API int   clampi   (int v,int a,int b);

API float minf     (float  a, float  b);
API float maxf     (float  a, float  b);
API float absf     (float  a          );
API float pmodf    (float  a, float  b);
API float signf    (float  a)           ;
API float clampf   (float v,float a,float b);
API float mixf     (float a,float b,float t);
API float fractf   (float a);

// ----------------------------------------------------------------------------

API vec2  ptr2     (const float *a    );
//
API vec2  neg2     (vec2   a          );
API vec2  add2     (vec2   a, vec2   b);
API vec2  sub2     (vec2   a, vec2   b);
API vec2  mul2     (vec2   a, vec2   b);
API vec2  div2     (vec2   a, vec2   b);
API vec2  inc2     (vec2   a, float  b);
API vec2  dec2     (vec2   a, float  b);
API vec2  scale2   (vec2   a, float  b);
API vec2  pmod2    (vec2   a, float  b);
API vec2  min2     (vec2   a, vec2   b);
API vec2  max2     (vec2   a, vec2   b);
API vec2  abs2     (vec2   a          );
API vec2  floor2   (vec2   a          );
API vec2  fract2   (vec2   a          );
API vec2  ceil2    (vec2   a          );
API float dot2     (vec2   a, vec2   b);
API vec2  refl2    (vec2   a, vec2   b);
API float cross2   (vec2   a, vec2   b);
API float len2sq   (vec2   a          );
API float len2     (vec2   a          );
API vec2  norm2    (vec2   a          );
API int   finite2  (vec2   a          );
API vec2  mix2  (vec2 a,vec2 b,float t);
API vec2  clamp2(vec2 v,float a,float b);
// ----------------------------------------------------------------------------

API vec3  rnd3     (void); // @todo: rnd2,rnd4,rndq
API vec3  ptr3     (const float *a    );
API vec3  vec23    (vec2   a, float z );
//
API vec3  neg3     (vec3   a          );
API vec3  add3     (vec3   a, vec3   b);
API vec3  sub3     (vec3   a, vec3   b);
API vec3  mul3     (vec3   a, vec3   b);
API vec3  div3     (vec3   a, vec3   b);
API vec3  inc3     (vec3   a, float  b);
API vec3  dec3     (vec3   a, float  b);
API vec3  scale3   (vec3   a, float  b);
API vec3  pmod3    (vec3   a, float  b);
API vec3  min3     (vec3   a, vec3   b);
API vec3  max3     (vec3   a, vec3   b);
API vec3  abs3     (vec3   a          );
API vec3  floor3   (vec3   a          );
API vec3  fract3   (vec3   a          );
API vec3  ceil3    (vec3   a          );
API vec3  cross3   (vec3   a, vec3   b);
API float dot3     (vec3   a, vec3   b);
API vec3  refl3    (vec3   a, vec3   b);
API float len3sq   (vec3   a          );
API float len3     (vec3   a          );
API vec3  norm3    (vec3   a          );
API vec3  norm3sq  (vec3   a          );
API int   finite3  (vec3   a          );
API vec3  mix3  (vec3 a,vec3 b,float t);
API vec3  clamp3(vec3 v,float a,float b);
//vec3 tricross3 (vec3 a, vec3 b, vec3 c);
API void  ortho3   (vec3 *left, vec3 *up, vec3 v);

API vec3  rotatex3 (vec3 dir, float degrees);
API vec3  rotatey3 (vec3 dir, float degrees);
API vec3  rotatez3 (vec3 dir, float degrees);

// ----------------------------------------------------------------------------

API vec4  ptr4     (const float *a    );
API vec4  vec34    (vec3   a, float w );
//
API vec4  neg4     (vec4   a          );
API vec4  add4     (vec4   a, vec4   b);
API vec4  sub4     (vec4   a, vec4   b);
API vec4  mul4     (vec4   a, vec4   b);
API vec4  div4     (vec4   a, vec4   b);
API vec4  inc4     (vec4   a, float  b);
API vec4  dec4     (vec4   a, float  b);
API vec4  scale4   (vec4   a, float  b);
API vec4  pmod4    (vec4   a, float  b);
API vec4  min4     (vec4   a, vec4   b);
API vec4  max4     (vec4   a, vec4   b);
API vec4  abs4     (vec4   a          );
API vec4  floor4   (vec4   a          );
API vec4  fract4   (vec4   a          );
API vec4  ceil4    (vec4   a          );
API float dot4     (vec4   a, vec4   b);
API vec4  refl4    (vec4   a, vec4   b);
API float len4sq   (vec4   a          );
API float len4     (vec4   a          );
API vec4  norm4    (vec4   a          );
API vec4  norm4sq  (vec4   a          );
API int   finite4  (vec4   a          );
API vec4  mix4  (vec4 a,vec4 b,float t);
API vec4  clamp4(vec4 v,float a,float b);
// vec4 cross4(vec4 v0, vec4 v1);

// ----------------------------------------------------------------------------

API quat  idq      (                  );
API quat  ptrq     (const float *a    );
API quat  vec3q    (vec3   a, float w );
API quat  vec4q    (vec4   a          );
//
API quat  negq     (quat   a          );
API quat  conjq    (quat   a          );
API quat  addq     (quat   a, quat   b);
API quat  subq     (quat   a, quat   b);
API quat  mulq     (quat   p, quat   q);
API quat  scaleq   (quat   a, float  s);
API quat  normq    (quat   a          );
API float dotq     (quat   a, quat   b);
API quat  mixq(quat a, quat b, float t);
/* quat lerpq(quat a, quat b, float s);
    return norm(quat((1-s)*a.x + s*b.x, (1-s)*a.y + s*b.y, (1-s)*a.z + s*b.z, (1-s)*a.w + s*b.w));
}*/
API quat slerpq(quat a, quat b, float s);

API quat  rotationq(float deg,float x,float y,float z);
API quat  mat44q   (mat44 M);

API vec3 rotate3q_2(vec3 v, quat q);
API vec3 rotate3q(vec3 v, quat r);

// euler <-> quat
API vec3  euler    (quat q);
API quat  eulerq   (vec3 pyr_degrees);

// ----------------------------------------------------------------------------

API void scaling33(mat33 m, float x, float y, float z);
API void scale33(mat33 m, float x, float y, float z);
API void id33(mat33 m);
API void extract33(mat33 m, const mat44 m4);
API void copy33(mat33 m, const mat33 a);//
API vec3 mulv33(mat33 m, vec3 v);
API void multiply33x2(mat33 m, const mat33 a, const mat33 b);

API void rotation33(mat33 m, float degrees, float x,float y,float z);
API void rotationq33(mat33 m, quat q);
API void rotate33(mat33 r, float degrees, float x,float y,float z);
API void compose33(mat33 m, quat r, vec3 s);

// ----------------------------------------------------------------------------

API void id34(mat34 m);
API void copy34(mat34 m, const mat34 a);
API void scale34(mat34 m, float s);
API void add34(mat34 m, mat34 n);
API void muladd34(mat34 m, mat34 n, float s);
API void add34x2(mat34 m, mat34 n, mat34 o);
API void lerp34(mat34 m, mat34 n, mat34 o, float alpha); // mix34?
API void multiply34x2(mat34 m, const mat34 m0, const mat34 m1);
API void multiply34(mat34 m, const mat34 a);
API void multiply34x3(mat34 m, const mat34 a, const mat34 b, const mat34 c);
API void compose34(mat34 m, vec3 t, quat q, vec3 s);
API void invert34(mat34 m, const mat34 o);

// ----------------------------------------------------------------------------

API void id44(mat44 m);
API void identity44(mat44 m);
API void copy44(mat44 m, const mat44 a);
API void multiply44x2(mat44 m, const mat44 a, const mat44 b);
API void multiply44x3(mat44 m, const mat44 a, const mat44 b, const mat44 c);
API void multiply44(mat44 m, const mat44 a);
// ---
API void ortho44(mat44 m, float l, float r, float b, float t, float n, float f);
API void frustum44(mat44 m, float l, float r, float b, float t, float n, float f);
API void perspective44(mat44 m, float fovy_degrees, float aspect, float nearp, float farp);
API void lookat44(mat44 m, vec3 eye, vec3 center, vec3 up);
// ---
API void translation44(mat44 m, float x, float y, float z);
API void translate44(mat44 m, float x, float y, float z);
API void relocate44(mat44 m, float x, float y, float z);
API void rotationq44(mat44 m, quat q);
API void rotation44(mat44 m, float degrees, float x, float y, float z);
API void rotate44(mat44 m, float degrees, float x, float y, float z);
API void scaling44(mat44 m, float x, float y, float z);
API void scale44(mat44 m, float x, float y, float z);
// ---
API void transpose44(mat44 m, const mat44 a);
API float det44(const mat44 M);
API bool invert44(mat44 T, const mat44 M);

API void compose44(mat44 m, vec3 t, quat q, vec3 s);

// ----------------------------------------------------------------------------

API vec3 transformq(const quat q, const vec3 v);
API vec3 transform33(const mat33 m, vec3 p);
API vec3 transform344(const mat44 m, const vec3 p);
API vec4 transform444(const mat44 m, const vec4 p);
API bool unproject44(vec3 *out, vec3 xyd, vec4 viewport, mat44 mvp);

// ----------------------------------------------------------------------------
// !!! for debugging

API void print2( vec2 v );
API void print3( vec3 v );
API void print4( vec4 v );
API void printq( quat q );
API void print33( float *m );
API void print34( float *m );
API void print44( float *m );
#line 0


#line 1 "v4k_ai.h"
typedef enum SWARM_DISTANCE {
    SWARM_DISTANCE_LINEAR,
    SWARM_DISTANCE_INVERSE_LINEAR,
    SWARM_DISTANCE_QUADRATIC,
    SWARM_DISTANCE_INVERSE_QUADRATIC
} SWARM_DISTANCE;

#define boid(...) C_CAST(boid_t, __VA_ARGS__)

typedef struct boid_t {
    vec3 position;
    vec3 velocity;
    vec3 acceleration;
    vec3 prev_position;
} boid_t;

typedef struct swarm_t {
    array(boid_t) boids;

    float perception_radius; // determines the vision radius of each boid. Only boids within this distance influence each other.

    float separation_weight; // how much boids repel each other
    SWARM_DISTANCE separation_type;

    float alignment_weight; // how much boids want go in the same direction
    float cohesion_weight; // how much boids want to be in the center of the swarm

    float steering_weight;
    array(vec3) steering_targets;
    SWARM_DISTANCE steering_target_type;

    float blindspot_angledeg;
    float max_acceleration; // how fast each boid can change its direction
    float max_velocity; // how fast each boid can move

    // private:
    map(vec3*, array(boid_t*)) voxel_cache_;
    float blindspot_angledeg_compare_value_;
} swarm_t;

API swarm_t swarm();
API void    swarm_update(swarm_t *self, float delta); // acc,vel,pos
API void    swarm_update_acceleration_only(swarm_t *self); // acc
API void    swarm_update_acceleration_and_velocity_only(swarm_t *self, float delta); // acc,vel

API int     ui_swarm(swarm_t *self);

// pathfinding -----------------------------------------------------------------

API int pathfind_astar(int width, int height, const unsigned* map, vec2i src, vec2i dst, vec2i* path, size_t maxpath);
#line 0

#line 1 "v4k_bt.h"
// Behavior trees: decision planning and decision making.
// Supersedes finite state-machines (FSM) and hierarchical finite state-machines (HFSM).
// - rlyeh, public domain.
//
// [ref] https://outforafight.wordpress.com/2014/07/15/behaviour-behavior-trees-for-ai-dudes-part-1/
// [ref] https://www.gameaipro.com/GameAIPro/GameAIPro_Chapter06_The_Behavior_Tree_Starter_Kit.pdf
// [ref] https://gitlab.com/NotYetGames/DlgSystem/-/wikis/Dialogue-Manual
// [ref] https://towardsdatascience.com/designing-ai-agents-behaviors-with-behavior-trees-b28aa1c3cf8a
// [ref] https://docs.nvidia.com/isaac/packages/behavior_tree/doc/behavior_trees.html
// [ref] https://docs.unrealengine.com/4.26/en-US/InteractiveExperiences/ArtificialIntelligence/BehaviorTrees/
// [ref] gdc ChampandardDaweHernandezCerpa_BehaviorTrees.pdf @todo debugging
// [ref] https://docs.cocos.com/cocos2d-x/manual/en/actions/

#if 0

The nodes in a behavior tree can be broadly categorized into three main types: control nodes, task nodes, and decorator nodes. Here is a brief description of each category:

Control Nodes: Control nodes are used to control the flow of the behavior tree. They determine the order in which child nodes are executed and how the results of those nodes are combined. They are usually parent nodes.
Action Nodes: Action nodes are used to perform specific actions or tasks within the behavior tree. They can include actions such as moving, attacking, or interacting with objects in the game world. They are usually leaf nodes.
Decorator Nodes: Decorator nodes are used to modify the behavior of child nodes in some way. They can be used to repeat child nodes, invert the result of a child node, or add a cooldown period between executions. They are usually located between control and action nodes.

--- VARIABLES

Key Prefixes:
    {visiblity:(l)ocal,s(q)uad,(r)ace,(f)action,(g)lobal}
    [persistence:(t)emp,(u)serdata,(s)avegame,(c)loud] + '_' + name.
    [persistence:(tmp),(usr)data,(sav)egame,(net)cloud] + '_' + name.

Ie, l_health = 123.4, gsav_player = "john"

--- ACTION NODES

[ ] * Actions/Behaviors have a common structure:
[ ]     - Entry point (function name) for a C call or Lua script.
[ ] * Status:
[ ]     - Uninitialized (never run)
[ ]     - Running (in progress)
[ ]     - Suspended (on hold till resumed)
[ ]     - Success (finished and succeeded)
[ ]     - Failure (finished and failed)
[ ] * Optional callbacks:
[ ]     - on_enter
[ ]     - on_leave
[ ]     - on_success
[ ]     - on_failure
[ ]     - on_suspend
[ ]     - on_resume

[x] Action Node: This node performs a single action, such as moving to a specific location or attacking a target.
[ ] Blackboard Node: Node that reads and writes data to a shared memory space known as a blackboard. The blackboard can be used to store information that is relevant to multiple nodes in the behavior tree.
[ ]     SetKey(keyVar,object)
[ ]     HasKey(keyVar)
[ ]     CompareKeys(keyVar1, operator < <= > >= == !=, keyVar2)
[ ]     SetTags(names=blank,cooldownTime=inf,bIsCooldownAdditive=false)
[ ]     HasTags(names=blank,bAllRequired=true)
[ ]     PushToStack(keyVar,itemObj): creates a new stack if one doesn<EFBFBD>t exist, and stores it in the passed variable name, and then pushes <EFBFBD>item<EFBFBD> object onto it.
[ ]     PopFromStack(keyVar,itemVar): pop pops an item off the stack, and stores it in the itemVar variable, failing if the stack is already empty.
[ ]     IsEmptyStack(keyVar): checks if the stack passed is empty and returns success if it is, and failure if its not.
[ ] Communication Node: This is a type of action node that allows an AI agent to communicate with other agents or entities in the game world. The node takes an input specifying the message to be communicated and the recipient(s) of the message (wildmask,l/p/f/g prefixes). The node then sends the message to the designated recipient(s) and returns success when the communication is completed. This node can be useful for implementing behaviors that require the AI agent to coordinate with other agents or to convey information to the player. It could use a radius argument to specify the maximum allowed distance for the recipients.
[ ] Condition Node: A leaf node that checks a specific condition, such as the distance to an object, the presence of an enemy, or the status of a health bar.
[ ]     Distance Condition Node: This is a type of condition node that evaluates whether an AI agent is within a specified distance of a target object or location. The node takes two inputs: the current position of the AI agent and the position of the target object or location. If the distance between the two is within a specified range, the node returns success. If the distance is outside of the specified range, the node returns failure. This node can be useful for implementing behaviors that require the AI agent to maintain a certain distance from a target, such as following or avoiding an object. Could use a flag to disambiguate between linear distance and path distance.
[ ]     Query Node: This node checks a condition and returns success or failure based on the result. For example, a query node could check whether an enemy is within range or whether a door is locked.
[ ]         Query Node: A type of decorator node that retrieves information from a database or external system, such as a web service or file system. The Query node can be used to retrieve data that is not available within the game engine, such as weather or traffic conditions.
[ ]     A condition is made of:
[ ]     - Optional [!] negate
[ ]     - Mandatory Value1(Int/Flt/Bool/VarName/FuncName)
[ ]     - Optional operator [< <= > >= == !=] and Value2(Int/Flt/Bool/VarName/FuncName)
[ ]     AllConditions(...) : SUCCESS if ( empty array || all conditions met)
[ ]     AnyConditions(...) : SUCCESS if (!empty array && one conditions met)

--- DECORATOR NODES

[ ] Cooldown Node: Decorator node that adds a cooldown period between the execution of a child node, preventing it from being executed again until the cooldown period has elapsed.
[x] Counter Node: Decorator node that limits the number of times that a child node can execute. For example, if the child node has executed a certain number of times, the Counter node will return a failure.
[x]     Once Node: Decorator node that triggers a specified action when a condition is met for the first time. This can be useful for triggering a one-time event, such as when an AI agent discovers a hidden item or reaches a new area of the game world.
[x] Inverter Node: Decorator node that inverts the result of a child node, returning success if the child node fails and failure if the child node succeeds. This can be useful for negating the outcome of a particular behavior, such as avoiding a certain area of the game world.
[x] Repeater Node: Decorator node that repeats the execution of a child node a specified number of times or indefinitely.
[x]     Repeat(times=inf): Runs child node given times. These are often used at the very base of the tree, to make the tree to run continuously.
[ ]         RepeatIf(strong/weak condition): Runs child node as long as the conditions are met.
[ ]         RepeatIfOk(times=inf): Runs child node if it succeedes, max given times.
[ ]         RepeatIfFail(times=inf): Runs child node if it fails, max given times.
[ ] Branch Node: 2 children [0] for true, [1] for false
[ ]     Resource Node: Decorator node that manages a shared resource, such as a limited supply of ammunition or a limited amount of processing power. The Resource node The node can be used to decide when to use or conserve the resource. For example, if the AI agent is low on ammunition, the node may decide to switch to a melee weapon or to retreat to a safer location. This node can be useful for implementing behaviors that require the AI agent to make strategic decisions about resource use.
[x] Result Node: Decorator node that tracks the result of a child action node and returns either success or failure depending on the outcome. This can be useful for determining whether an action was successful or not, and then adjusting the AI agent's behavior accordingly.
[x]     Succeeder Node: Decorator node that always returns success, regardless of the result of its child node. This can be useful for ensuring that certain behaviors are always executed, regardless of the overall success or failure of the behavior tree.
[x]     Success(): FAILURE becomes SUCCESS (TRUE).
[x]     Failure(): SUCCESS becomes FAILURE (FALSE).
[ ] Throttle Node: Decorator node that limits the rate at which a child node can execute. For example, a Throttle node might ensure that an AI agent can only fire its weapon, or using a special ability, only a certain number of times per second.
[x] Delay Node: Decorator node that adds a delay to the execution of a child node. The delay might be configured to sleep before the execution, after the execution, or both.
[x]     Defer Delay(duration_ss=1): Runs the child node, then sleeps for given seconds.
[ ] Ease(time,name): Clamps child time to [0,1] range, and applies easing function on it.
[ ] Dilate(Mul=1,Add=0): Dilates child time

--- CONTROL NODES

[x] Root Node: The topmost node in a behavior tree that represents the start of the decision-making process. Returns success if any of its child nodes suceedes.
[x] Root-Failure Node: Control node that only returns failure if all of its child nodes fail. This can be useful for ensuring that a behavior tree is not prematurely terminated if one or more child nodes fail.

[ ] Event(name): When name event is raised, it suspends current tree and calls child. "Incoming projectile" -> Evade. Stimulus types: may be disabled by event, or autodisabled.
[ ] Raise(name): Triggers event name.

[ ] Checkpoint Node: Control node that saves a state in memory and then continues the tree execution from that point the next time the tree is executed. It can be useful in situations where the behavior tree needs to be interrupted and resumed later.
[ ] Decision Making Node: Control node that implements a decision-making process for the AI agent. The node takes input specifying the available options for the AI agent and the criteria for evaluating each option. The node then evaluates each option based on the specified criteria and selects the best option. This node can be useful for implementing behaviors that require the AI agent to make strategic decisions, such as choosing a target or selecting a path through the game world.
[ ]     Could be extended with GOAP if dynamically inserting the scores on each update then calling a Probability Selector Node (0.2,0.3,0.5)
[ ]     https://cdn.cloudflare.steamstatic.com/apps/valve/2012/GDC2012_Ruskin_Elan_DynamicDialog.pdf
[ ] Evaluate Node / Recheck():
[ ]     Actively rechecks all existing sub-conditions on a regular basis after having made decisions about them.
[ ]     Use this feature to dynamically check for risks or opportunities in selected parts of the tree.
[ ]     For example, interrupting a patrol with a search behavior if a disturbance is reported.
[ ] Interrupt Node: Control node that interrupts the execution of a lower-priority node when a higher-priority node needs to be executed. It can be useful for handling urgent tasks or emergency situations.
[ ] Monitor Node: Control node that continuously monitors a condition and triggers a specified action when the condition is met. For example, a Monitor node might monitor the distance between an AI agent and a target and trigger a "retreat" behavior when the distance falls below a certain threshold.
[ ]     Observer Node: Control node that monitors the state of the game world and triggers a specified action when certain conditions are met. For example, an Observer node might trigger a "hide" behavior when an enemy is spotted.
[ ] Parallel Node: Control node that executes multiple child nodes simultaneously. The Parallel node continues to execute even if some of its child nodes fail.
[ ]     Parallel All Node(required_successes=100%): Control node that executes multiple child nodes simultaneously. Returns false when first child fails, and aborts any other running tasks. Returns true if all its children succeed.
[ ]     Parallel One Node(required_successes=1): Control node that executes multiple child nodes simultaneously. Returns true when first child suceedes, and aborts any other running tasks. Returns false if all its children fail.
[ ]     Subsumption Node: Control node that allows multiple behaviors to be executed simultaneously, with higher-priority behaviors taking precedence over lower-priority ones. This can be useful for implementing complex, multi-level behaviors in autonomous systems.
[ ] Semaphore Node: Control node that blocks the execution of its child nodes until a certain condition is met. For example, a Semaphore node might block the execution of a behavior until a certain object is in range or a certain event occurs.
[ ] Semaphore Wait Node: Control node that blocks the execution of its child nodes until a resource becomes available. This can be useful for controlling access to shared resources such as a pathfinding system or a communication channel.
[ ]     WaitTags(tags=blank,timeout_ss=inf): Stops execution of child node until the cooldown tag(s) do expire. May return earlier if timed out.
[ ]     WaitEvent(name=blank,timeout_ss=inf): Stops execution of child node until event is raised. May return earlier if timed out.
[x] Sequence Node(reversed,iterator(From,To)): Control node that executes a series of child nodes in order. If any of the child nodes fail, the Sequence node stops executing and returns a failure.
[ ]     Dynamic Sequence Node: Control node that dynamically changes the order in which its child nodes are executed based on certain conditions. For example, a Dynamic Sequence node might give higher priority to a child node that has recently failed or that is more likely to succeed.
[ ]     Reverse(): iterates children in reversed order (Iterator:(-1,0) equivalent)
[ ]     Iterator(from,to): allows negative indexing. increments if (abs from < abs to), decrements otherwise
[x] Selector Node: Control node that selects a child node to execute based on a predefined priority or set of conditions. The Selector node stops executing child nodes as soon as one of them succeeds.
[ ]     Priority Selector Node: Control node that executes its child nodes in order of priority. If the first child node fails, it moves on to the next child node in the list until a successful node is found. This can be useful for implementing behaviors that require a specific order of execution, such as a patrol route or a search pattern.
[ ]     Probability Selector Node: Control node that selects a child node to execute based on a probability distribution. For example, if there are three child nodes with probabilities of 0.2, 0.3, and 0.5, the Probability Selector node will execute the third child node 50% of the time.
[ ]     Dynamic Selector Node: Control node that dynamically changes the order in which its child nodes are executed based on certain conditions. For example, a Dynamic Selector node might give higher priority to a child node that has recently succeeded or that is more likely to succeed.
[ ]         Dynamic Selector Node: Control node that dynamically changes the order in which child nodes are executed based on certain conditions. For example, it may prioritize certain nodes when health is low, and other nodes when resources are scarce.
[ ]         Dynamic Priority Node: Control node that dynamically changes the priority of its child nodes based on certain conditions. For example, if a child node is more likely to result in success, the Dynamic Priority node will give it a higher priority.
[ ]     Weighted / Cover Selection Node: This is a type of selector node that evaluates the available cover options in the game world and selects the best cover position for the AI agent. The node takes input specifying the current position of the AI agent and the location of potential cover positions. The node then evaluates the cover positions based on criteria such as distance to enemy positions, line of sight, and available cover points, and selects the best option. This node can be useful for implementing behaviors that require the AI agent to take cover and avoid enemy fire.
[ ]     Random Selector Node: Control node that selects a child node to execute at random. This can be useful for introducing variety and unpredictability into the behavior of an AI agent.
[ ]     Random Weight / Stochastic Node(0.2,0.3,0.5): Control node that introduces randomness into the decision-making process of an AI agent. For example, a Stochastic node might randomly select a child node to execute, with the probability of each child node being proportional to its likelihood of success.
[ ] Break(bool): breaks parent sequence or selector. may return SUCCESS or FAILURE.
[ ] Hybrid Node: Control node that combines the functionality of multiple control nodes, such as a sequence node and a selector node. It can be useful for creating complex behavior patterns that require multiple control structures. The Hybrid Node has two modes of operation: strict mode and flexible mode. In strict mode, the child nodes are executed in a fixed order, similar to a Sequence Node. If any child node fails, the entire Hybrid Node fails. In flexible mode, the child nodes can be executed in any order, similar to a Selector Node. If any child node succeeds, the entire Hybrid Node succeeds. The Hybrid Node is often used when you need to create complex behavior patterns that require multiple control structures. For example, you might use a Hybrid Node to implement a search behavior where the AI agent first moves in a fixed direction for a certain distance (strict mode), but then switches to a more exploratory mode where it randomly explores nearby areas (flexible mode).
[ ] Subtree Node: Control node that calls another behavior tree as a subroutine. This is useful for breaking down complex behaviors into smaller, more manageable parts.
[ ]     Call(name): Calls to the child node with the matching name within behavior tree. Returns FAILURE if name is invalid or if invoked behavior returns FAILURE.
[ ]     Return(boolean): Exits current Call.
[ ]     AttachTree(Name,bDetachAfterUse=true): Attaches subtree to main tree. When a NPC founds the actor, it attaches the behavior to the tree. Ie, Level specific content: Patrols, Initial setups, Story driven events, etc. Ie, DLCs: Behaviors are added to actors in the DLC level (enticers).
[ ]     DetachTree(Name)
[ ] Switch Node: Control node that evaluates a condition and then selects one of several possible child nodes to execute based on the result of the condition.
[ ]     Switch(name): Jumps to the child node with the matching name within behavior tree. If name is invalid will defer to Fallback child node.
[ ] Timeout Node: Control node that aborts the execution of its child node after a certain amount of time has elapsed. This can be useful for preventing an AI agent from getting stuck in a loop or waiting indefinitely for a particular event to occur.
[ ]     TimeLimit(timeout_ss=inf): Give the child any amount of time to finish before it gets canceled. The timer is reset every time the node gains focus.
[ ] Timer Node: Control node which invokes its child node every XX seconds. The timer can repeat the action any given number of times, or indefinitely.

## Proposal -----------------------------------------------------------------------------

BehaviorTrees as case-insensitive INI files. Then,
- INI -> C INTERPRETER, OR
- INI -> LUA TRANSPILER -> LUA BYTECODE -> LUA VM.

```ini
[bt]
recheck
sequence                                  ;; Approach the player if seen!
 conditions=IsPlayerVisible,
 action=MoveTowardsPlayer
sequence                                  ;; Attack the player if seen!
 conditions=IsPlayerInRange,
 repeat=3
 action=FireAtPlayer
sequence                                  ;; Search near last known position
 conditions=HaveWeGotASuspectedLocation,
 action=MoveToPlayersLastKnownPosition
 action=LookAround
sequence                                  ;; Randomly scanning nearby
 action=MoveToRandomPosition
 action=LookAround
event=IncomingProjectile
 action=Evade
```

#endif

typedef int (*bt_func)();

typedef struct bt_t {
    uint64_t type;
    int (*action)();
    union {
        int argi;
        float argf;
    };
    array(struct bt_t) children;
} bt_t;

API bt_t    bt(const char *ini_file, unsigned flags);
API int     bt_run(bt_t *b);
API void    bt_addfun(const char *name, int(*func)());
API bt_func bt_findfun(const char *name);
API char   *bt_funcname(bt_func fn);

API void ui_bt(bt_t *b);
#line 0

#line 1 "v4k_audio.h"
// -----------------------------------------------------------------------------
// audio framework
// - rlyeh, public domain
//
// fixme: leaks, audio_delete
// @todo: audio_volume_fx, audio_volume_bgm, audio_volume_master instead?
// @todo: destroystream()    if( ss->type == WAV ) drwav_uninit(&ss->wav);
// @todo: destroystream()    if( ss->type == MOD ) jar_mod_unload(&ss->mod);
// @todo: destroystream()    if( ss->type == XM && ss->xm ) jar_xm_free_context(ss->xm);

// midi interface

API void    midi_send(unsigned midi_msg);

// audio interface

typedef struct audio_handle* audio_t;

API audio_t audio_clip( const char *pathfile );
API audio_t audio_stream( const char *pathfile );
API int     audio_play( audio_t s, int flags );
API int     audio_play_gain( audio_t a, int flags, float gain/*0*/ );
API int     audio_play_gain_pitch( audio_t a, int flags, float gain, float pitch/*1*/ );
API int     audio_play_gain_pitch_pan( audio_t a, int flags, float gain, float pitch, float pan/*0*/ );
API int     audio_stop( audio_t a );

API float   audio_volume_clip(float gain);   // set     fx volume if gain is in [0..1] range. return current     fx volume in any case
API float   audio_volume_stream(float gain); // set    bgm volume if gain is in [0..1] range. return current    bgm volume in any case
API float   audio_volume_master(float gain); // set master volume if gain is in [0..1] range. return current master volume in any case

enum AUDIO_FLAGS {
    AUDIO_1CH = 0, // default
    AUDIO_2CH = 1,

    AUDIO_8 = 2,
    AUDIO_16 = 0, // default
    AUDIO_32 = 4,
    AUDIO_FLOAT = 8,

    AUDIO_8KHZ = 16,
    AUDIO_11KHZ = 32,
    AUDIO_22KHZ = 0, // default
    AUDIO_32KHZ = 64,
    AUDIO_44KHZ = 128,

    AUDIO_MIXER_GAIN = 0, // default
    AUDIO_IGNORE_MIXER_GAIN = 256,

    AUDIO_MULTIPLE_INSTANCES = 0, // default
    AUDIO_SINGLE_INSTANCE = 512,
};

API int audio_queue( const void *samples, int num_samples, int flags );
#line 0

#line 1 "v4k_collide.h"
// -----------------------------------------------------------------------------
// original code by @vurtun (PD) and @barerose (CC0).
// [src] https://gist.github.com/vurtun/95f088e4889da2474ad1ce82d7911fee
// - rlyeh, public domain.

#ifndef GJK_H
#define GJK_H

#define GJK_MAX_ITERATIONS 20

typedef struct gjk_support {
    int aid, bid;
    vec3 a;
    vec3 b;
} gjk_support;
typedef struct gjk_vertex {
    vec3 a;
    vec3 b;
    vec3 p;
    int aid, bid;
} gjk_vertex;
typedef struct gjk_simplex {
    int max_iter, iter;
    int hit, cnt;
    gjk_vertex v[4];
    float bc[4], D;
} gjk_simplex;
typedef struct gjk_result {
    int hit;
    vec3 p0;
    vec3 p1;
    float distance_squared;
    int iterations;
} gjk_result;

int gjk(gjk_simplex *s, const gjk_support *sup, vec3 *dv);
gjk_result gjk_analyze(const gjk_simplex *s);
gjk_result gjk_quad(float a_radius, float b_radius);

#endif

//typedef struct gjk_result gjk_result;

typedef struct line     { vec3 a, b;                                                  } line;
typedef struct sphere   { vec3 c; float r;                                            } sphere;
typedef struct aabb     { vec3 min, max;                                              } aabb;
typedef struct plane    { vec3 p, n;                                                  } plane;
typedef struct capsule  { vec3 a, b; float r;                                         } capsule;
typedef struct ray      { vec3 p, d;                                                  } ray;
typedef struct triangle { vec3 p0,p1,p2;                                              } triangle;
typedef struct poly     { vec3* verts; int cnt;                                       } poly;
typedef union  frustum  { struct { vec4 l, r, t, b, n, f; }; vec4 pl[6]; float v[24]; } frustum;

#define line(...)       C_CAST(line, __VA_ARGS__)
#define sphere(...)     C_CAST(sphere, __VA_ARGS__)
#define aabb(...)       C_CAST(aabb, __VA_ARGS__)
#define plane(...)      C_CAST(plane, __VA_ARGS__)
#define capsule(...)    C_CAST(capsule, __VA_ARGS__)
#define ray(p,normdir)  C_CAST(ray, p, normdir)
#define triangle(...)   C_CAST(triangle, __VA_ARGS__)
#define poly(...)       C_CAST(poly, __VA_ARGS__)
#define frustum(...)    C_CAST(frustum, __VA_ARGS__)

// ----------------------------------------------------------------------------

typedef struct hit {
    union {
        // general case
        float depth;
        // rays only: penetration (t0) and extraction (t1) points along ray line
        struct { float t0, t1; };
        // gjk only
        struct { int hits; vec3 p0, p1; float distance2; int iterations; };
    };
    union { vec3 p; vec3 contact_point; };
    union { vec3 n; vec3 normal; };
} hit;

#define hit(...)        C_CAST(hit, __VA_ARGS__)

// ----------------------------------------------------------------------------

/* line/segment */
API float   line_distance2_point(line l, vec3 p);
API vec3    line_closest_point(line l, vec3 p);
/* ray */
API float   ray_test_plane(ray r, vec4 p4);
API float   ray_test_triangle(ray r, triangle t);
API int     ray_test_sphere(float *t0, float *t1, ray r, sphere s);
API int     ray_test_aabb(float *t0, float *t1, ray r, aabb a);
API hit*    ray_hit_plane(ray r, plane p);
API hit*    ray_hit_triangle(ray r, triangle t);
API hit*    ray_hit_sphere(ray r, sphere s);
API hit*    ray_hit_aabb(ray r, aabb a);
/* sphere */
API vec3    sphere_closest_point(sphere s, vec3 p);
API hit*    sphere_hit_aabb(sphere s, aabb a);
API hit*    sphere_hit_capsule(sphere s, capsule c);
API hit*    sphere_hit_sphere(sphere a, sphere b);
API int     sphere_test_aabb(sphere s, aabb a);
API int     sphere_test_capsule(sphere s, capsule c);
API int     sphere_test_poly(sphere s, poly p);
API int     sphere_test_sphere(sphere a, sphere b);
/* aabb */
API vec3    aabb_closest_point(aabb a, vec3 p);
API float   aabb_distance2_point(aabb a, vec3 p);
API int     aabb_contains_point(aabb a, vec3 p);
API hit*    aabb_hit_aabb(aabb a, aabb b);
API hit*    aabb_hit_capsule(aabb a, capsule c);
API hit*    aabb_hit_sphere(aabb a, sphere s);
API int     aabb_test_aabb(aabb a, aabb b);
API int     aabb_test_capsule(aabb a, capsule c);
API int     aabb_test_poly(aabb a, poly p);
API int     aabb_test_sphere(aabb a, sphere s);
/* capsule */
API float   capsule_distance2_point(capsule c, vec3 p);
API vec3    capsule_closest_point(capsule c, vec3 p);
API hit*    capsule_hit_aabb(capsule c, aabb a);
API hit*    capsule_hit_capsule(capsule a, capsule b);
API hit*    capsule_hit_sphere(capsule c, sphere s);
API int     capsule_test_aabb(capsule c, aabb a);
API int     capsule_test_capsule(capsule a, capsule b);
API int     capsule_test_poly(capsule c, poly p);
API int     capsule_test_sphere(capsule c, sphere s);
/* poly: query */
API int     poly_test_sphere(poly p, sphere s);
API int     poly_test_aabb(poly p, aabb a);
API int     poly_test_capsule(poly p, capsule c);
API int     poly_test_poly(poly a, poly b);
/* poly: query transformed */
API int     poly_test_sphere_transform(poly p, vec3 pos3, mat33 rot33, sphere s);
API int     poly_test_aabb_transform(poly p, vec3 apos3, mat33 arot33, aabb a);
API int     poly_test_capsule_transform(poly p, vec3 pos3, mat33 rot33, capsule c);
API int     poly_test_poly_transform(poly a, vec3 apos3, mat33 arot33, poly b, vec3 bpos3, mat33 brot33);
/* poly: gjk result */
API int     poly_hit_sphere(struct gjk_result *res, poly p, sphere s);
API int     poly_hit_aabb(struct gjk_result *res, poly p, aabb a);
API int     poly_hit_capsule(struct gjk_result *res, poly p, capsule c);
API int     poly_hit_poly(struct gjk_result *res, poly a, poly b);
/* poly: gjk result transformed */
API int     poly_hit_sphere_transform(struct gjk_result *res, poly p, vec3 pos3, mat33 rot33, sphere s);
API int     poly_hit_aabb_transform(struct gjk_result *res, poly p, vec3 pos3, mat33 rot33, aabb a);
API int     poly_hit_capsule_transform(struct gjk_result *res, poly p, vec3 pos3, mat33 rot33, capsule c);
API int     poly_hit_poly_transform(struct gjk_result *res, poly a, vec3 at3, mat33 ar33, poly b, vec3 bt3, mat33 br33);

API vec4    plane4(vec3 p, vec3 n);

API frustum frustum_build(mat44 projview);
API int     frustum_test_sphere(frustum f, sphere s);
API int     frustum_test_aabb(frustum f, aabb a);

API poly    poly_alloc(int cnt);
API void    poly_free(poly *p);

API poly    pyramid(vec3 from, vec3 to, float size); // poly_free() required
API poly    diamond(vec3 from, vec3 to, float size); // poly_free() required

API void    collide_demo(); // debug draw collisions
#line 0

#line 1 "v4k_cooker.h"
// -----------------------------------------------------------------------------
// asset pipeline framework
// - rlyeh, public domain.
//
// all cooked assets are stored inside zip file at root folder, which acts as an asset database.
// during game boot, the database gets rebuilt as follows: (note: step 0 is an optional optimization)
// 0. for N given cores, split list of infiles into N zipfiles. then, parallelize cooks.
// 1. compare local disk files against file in zip database. for each mismatch do:
// 2. - invalidate its entry in database, if local file was removed from disk.
// 3. - write its *cooked* contents into database, if local file was created or modified from disk.
// 4. mount any existing zipfile(s) after cooking.
//
// notes: meta-datas from every raw asset are stored into comment field, inside .cook.zip archive.
// @todo: fix leaks
// @todo: symlink exact files
// @todo: idle threads should steal jobs from busy threads (maybe use jobs/coroutines for this?) ...

enum COOK_FLAGS {
    COOK_SYNC = 0,
    COOK_ASYNC = 1,
    COOK_CANCELABLE = 2,
    COOK_DEBUGLOG = 4, // log all cooking commands to a batch file
};

API void cook_config( const char *path_to_cook_ini ); // "tools/cook.ini"
API bool cook_start( const char *path_to_cook_ini, const char *masks, int flags ); // COOK_INI, "**"
API void cook_stop();
API void cook_cancel();
API int  cook_jobs();     // [0..N]
API int  cook_progress(); // [0..100]

#line 0

#line 1 "v4k_data.h"
// -----------------------------------------------------------------------------
// data framework (json5, xml, compression) @todo:kvdb
// - rlyeh, public domain
//
// @todo: vec2,vec3,vec4

typedef union json_t { char* s; double f; int64_t i; uintptr_t p; array(union json_t) arr; } json_t;

// json api

API bool            json_push(const char *json_content);
API const char*         json_key(const char *keypath);
API json_t*             json_find(const char *type_keypath);
API json_t              json_get(const char *type_keypath);
API int                 json_count(const char *keypath);
#define                 json_int(...)    (json_get(va("i" __VA_ARGS__)).i)
#define                 json_float(...)  (json_get(va("f" __VA_ARGS__)).f)
#define                 json_string(...) (json_get(va("s" __VA_ARGS__)).s)
#define                 json_key(...)     json_key(va(__VA_ARGS__))
#define                 json_count(...)   json_count(va(__VA_ARGS__))
API bool            json_pop();

// xml api

API int             xml_push(const char *xml_content);
API const char *        xml_string(char *key);
API unsigned            xml_count(char *key);
API array(char)         xml_blob(char *key);
#define                 xml_string(...) xml_string(va(__VA_ARGS__))       // syntax sugar: string
#define                 xml_int(...)    atoi(xml_string(__VA_ARGS__))     // syntax sugar: int
#define                 xml_float(...)  atof(xml_string(__VA_ARGS__))     // syntax sugar: float
#define                 xml_blob(...)   xml_blob(va(__VA_ARGS__))         // syntax sugar: base64 blob
#define                 xml_count(...)  xml_count(va(__VA_ARGS__))        // syntax sugar: count nodes
API void            xml_pop();

API bool data_tests();

// compression api

enum COMPRESS_FLAGS {
    COMPRESS_RAW     = 0,
    COMPRESS_PPP     = (1<<4),
    COMPRESS_ULZ     = (2<<4),
    COMPRESS_LZ4     = (3<<4),
    COMPRESS_CRUSH   = (4<<4),
    COMPRESS_DEFLATE = (5<<4),
    COMPRESS_LZP1    = (6<<4),
    COMPRESS_LZMA    = (7<<4),
    COMPRESS_BALZ    = (8<<4),
    COMPRESS_LZW3    = (9<<4),
    COMPRESS_LZSS    = (10<<4),
    COMPRESS_BCM     = (11<<4),
    COMPRESS_ZLIB    = (12<<4), // same as deflate with header
};

API unsigned zbounds(unsigned inlen, unsigned flags);
API unsigned zencode(void *out, unsigned outlen, const void *in, unsigned inlen, unsigned flags);
API unsigned zexcess(unsigned flags);
API unsigned zdecode(void *out, unsigned outlen, const void *in, unsigned inlen, unsigned flags);
#line 0

#line 1 "v4k_dll.h"
// dll utils
// - rlyeh, public domain

/// !!! `filename` must contain extension
/// load dynamic library `file` and search for `symbol`
/// return: NULL if not found, found symbol otherwise.
/// filename: path to dynamic library file. must contain extension.
/// symbol: symbol name. must not be NULL.
/// see: dlopen^, dlclose^
/// > bool (*plugin_init)(void) = dll("plugin.dll", "init");
/// > assert(plugin_init());
API void* dll(const char *filename, const char *symbol);
#line 0

#line 1 "v4k_editor.h"
// -----------------------------------------------------------------------------
// in-game editor
// - rlyeh, public domain.
//
// @todo: merge editor1.c and editor2.c internals into this api

//API void  editor();
//API bool  editor_active();
API vec3  editor_pick(float mouse_x, float mouse_y);
API char* editor_path(const char *path);

// open file dialog

API char* dialog_load();
API char* dialog_save();

// transform gizmos

API int   gizmo(vec3 *pos, vec3 *rot, vec3 *sca);
API bool  gizmo_active();
API bool  gizmo_hover();

// localization kit (I18N, L10N)

API void  kit_locale( const char *langcode_iso639_1 ); // set context language: enUS, ptBR, esES, ...
API void  kit_set( const char *variable, const char *value ); // set context variable
API void  kit_reset(); // reset all variables in context

API void  kit_insert( const char *id, const char *translation ); // insert single translation
API bool  kit_load( const char *filename ); // load translations file (xlsx)
API bool  kit_merge( const char *filename ); // merge translations file into existing context
API void  kit_clear(); // delete all translations

API char* kit_translate( const char *id ); // perform a translation, given current locale
API char* kit_translate2( const char *id, const char *langcode_iso639_1 ); // perform a translation given explicit locale

API void  kit_dump_state( FILE *fp );
#line 0

#line 1 "v4k_file.h"
// -----------------------------------------------------------------------------
// files, cache and virtual filesystem (registered directories and/or compressed zip archives).
// - rlyeh, public domain.
//
// - note: vfs_mount() order matters (last mounts have higher priority).
// - note: directory/with/trailing/slash/ as mount_point, or zip/tar/pak archive otherwise.
//
// @todo: file_mmap
// @todo: file_find() from first file_scan()

// physical filesystem. files

API const char** file_list(const char *path, const char *masks); // **.png;*.c
API bool         file_write( const char *file, const void *ptr, int len );
API bool         file_append( const char *file, const void *ptr, int len );
API char *       file_read(const char *filename);
API char *       file_load(const char *filename, int *len);
API uint64_t     file_size(const char *pathfile);
API bool         file_directory(const char *pathfile);

API char *       file_pathabs(const char *pathfile); // ../dir/./file.ext -> c:/prj/dir/file.ext
API char *       file_path(const char *pathfile); // c:/prj/dir/file.ext -> c:/prj/dir/
API char *       file_name(const char *pathfile); // c:/prj/dir/file.ext -> file.ext
API char *       file_base(const char *pathfile); // c:/prj/dir/file.ext -> file
API char *       file_ext(const char *pathfile); // c:/prj/dir/file.ext -> .ext
API char *       file_id(const char *pathfile); // c:/prj/dir/file.ext -> file/dir/prj (name then alphabetical)
API char *       file_normalize(const char *pathfile); // c:/prj/dir/file.ext -> c/prj/dir/file_ext
//API char *     file_normalize_with_folder(const char *pathfile); // c:/prj/dir/file.ext -> dir/file_ext
API char *       file_counter(const char *pathfile); // in: v4k.ini -> out: v4k(001).ini -> out: v4k(002).ini [-> etc...]

API uint64_t     file_stamp(const char *pathfile); // 1616153596 (seconds since unix epoch)
API uint64_t     file_stamp10(const char *pathfile); // 20210319113316 (absolute datetime in base10)

API bool         file_exist(const char *pathfile);
API bool         file_delete(const char *pathfile);
API bool         file_copy(const char *src, const char *dst);
API bool         file_move(const char *src, const char *dst);

API FILE*        file_temp();
API char*        file_tempname();

API void*        file_md5(const char *file); // 16 bytes
API void*        file_sha1(const char *file); // 20 bytes
API void*        file_crc32(const char *file); // 4 bytes

// compressed files

API array(char*) file_zip_list(const char *zipfile);
API array(char)  file_zip_extract(const char *zipfile, const char *filename);
API bool         file_zip_append(const char *zipfile, const char *filename, int clevel);
API bool         file_zip_appendmem(const char *zipfile, const char *entryname, const void *ptr, unsigned len, int clevel);

// storage (emscripten only)

// Mounts local storage folder for writing. Useful for Emscripten only. @path_folder: "/save" for example
// Reads local storage to memory. Usually call it one time only, after mount. Useful for Emscripten only.
// Writes memory contents to local storage. Usually call it after all fclose
API void         storage_mount(const char* folder);
API void         storage_read();
API void         storage_flush();

// virtual filesystem

API bool         vfs_mount(const char *mount_point);
API const char** vfs_list(const char *masks); // **.png;*.c

API char *       vfs_read(const char *pathfile);
API char *       vfs_load(const char *pathfile, int *size);
API int          vfs_size(const char *pathfile);

API const char * vfs_resolve(const char *fuzzyname); // guess best match. @todo: fuzzy path
//API const char*vfs_extract(const char *pathfile); // extracts vfs file into local filesystem (temporary file), so it can be read by foreign/3rd party libs
API FILE*        vfs_handle(const char *pathfile); // same as above, but returns file handle instead. preferred way, will clean descriptors at exit

// cache

API void *       cache_insert(const char *key, void *value, int size);
API void *       cache_lookup(const char *key, int *size);

// ini

// @todo: evaluate alt api #1
// char *ini(filename, section.key, default);
// float inif(filename, section.key, default);
// @todo: evaluate alt api #2
// char *val = ini(filename, section_key);
// int count = ini_count(filename);
// char *key = ini_key_id(filename, id);
// char *val = ini_val_id(filename, id);

typedef map(char*,char*) ini_t;

API ini_t        ini(const char *filename);
API ini_t        ini_from_mem(const char *data);
API void         ini_destroy(ini_t);

API bool         ini_write(const char *filename, const char *section, const char *key, const char *value);
#line 0

#line 1 "v4k_font.h"
// -----------------------------------------------------------------------------
// font framework
// - rlyeh, public domain

// font size tags
#define FONT_H1 "\1" // largest
#define FONT_H2 "\2"
#define FONT_H3 "\3"
#define FONT_H4 "\4"
#define FONT_H5 "\5"
#define FONT_H6 "\6" // smallest

// font color tags
#define FONT_COLOR1  "\x10"
#define FONT_COLOR2  "\x11"
#define FONT_COLOR3  "\x12"
#define FONT_COLOR4  "\x13"
#define FONT_COLOR5  "\x14"
#define FONT_COLOR6  "\x15"
#define FONT_COLOR7  "\x16"
#define FONT_COLOR8  "\x17"
#define FONT_COLOR9  "\x18"
#define FONT_COLOR10 "\x19"

// font face tags
#define FONT_FACE1   "\x1a"
#define FONT_FACE2   "\x1b"
#define FONT_FACE3   "\x1c"
#define FONT_FACE4   "\x1d"
#define FONT_FACE5   "\x1e"
#define FONT_FACE6   "\x1f"

// font align tags
#define FONT_LEFT     "\\<"
#define FONT_CENTER   "\\|"
#define FONT_RIGHT    "\\>"
#define FONT_TOP      "\\^"
#define FONT_MIDDLE   "\\-"
#define FONT_BASELINE "\\_"
#define FONT_BOTTOM   "\\v"

// font flags
enum FONT_FLAGS {
    // font atlas size
    FONT_512 = 0x0,
    FONT_1024 = 0x1,
    FONT_2048 = 0x2,
    FONT_4096 = 0x4,

    // font oversampling
    FONT_NO_OVERSAMPLE = 0x0,
    FONT_OVERSAMPLE_X = 0x08,
    FONT_OVERSAMPLE_Y = 0x10,

    // unicode ranges
    FONT_ASCII = 0x800, // Compatible charset
    FONT_AR = 0x001000, // Arabic and Arabic-Indic digits
    FONT_ZH = 0x002000, // Chinese Simplified (@todo: add ZH_FULL)
    FONT_EL = 0x004000, // Greek, Coptic, modern Georgian, Svan, Mingrelian, Ancient Greek
    FONT_EM = 0x008000, // Emoji
    FONT_EU = 0x010000, // Eastern/western Europe, IPA, Latin ext A/B
    FONT_HE = 0x020000, // Hebrew, Yiddish, Ladino, and other diaspora languages
    FONT_JP = 0x040000, // Hiragana, Katakana, Punctuations, Half-width chars
    FONT_KR = 0x080000, // Korean, Hangul
    FONT_RU = 0x100000, // Cyrillic + ext A/B
    FONT_TH = 0x200000, // Thai
    FONT_VI = 0x400000, // Vietnamese
    FONT_CJK = FONT_ZH|FONT_JP|FONT_KR,

    // FONT_DEFAULTS = FONT_512 | FONT_NO_OVERSAMPLE | FONT_ASCII,
};

// configures
API void  font_face(const char *face_tag, const char *filename_ttf, float font_size, unsigned flags);
API void  font_face_from_mem(const char *tag, const void *ttf_buffer, unsigned ttf_len, float font_size, unsigned flags);
API void  font_scales(const char *face_tag, float h1, float h2, float h3, float h4, float h5, float h6);
API void  font_color(const char *color_tag, uint32_t color);

// commands
API vec2  font_xy();
API void  font_goto(float x, float y);
API vec2  font_print(const char *text);
API vec2  font_rect(const char *text);
//  void  font_clip(vec2 topleft, vec2 bottomright);
//  void  font_wrap(vec2 topleft, vec2 bottomright);

// syntax highlighting
API void* font_colorize(const char *text, const char *comma_types, const char *comma_keywords); // comma separated tokens. expensive, please cache result.
API vec2  font_highlight(const char *text, const void *colors);
#line 0

#line 1 "v4k_input.h"
// -----------------------------------------------------------------------------
// input framework
// - rlyeh, public domain
//
// @todo: window
// @todo: for extra savings (168->72 bytes), promote bits to real bits (/8 %8) & normalized floats [-1,+1] to shorts or chars
// @todo: GAMEPAD_A|2, MOUSE_L|1, KEY_C|3
// @todo: load/save
// @todo: send virtual presses & outputs (rumble, light, led, text, etc)
// @todo: fix if logger !60 hz
// @tofo: fix click2/repeat edge cases

API int         input_use( int controller_id ); // [0..3]

// -- basic polling api (read input at current frame)

API float       input( int vk );
API vec2        input2( int vk );
API float       input_diff( int vk ); // @todo: rename diff->delta
API vec2        input_diff2( int vk ); // @todo: rename diff2->delta2

// -- extended polling api (read input at Nth frame ago)

API float       input_frame( int vk, int frame );
API vec2        input_frame2( int vk, int frame );
API const char* input_frames( int vk, int frame );

// -- events api

API int         input_up( int vk ); // ON -> OFF (release)
API int         input_down( int vk ); // OFF -> ON (trigger)
API int         input_held( int vk ); // ON -> ON (pressed)
API int         input_idle( int vk ); // OFF -> OFF

API int         input_click( int vk, int ms ); // OFF -> ON -> OFF
API int         input_click2( int vk, int ms ); // OFF -> ON -> OFF -> ON -> OFF
API int         input_repeat( int vk, int ms ); // [...] ON -> ON -> ON

API int         input_chord2( int vk1, int vk2 ); // all vk1 && vk2 are ON
API int         input_chord3( int vk1, int vk2, int vk3 ); // all vk1 && vk2 && vk3 are ON
API int         input_chord4( int vk1, int vk2, int vk3, int vk4 ); // all vk1 && vk2 && vk3 && vk4 are ON

// -- 1d/2d filters

API float       input_filter_positive( float v ); // [-1..1] -> [0..1]
API vec2        input_filter_positive2( vec2 v ); // [-1..1] -> [0..1]
API vec2        input_filter_deadzone( vec2 v, float deadzone_treshold );
API vec2        input_filter_deadzone_4way( vec2 v, float deadzone_treshold );

// -- multi-touch

enum TOUCH_BUTTONS {
    TOUCH_0,    // defaults to left screen area. input_touch_area() to override
    TOUCH_1,    // defaults to right screen area. input_touch_area() to override
};

API void        input_touch_area(unsigned button, vec2 begin_coord_ndc, vec2 end_coord_ndc);
API vec2        input_touch(unsigned button, float sensitivity);                   // absolute position in 2d coords
API vec2        input_touch_delta(unsigned button, float sensitivity);             // delta from previous position
API vec2        input_touch_delta_from_origin(unsigned button, float sensitivity); // relative position from initial touch
API bool        input_touch_active();

// -- utils

API void        input_demo();
API void        input_mappings(const char *filename); // update gamepad mappings (usually "gamecontrollerdb.txt" file)
API void        input_send( int vk ); // @todo
API void*       input_save_state( int id, int *size); // @todo
API bool        input_load_state( int id, void *ptr, int size); // @todo
API char        input_keychar(unsigned code); // Converts keyboard code to its latin char (if any)
API int         input_anykey();

// --

enum INPUT_ENUMS {
    // -- bits: x104 keyboard, x3 mouse, x15 gamepad, x7 window
    // keyboard gaming keys (53-bit): first-class keys for gaming
    KEY_ESC,
    KEY_TICK, KEY_1,KEY_2,KEY_3,KEY_4,KEY_5,KEY_6,KEY_7,KEY_8,KEY_9,KEY_0,  KEY_BS,
    KEY_TAB,   KEY_Q,KEY_W,KEY_E,KEY_R,KEY_T,KEY_Y,KEY_U,KEY_I,KEY_O,KEY_P,
    KEY_CAPS,     KEY_A,KEY_S,KEY_D,KEY_F,KEY_G,KEY_H,KEY_J,KEY_K,KEY_L, KEY_ENTER,
    KEY_LSHIFT,       KEY_Z,KEY_X,KEY_C,KEY_V,KEY_B,KEY_N,KEY_M,        KEY_RSHIFT,            KEY_UP,
    KEY_LCTRL,KEY_LALT,               KEY_SPACE,                KEY_RALT,KEY_RCTRL,  KEY_LEFT,KEY_DOWN,KEY_RIGHT,

    // for completeness, secondary keys below (52-bit). beware!
    KEY_INS,KEY_HOME,KEY_PGUP,KEY_DEL,KEY_END,KEY_PGDN, // beware: different behavior win/osx (also, osx: no home/end).
    KEY_LMETA,KEY_RMETA,KEY_MENU,KEY_PRINT,KEY_PAUSE,KEY_SCROLL,KEY_NUMLOCK, // beware: may trigger unexpected OS behavior. (@todo: add RSHIFT here for win?)
    KEY_MINUS,KEY_EQUAL,KEY_LSQUARE,KEY_RSQUARE,KEY_SEMICOLON,KEY_QUOTE,KEY_HASH,KEY_BAR,KEY_COMMA,KEY_DOT,KEY_SLASH, // beware: non-us keyboard layouts
    KEY_F1,KEY_F2,KEY_F3,KEY_F4,KEY_F5,KEY_F6,KEY_F7,KEY_F8,KEY_F9,KEY_F10,KEY_F11,KEY_F12, // beware: complicated on laptops/osx
    KEY_PAD1,KEY_PAD2,KEY_PAD3,KEY_PAD4,KEY_PAD5,KEY_PAD6,KEY_PAD7,KEY_PAD8,KEY_PAD9,KEY_PAD0, // beware: complicated on laptops
    KEY_PADADD,KEY_PADSUB,KEY_PADMUL,KEY_PADDIV,KEY_PADDOT,KEY_PADENTER, // beware: complicated on laptops

    MOUSE_L, MOUSE_M, MOUSE_R,
    GAMEPAD_CONNECTED, GAMEPAD_A, GAMEPAD_B, GAMEPAD_X, GAMEPAD_Y,
    GAMEPAD_UP, GAMEPAD_DOWN, GAMEPAD_LEFT, GAMEPAD_RIGHT, GAMEPAD_MENU, GAMEPAD_START,
    GAMEPAD_LB, GAMEPAD_RB, GAMEPAD_LTHUMB, GAMEPAD_RTHUMB,
    WINDOW_BLUR, WINDOW_FOCUS, WINDOW_CLOSE, WINDOW_MINIMIZE, WINDOW_MAXIMIZE, WINDOW_FULLSCREEN, WINDOW_WINDOWED, // MINI/MAXI/RESTORED, SHOWN/HIDDEN

    // -- floats: x7 gamepad, x3 mouse, x4 touch, x4 window
    GAMEPAD_LPAD, GAMEPAD_LPADX = GAMEPAD_LPAD, GAMEPAD_LPADY,
    GAMEPAD_RPAD, GAMEPAD_RPADX = GAMEPAD_RPAD, GAMEPAD_RPADY,
    GAMEPAD_LTRIGGER, GAMEPAD_LT = GAMEPAD_LTRIGGER, GAMEPAD_RTRIGGER, GAMEPAD_RT = GAMEPAD_RTRIGGER, GAMEPAD_BATTERY,
    MOUSE, MOUSE_X = MOUSE, MOUSE_Y, MOUSE_W,
    TOUCH_X1, TOUCH_Y1, TOUCH_X2, TOUCH_Y2,
    WINDOW_RESIZE, WINDOW_RESIZEX = WINDOW_RESIZE, WINDOW_RESIZEY, WINDOW_ORIENTATION, WINDOW_BATTERY,

    // -- strings: x2 gamepad
    GAMEPAD_GUID, GAMEPAD_NAME,
};
#line 0

#line 1 "v4k_memory.h"
// -----------------------------------------------------------------------------
// memory framework
// - rlyeh, public domain

// memory leaks detector
#if ENABLE_MEMORY_LEAKS
#define WATCH(ptr,sz) watch((ptr), (sz))
#define FORGET(ptr)   forget(ptr)
#else
#define WATCH(ptr,sz) (ptr)
#define FORGET(ptr)   (ptr)
#endif

// default allocator (aborts on out-of-mem)
API void*  xrealloc(void* p, size_t sz);
API size_t xsize(void* p);
API char*  xstats(void);

// stack based allocator (negative bytes does rewind stack, like when entering new frame)
API void*  stack(int bytes);

// memory leaks api (this is already integrated as long as you compile with -DENABLE_MEMORY_LEAKS)
API void*  watch( void *ptr, int sz );
API void*  forget( void *ptr );

// memory api
#define ALLOCSIZE(p)   xsize(p)
#define MALLOC(n)      REALLOC_(0,(n))
#define FREE(p)        REALLOC_((p), 0)
#define REALLOC(p,n)   REALLOC_((p),(n))
#define CALLOC(m,n)    CALLOC_((m),(n))
#define STRDUP(s)      STRDUP_(s)

static FORCE_INLINE void *(REALLOC_)(void *p, size_t n) { return n ? WATCH(xrealloc(p,n),n) : xrealloc(FORGET(p),0); } ///-
static FORCE_INLINE void *(CALLOC_)(size_t m, size_t n) { return n *= m, memset(REALLOC(0,n),0,n); } ///-
static FORCE_INLINE char *(STRDUP_)(const char *s) { size_t n = strlen(s)+1; return ((char*)memcpy(REALLOC(0,n), s, n)); } ///-
#line 0

#line 1 "v4k_network.h"
// -----------------------------------------------------------------------------
// network framework
// - rlyeh, public domain

API array(char) download( const char *url );
API int         download_file( FILE *out, const char *url );
API int         portname( const char *service_name, unsigned retries );

API bool        network_tests();

// -----------------------------------------------------------------------------
// udp wrapper
// - rlyeh, public domain.

// server
API int   udp_bind(const char *address, const char *port);

// client
API int   udp_open(const char *address, const char *port);

// common
API int   udp_send(int, const void *buf, int len ); // <0 error, >0 bytes sent ok
API int   udp_sendto(int, const char *ip, const char *port, const void *buf, int len ); // <0 error, >0 bytes sent ok
API int   udp_recv(int, void *buf, int len ); // <0 error, 0 orderly shutdown, >0 received bytes
API int   udp_peek(int); // <0 error, 0 timeout, >0 data

// -----------------------------------------------------------------------------
// tcp wrapper
// - rlyeh, public domain

// client
API int   tcp_open(const char *address, const char *port);

// server
API int   tcp_bind(const char *interface_, const char *port, int queue);
API int   tcp_peek(int, int(*callback)(int));

// common
API int   tcp_send(int, const void* buf, int len);
API int   tcp_recv(int, void* buf, int len);
API char* tcp_host(int); // info
API char* tcp_port(int); // info

API int   tcp_close(int);

// extras
API int   tcp_debug(int); // toggle traffic monitoring on/off for given socket
//API int   tcp_printf(int, const char *fmt, ...); // printf message in remote end
//API int   tcp_crypt(int,uint64_t);               // set shared secret
#line 0

#line 1 "v4k_netsync.h"
// high-level, socket-less networking api. inspired by Quake, MPI and RenderBuckets theories.
// - rlyeh, public domain
//
// Usage:
// 1. configure networked memory buffers with flags (world, player1, player2, etc). network_buffer();
// 2. then during game loop:
//    - modify your buffers as much as needed.
//    - sync buffers at least once per frame. network_sync();
//    - render your world
// 3. optionally, monitor network status & variables. network_get();
//
// @todo: maybe network_send(msg) + msg *network_recv(); instead of event queue of network_sync() ?

//enum { NETWORK_HANDSHAKE, NETWORK_ENCRYPT, NETWORK_VERSIONED, NETWORK_CHECKSUM }; // negotiation
//enum { NETWORK_TCP, NETWORK_UDP, NETWORK_KCP, NETWORK_ENET, NETWORK_WEBSOCKET }; // transport, where

enum { NETWORK_BIND = 2, NETWORK_CONNECT = 4, NETWORK_NOFAIL = 8 };
API void   network_create(unsigned max_clients, const char *ip, const char *port, unsigned flags); // both ip and port can be null

//enum { NETWORK_LOSSY, NETWORK_COMPRESS }; // post-processes
//enum { NETWORK_PREDICT, NETWORK_RECONCILE, NETWORK_INTERPOLATE, NETWORK_COMPENSATE }; // time authority, when
//enum { NETWORK_LAGS, NETWORK_DROPS, NETWORK_THROTTLES, NETWORK_DUPES }; // quality sim, how much
//enum { NETWORK_CONST = 1, NETWORK_64,NETWORK_32,NETWORK_16,NETWORK_8, NETWORK_FLT, NETWORK_STR, NETWORK_BLOB }; // type, what
enum { NETWORK_SEND = 2, NETWORK_RECV = 4 };
enum { NETWORK_UNRELIABLE = 8, NETWORK_UNORDERED = 16/*, NETWORK_PRIORITY = 32*/ };
API void*   network_buffer(void *ptr, unsigned sz, uint64_t flags, int64_t rank); // configures a shared/networked buffer
API char**  network_sync(unsigned timeout_ms); // syncs all buffers & returns null-terminated list of network events

enum {
    NETWORK_EVENT_CONNECT,
    NETWORK_EVENT_DISCONNECT,
    NETWORK_EVENT_RECEIVE,
    NETWORK_EVENT_DISCONNECT_TIMEOUT,

    /* offset from internal networking events */
    NETWORK_EVENT_RPC = 10,
    NETWORK_EVENT_RPC_RESP,
};

/* errcode and errstr are optional arguments, pass NULL to ignore them,
	errstr is filled by va() */
API int network_event(const char *msg, int *errcode, char **errstr);

enum { NETWORK_RANK = 0 }; // [0..N] where 0 is server
enum { NETWORK_PING = 1 }; // NETWORK_BANDWIDTH, NETWORK_QUALITY };
enum { NETWORK_PORT = 2, NETWORK_IP, NETWORK_LIVE };
enum { NETWORK_SEND_MS = 4 };
enum { NETWORK_BUF_CLEAR_ON_JOIN = 5 };
enum { NETWORK_USERID = 7, /*NETWORK_SALT,*/ NETWORK_COUNT/*N users*/ /*...*/, NETWORK_CAPACITY };
API int64_t network_get(uint64_t key);
API int64_t network_put(uint64_t key, int64_t value);

API void network_rpc(const char *signature, void *function);
API void network_rpc_send_to(int64_t rank, unsigned id, const char *cmdline);
API void network_rpc_send(unsigned id, const char *cmdline);

// -----------------------------------------------------------------------------
// low-level api (sockets based)

API bool   server_bind(int max_clients, int port);
API char** server_poll(unsigned timeout_ms);
API char** client_poll(unsigned timeout_ms);
API void   server_broadcast_bin_flags(const void *ptr, int len, uint64_t flags);
API void   server_broadcast_bin(const void *ptr, int len);
API void   server_broadcast_flags(const char *msg, uint64_t flags);
API void   server_broadcast(const char *msg);
API void   server_terminate();
API void   server_send(int64_t handle, const char *msg);
API void   server_send_bin(int64_t handle, const void *ptr, int len);
API void   server_drop(int64_t handle);

API int64_t  client_join(const char *ip, int port);
#define      client_send_flags(msg,flags) server_broadcast(msg, flags)
#define      client_send(msg) server_broadcast(msg)
#define      client_send_bin_flags(ptr,len,flags) server_broadcast_bin(ptr, len, flags)
#define      client_send_bin(ptr,len) server_broadcast_bin(ptr, len)
#define      client_terminate() server_terminate()

#define ANYHOST_IPV4 "0.0.0.0"
#define ANYHOST_IPV6 "::0"

#define LOCALHOST_IPV4 "127.0.0.1"
#define LOCALHOST_IPV6 "::1"
#line 0

#line 1 "v4k_obj.h"
// -----------------------------------------------------------------------------
// C object framework (constructors/destructors, methods, rtti, refcounting)
// - rlyeh, public domain.
//
// ## object api (low level)
//
// - [ ] make object from reflected type (factory)
// - [x] make object (if debug, include callstack as well)
// - [x] ctor method (optional, ref to constructor)
// - [x] dtor method (optional, ref to deleter)
// - [x] zero mem object
// - [x] object logger
// - [ ] iterate members in a struct
//
// - [x] clone/copy/mutate classes
// - [x] load/save objects from/to memory/disk
// - [ ] diff/patch objects
// - [ ] experimental: support for AoSoA layout (using objcnt, 3bits)
//
// ## object decomposition
//
//                             <---------|--------->
//            OBJ-SHADOW (64-bits)       |   OBJ CONTENT (N bytes)
// +-----+-----+-------------+-----------+-----+-----+-----+-----+--
// |TYPE |REFS.|   OBJ NAME  |  obj cnt  | ... | ... | ... | ... | .
// +-----+-----+-------------+-----------+-----+-----+-----+-----+--
// \-16-bits--/\---45-bits--/\--3-bits--/\-------N-bytes-----------
//
// OBJ TYPE+NAME format:
// - [type] custom tags at 0x0
// - [1..N] name
// - [\n]   blank separator
// - [comments, logger, infos, etc] << obj_printf();
//
// ## object limitations
// - 256 classes max
// - 256 references max
// - 8-byte overhead per object
// - 2 total allocs per object (could be flattened into 1 with some more work)
//
// @todo: obj_extend( "class_src", "class_dst" ); call[super(obj)]()
// @todo: preferred load/save format: [ver:1,user:2,type:1] ([eof|size:7/15/23/31][blob:N])+ [crc:1/2/3/4]
// @todo: more serious loading/saving spec

// object api (heap+rtti)

API void*       obj_malloc( int sz, ... );
API void*       obj_calloc( int sz, ... );
API void        obj_free( void *obj );

API bool        obj_typeeq( const void *obj1, const void *obj2 );
API const char* obj_typeof( const void *obj );
API unsigned    obj_typeid( const void *obj );
API unsigned    obj_typeid_from_name( const char *name );

// object api (ctor/dtor, refcounting, oop)

API void        obj_new( const char *type, ... );
API void        obj_del( void *obj );

API void*       obj_ref( void *obj );
API void*       obj_unref( void *obj );

API void        obj_extend( const char *dstclass, const char *srcclass );
API void        obj_override( const char *objclass, void (**vtable)(), void(*fn)() );

// object: serialize

API unsigned    obj_load(void *obj, const array(char) buffer);
API unsigned    obj_load_file(void *obj, FILE *fp);
API unsigned    obj_load_inplace(void *obj, const void *src, unsigned srclen);

API array(char) obj_save(const void *obj); // empty if error. must array_free() after use
API unsigned    obj_save_file(FILE *fp, const void *obj);
API unsigned    obj_save_inplace(void *dst, unsigned cap, const void *obj);

// object: utils

API unsigned    obj_instances( const void *obj );

API void        obj_zero( void *obj );
API unsigned    obj_sizeof( const void *obj );

API void        obj_hexdump( const void *obj );
API void        obj_hexdumpf( FILE *out, const void *obj );

API void        obj_printf( void *obj, const char *text );
API const char* obj_output( const void *obj );

API void *      obj_clone(const void *obj);
API void *      obj_copy(void **dst, const void *src);
API void *      obj_mutate(void **dst, const void *src);

// object: method dispatch tables

#define ctor(obj) obj_method0(obj, ctor) // ctor[obj_typeid(obj)](obj)
#define dtor(obj) obj_method0(obj, dtor) // dtor[obj_typeid(obj)](obj)

API extern void (*ctor[256])(); ///-
API extern void (*dtor[256])(); ///-

// object: syntax sugars

#define     obj_malloc(sz, ...) obj_initialize((void**)MALLOC(  sizeof(void*)+sz), stringf("\1untyped\n%s\n", "" #__VA_ARGS__))
#define     obj_calloc(sz, ...) obj_initialize((void**)CALLOC(1,sizeof(void*)+sz), stringf("\1untyped\n%s\n", "" #__VA_ARGS__))

#define     obj_new0(type) obj_new(type, 0)
#define     obj_new(type, ...) ( \
                obj_tmpalloc = obj_initialize((void**)CALLOC(1, sizeof(void*)+sizeof(type)), stringf("%c" #type "\n", (char)obj_typeid_from_name(#type))), \
                (*(type*)obj_tmpalloc = (type){ __VA_ARGS__ }), \
                ctor(obj_tmpalloc), \
                (type*)obj_tmpalloc )

#define     obj_override(class, method)    obj_override(#class, (void(**)())method, (void(*)())class##_##method)
#define     obj_method0(obj, method)       method[obj_typeid(obj)]((obj))
#define     obj_method(obj, method, ...)   method[obj_typeid(obj)]((obj), __VA_ARGS__)

#define     obj_printf(obj, ...)           obj_printf(obj, va(__VA_ARGS__))

#define     obj_extend(dstclass, srcclass) obj_extend(#dstclass, #srcclass)

// object: implementation details

// https://stackoverflow.com/questions/16198700/using-the-extra-16-bits-in-64-bit-pointers (note: using 19-bits here)
#define OBJBOX(ptr, payload16) (void*)(((long long unsigned)(payload16) << 48) | (long long unsigned)(ptr))
#define OBJUNBOX(ptr)          (void*)((long long unsigned)(ptr) & 0x0000FFFFFFFFFFFFull)
#define OBJPAYLOAD16(ptr)      (((long long unsigned)(ptr)) >> 48)
#define OBJPAYLOAD3(ptr)       (((long long unsigned)(ptr)) & 7)

API void* obj_initialize( void **ptr, char *type_and_info );
static __thread void *obj_tmpalloc;
#line 0

#line 1 "v4k_profile.h"
// -----------------------------------------------------------------------------
// profiler & stats (@fixme: threadsafe)

#if !ENABLE_PROFILER
#   define profile(section)             for(int macro(i) = 1; macro(i); macro(i) = 0)
#   define profile_incstat(name, accum) do {} while(0)
#   define profile_setstat(name, value) do {} while(0)
#   define profile_init()               do {} while(0)
#   define profile_render()             do {} while(0)
#   define profile_enable(x)            0
#else
#   define profile(section) for( \
        struct profile_t *found = profiler_enabled ? \
            map_find_or_add(profiler, section "@" FILELINE, (struct profile_t){NAN} ) : NULL, \
        *doit = found + ( found ? found->cost = -time_us(), 1 : 1 ); doit; \
        doit = found ? found->cost += time_us(), found->avg = found->cost * 0.25 + found->avg * 0.75, NULL : NULL)  ///+
#   define profile_incstat(name, accum) for( \
        struct profile_t *found = profiler_enabled ? map_find_or_add(profiler, name, (struct profile_t){0}) : NULL; \
        found; found->stat += accum, found = NULL) ///+
#   define profile_setstat(name, value) for( \
        struct profile_t *found = profiler_enabled ? map_find_or_add(profiler, name, (struct profile_t){0}) : NULL; \
        found; found->stat = value, found = NULL) ///+
API int profile_enable(bool on);

struct profile_t { double stat; int32_t cost, avg; }; ///-
typedef map(char *, struct profile_t) profiler_t; ///-
extern API profiler_t profiler; ///-
extern API int profiler_enabled; ///-
#endif
#line 0

#line 1 "v4k_render.h"
// -----------------------------------------------------------------------------
// naive rendering framework
// - rlyeh, public domain
//
// IQM skeletal meshes by @lsalzman (public domain) - https://bit.ly/2OQh0Me
// SH code by @ands (public domain) - https://github.com/ands/spherical_harmonics_playground
// SHM code by @jarikomppa (unlicensed) - https://github.com/jarikomppa/shadertoolkit

typedef unsigned handle; // GLuint

// -----------------------------------------------------------------------------
// colors

API unsigned rgba( uint8_t r, uint8_t g, uint8_t b, uint8_t a );
API unsigned bgra( uint8_t b, uint8_t g, uint8_t r, uint8_t a );
API unsigned rgbaf( float r, float g, float b, float a );
API unsigned bgraf( float b, float g, float r, float a );
API float    alpha( unsigned rgba );

#define RGBX(rgb,x)   ( ((rgb)&0xFFFFFF) | (((unsigned)(x))<<24) )
#define RGB3(r,g,b)   ( ((r)<<16) | ((g)<<8) | (b) )
#define RGB4(r,g,b,a) RGBX(RGB3(r,g,b),a)

#define BLACK   RGBX(0x000000,255)
#define WHITE   RGBX(0xFFF1E8,255)

#if 0
#define RED     RGBX(0xFF004D,255)
#define GREEN   RGBX(0x00B543,255)
#define BLUE    RGBX(0x065AB5,255)
#define ORANGE  RGBX(0xFF6C24,255)
#define CYAN    RGBX(0x29ADFF,255)
#define PURPLE  RGBX(0x7E2553,255)
#define YELLOW  RGBX(0xFFEC27,255)
#define GRAY    RGBX(0x725158,255)
#else
#define RED     RGB3(   255,48,48 )
#define GREEN   RGB3(  144,255,48 )
#define CYAN    RGB3(   0,192,255 )
#define ORANGE  RGB3(  255,144,48 )
#define PURPLE  RGB3(  102,77,102 ) // 178,128,255 )
#define YELLOW  RGB3(   255,224,0 )
#define GRAY    RGB3( 149,149,149 )
#define PINK    RGB3(  255,48,144 )
#define AQUA    RGB3(  48,255,144 )

#define BLUE    RGBX(0x065AB5,255)
#endif

// -----------------------------------------------------------------------------
// images

/// flags when constructing the image_t type. see: image, image_from_mem
/// IMAGE_R: 1-channel image (R)
/// IMAGE_RG: 2-channel image (R,G)
/// IMAGE_RGB: 3-channel image (R,G,B)
/// IMAGE_RGBA: 4-channel image (R,G,B,A)
/// IMAGE_FLIP: Flip image vertically
/// IMAGE_FLOAT: Float pixel components
enum IMAGE_FLAGS {
    IMAGE_R     = 0x01000,
    IMAGE_RG    = 0x02000,
    IMAGE_RGB   = 0x04000,
    IMAGE_RGBA  = 0x08000,
    IMAGE_FLIP  = 0x10000,
    IMAGE_FLOAT = 0x20000,
};

/// type that holds linear uncompressed bitmap of any given dimensions.
/// w,h: image dimensions in pixels. `x,y` alias.
/// comps: number of components per pixel. `n` alias.
/// pixels: untyped pointer to linear bitmap data. typed pointers use `pixels8/16/32/f` aliases.
/// see: texture_t
typedef struct image_t {
    union { unsigned x, w; };
    union { unsigned y, h; };
    union { unsigned n, comps; };
    union { void *pixels; uint8_t *pixels8; uint16_t *pixels16; uint32_t *pixels32; float *pixelsf; };
} image_t;

API image_t image(const char *pathfile, int flags);
API image_t image_from_mem(const void *ptr, int len, int flags);
API void    image_destroy(image_t *img);

// -----------------------------------------------------------------------------
// textures

enum TEXTURE_FLAGS {
    // UNIT[0..7]

    TEXTURE_BC1 = 8,  // DXT1, RGB with 8:1 compression ratio (+ optional 1bpp for alpha)
    TEXTURE_BC2 = 16, // DXT3, RGBA with 4:1 compression ratio (BC1 for RGB + 4bpp for alpha)
    TEXTURE_BC3 = 32, // DXT5, RGBA with 4:1 compression ratio (BC1 for RGB + BC4 for A)
//  TEXTURE_BC4,     // Alpha

    TEXTURE_NEAREST = 0,
    TEXTURE_LINEAR = 64,
    TEXTURE_MIPMAPS = 128,

    TEXTURE_CLAMP = 0,
    TEXTURE_BORDER = 0x100,
    TEXTURE_REPEAT = 0x200,

    TEXTURE_BYTE = 0,
    TEXTURE_FLOAT = IMAGE_FLOAT,

    TEXTURE_COLOR = 0,
    TEXTURE_DEPTH = 0x800,

    TEXTURE_R = IMAGE_R,
    TEXTURE_RG = IMAGE_RG,
    TEXTURE_RGB = IMAGE_RGB,
    TEXTURE_RGBA = IMAGE_RGBA,
    TEXTURE_FLIP = IMAGE_FLIP,

    // @fixme
    TEXTURE_SRGB = 1 << 24,
    TEXTURE_BGR = 1 << 25,
    TEXTURE_ARRAY = 1 << 26,
};

typedef struct texture_t {
    union { unsigned x, w; };
    union { unsigned y, h; };
    union { unsigned z, d; };
    union { unsigned n, bpp; };
    handle id, unit;
    unsigned texel_type;
    unsigned flags;
    char* filename;
    bool transparent;
    unsigned fbo; // for texture recording
} texture_t;

API texture_t texture_compressed(const char *filename, unsigned flags);
API texture_t texture_compressed_from_mem(const void *data, int len, unsigned flags);

API texture_t texture(const char* filename, int flags);
API texture_t texture_from_mem(const void* ptr, int len, int flags);
API texture_t texture_create(unsigned w, unsigned h, unsigned n, const void *pixels, int flags);
API texture_t texture_checker();
API void      texture_destroy(texture_t *t);
// textureLod(filename, dir, lod);
// void texture_add_loader( int(*loader)(const char *filename, int *w, int *h, int *bpp, int reqbpp, int flags) );
API unsigned  texture_update(texture_t *t, unsigned w, unsigned h, unsigned n, const void *pixels, int flags);

API bool      texture_rec_begin(texture_t *t, unsigned w, unsigned h); // texture_rec
API void      texture_rec_end(texture_t *t); // texture_rec

// -----------------------------------------------------------------------------
// brdf

API texture_t brdf_lut();

// -----------------------------------------------------------------------------
// pbr materials

typedef struct colormap_t {
    vec4 color;
    texture_t *texture;
} colormap_t;

API bool colormap( colormap_t *cm, const char *pbr_material_type, bool load_as_srgb );

typedef struct pbr_material_t {
    char* name;
    colormap_t diffuse;
    colormap_t normals;
    colormap_t specular;
    colormap_t albedo;
    colormap_t roughness;
    colormap_t metallic;
    colormap_t ao;
    colormap_t ambient;
    colormap_t emissive;

    float specular_shininess;
} pbr_material_t;

API bool pbr_material(pbr_material_t *pbr, const char *material);
API void pbr_material_destroy(pbr_material_t *m);

// -----------------------------------------------------------------------------
// fullscreen quads

API void  fullscreen_quad_rgb( texture_t texture_rgb, float gamma );
API void  fullscreen_quad_ycbcr( texture_t texture_YCbCr[3], float gamma );

// -----------------------------------------------------------------------------
// sprites

// texture id, position(x,y,depth sort), tint color, rotation angle
API void sprite( texture_t texture, float position[3], float rotation /*0*/, uint32_t color /*~0u*/);

// texture id, rect(x,y,w,h) is [0..1] normalized, z-index, pos(xy,scale), rotation (degrees), color (rgba)
API void sprite_rect( texture_t t, vec4 rect, float zindex, vec3 pos, float tilt_deg, unsigned tint_rgba);

// texture id, sheet(frameNumber,X,Y) (frame in a X*Y spritesheet), position(x,y,depth sort), rotation angle, offset(x,y), scale(x,y), is_additive, tint color
API void sprite_sheet( texture_t texture, float sheet[3], float position[3], float rotation, float offset[2], float scale[2], int is_additive, uint32_t rgba, int resolution_independant);

API void sprite_flush();

// -----------------------------------------------------------------------------
// tilemaps

typedef struct tileset_t {
    texture_t tex;            // spritesheet
    unsigned tile_w, tile_h;  // dimensions per tile in pixels
    unsigned cols, rows;      // tileset num_cols, num_rows
    unsigned selected;        // active tile (while editing)
} tileset_t;

API tileset_t tileset(texture_t tex, unsigned tile_w, unsigned tile_h, unsigned cols, unsigned rows);
API int       tileset_ui( tileset_t t );

typedef struct tilemap_t {
    int blank_chr;                // transparent tile
    unsigned cols, rows;          // map dimensions (in tiles)
    array(int) map;

    vec3 position;                // x,y,scale
    float zindex;
    float tilt;
    unsigned tint;
    bool is_additive;
} tilemap_t;

API tilemap_t tilemap(const char *map, int blank_chr, int linefeed_chr);
API void      tilemap_render( tilemap_t m, tileset_t style );
API void      tilemap_render_ext( tilemap_t m, tileset_t style, float zindex, float xy_zoom[3], float tilt, unsigned tint, bool is_additive );

// -----------------------------------------------------------------------------
// tiled maps

typedef struct tiled_t {
    char *map_name;
    unsigned first_gid, tilew, tileh, w, h;

    bool parallax;
    vec3 position;
    array(bool) visible;
    array(tilemap_t) layers;
    array(tileset_t) sets;
    array(char*) names;
} tiled_t;

API tiled_t tiled(const char *file_tmx);
API void    tiled_render(tiled_t tmx, vec3 pos);
API void    tiled_ui(tiled_t *t);

// -----------------------------------------------------------------------------
// spines

typedef struct spine_t spine_t;

API spine_t*spine(const char *file_json, const char *file_atlas, unsigned flags);
API void    spine_skin(spine_t *p, unsigned skin);
API void    spine_render(spine_t *p, vec3 offset, unsigned flags);
API void    spine_animate(spine_t *p, float delta);
API void    spine_ui(spine_t *p);

// -----------------------------------------------------------------------------
// cubemaps

typedef struct cubemap_t {
    unsigned id;    // texture id
    vec3 sh[9];     // precomputed spherical harmonics coefficients
} cubemap_t;

API cubemap_t  cubemap( const image_t image, int flags ); // 1 equirectangular panorama
API cubemap_t  cubemap6( const image_t images[6], int flags ); // 6 cubemap faces
API void       cubemap_destroy(cubemap_t *c);
API cubemap_t* cubemap_get_active();

// -----------------------------------------------------------------------------
// fbos

API unsigned fbo( unsigned texture_color, unsigned texture_depth, int wr_flags );
API void     fbo_bind(unsigned id);
API void     fbo_unbind();
API void     fbo_destroy(unsigned id);

// -----------------------------------------------------------------------------
// shadowmaps

// #ifndef VSMCUBE
// #define VSMCUBE 0
// #endif
// #ifndef VSMBLUR
// #define VSMBLUR 1
// #endif

typedef struct shadowmap_t {
    mat44  shadowmatrix;
    mat44  mvp;
    mat44  mv;
    mat44  proj;
    vec4   light_position;
    int    saved_fb;
    int    saved_viewport[4];
    handle fbo, texture;
    int texture_width;
} shadowmap_t;

API shadowmap_t shadowmap(int texture_width); // = 1024
API void shadowmap_destroy(shadowmap_t *s);

API void shadowmap_set_shadowmatrix(shadowmap_t *s, vec3 aLightPos, vec3 aLightAt, vec3 aLightUp, const mat44 projection);
API void shadowmap_begin(shadowmap_t *s);
API void shadowmap_end(shadowmap_t *s);

// shadowmap utils

API void shadowmatrix_proj(mat44 shm_proj, float aLightFov, float znear, float zfar);
API void shadowmatrix_ortho(mat44 shm_proj, float left, float right, float bottom, float top, float znear, float zfar);

// -----------------------------------------------------------------------------
// shaders

API unsigned shader(const char *vs, const char *fs, const char *attribs, const char *fragcolor);
API unsigned shader_geom(const char *gs, const char *vs, const char *fs, const char *attribs, const char *fragcolor);
API unsigned shader_bind(unsigned program);
API     void shader_bool(const char *uniform, bool i );
API     void shader_int(const char *uniform, int i);
API     void shader_uint(const char *uniform, unsigned i );
API     void shader_float(const char *uniform, float f);
API     void shader_vec2(const char *uniform, vec2 v);
API     void shader_vec3(const char *uniform, vec3 v);
API     void shader_vec3v(const char *uniform, int count, vec3 *v);
API     void shader_vec4(const char *uniform, vec4 v);
API     void shader_mat44(const char *uniform, mat44 m);
API     void shader_texture(const char *sampler, texture_t texture);
API     void shader_texture_unit(const char *sampler, unsigned texture, unsigned unit);
API     void shader_colormap(const char *name, colormap_t cm);
API unsigned shader_get_active();
API void     shader_destroy(unsigned shader);

// compute shaders
enum BUFFER_MODE {
    BUFFER_READ,
    BUFFER_WRITE,
    BUFFER_READ_WRITE
};

/// Loads the compute shader and compiles a GL program.
/// return: GL program, 0 if failed.
/// cs: shader source code
API unsigned compute(const char *cs);

/// Runs the compute program with provided global workgroup size on x y z grid.
/// wx: global workgroup size x
/// wy: global workgroup size y
/// wz: global workgroup size z
API void compute_dispatch(unsigned wx, unsigned wy, unsigned wz);

/// Binds a texture to the program
/// !!! Set `layer` to -1 to disable layered access.
/// t: texture to bind
/// unit: texture unit bind index
/// level: texture level access (MIP0, MIP1, ...)
/// layer: bind layer
/// access: texture access policy
/// see: BUFFER_MODE
API void shader_image(texture_t t, unsigned unit, unsigned level, int layer, unsigned access);

/// Binds a texture to the program
/// !!! Set `layer` to -1 to disable layered access.
/// texture: GL texture handle
/// unit: texture unit bind index
/// level: texture level access (MIP0, MIP1, ...)
/// layer: bind layer
/// texel_type: image texel format (RGBA8, RGBA32F, ...)
/// access: texture access policy
/// see: BUFFER_MODE
API void shader_image_unit(unsigned texture, unsigned unit, unsigned level, int layer, unsigned texel_type, unsigned access);

// gpu memory barriers

/// Blocks main thread until all image operations are done by the GPU.
API void image_write_barrier();

/// Blocks main thread until all memory operations are done by the GPU.
API void write_barrier();

// ssbo
/// `STATIC`, `DYNAMIC` AND `STREAM` specify the frequency at which we intend to access the data.
/// `DRAW` favors CPU->GPU operations.
/// `READ` favors GPU->CPU operations.
/// `COPY` favors CPU->GPU->CPU operations.
enum SSBO_USAGE {
    STATIC_DRAW,
    STATIC_READ,
    STATIC_COPY,

    DYNAMIC_DRAW,
    DYNAMIC_READ,
    DYNAMIC_COPY,

    STREAM_DRAW,
    STREAM_READ,
    STREAM_COPY
};

enum SSBO_ACCESS {
    SSBO_READ = BUFFER_READ,
    SSBO_WRITE = BUFFER_WRITE,
    SSBO_READ_WRITE = BUFFER_READ_WRITE
};

/// Create Shader Storage Buffer Object
/// !!! `data` can be NULL
/// data: optional pointer to data to upload
/// len: buffer size, must not be 0
/// usage: buffer usage policy
/// see: SSBO_USAGE
API unsigned ssbo_create(const void *data, int len, unsigned usage);

/// Destroys an SSBO resource
API void ssbo_destroy(unsigned ssbo);

/// Updates an existing SSBO
/// !!! `len` can not exceed the original buffer size specified in `ssbo_create` !
/// offset: offset to buffer memory
/// len: amount of data to write
/// data: pointer to data we aim to write, can not be NULL
API void ssbo_update(int offset, int len, const void *data);

/// Bind an SSBO resource to the provided bind unit index
/// ssbo: resource object
/// unit: bind unit index
API void ssbo_bind(unsigned ssbo, unsigned unit);

/// Map an SSBO resource to the system memory
/// !!! Make sure to `ssbo_unmap` the buffer once done working with it.
/// access: buffer access policy
/// return: pointer to physical memory of the buffer
/// see: SSBO_ACCESS
API void *ssbo_map(unsigned access);

/// Unmaps an SSBO resource
/// !!! Pointer provided by `ssbo_map` becomes invalid.
API void ssbo_unmap();

/// Unbinds an SSBO resource
API void ssbo_unbind();

// -----------------------------------------------------------------------------
// meshes (@fixme: deprecate?)

enum MESH_FLAGS {
    MESH_STATIC = 0, // STATIC, DYNAMIC, STREAM // zero|single|many updates per frame
    MESH_STREAM = 1,
    MESH_TRIANGLE_STRIP = 2,
};

typedef struct mesh_t {
    handle vao, vbo, ibo;
    unsigned vertex_count;
    unsigned index_count;
    unsigned flags;

	array(int) lod_collapse_map; // to which neighbor each vertex collapses. ie, [10] -> 7 (used by LODs) @leak

    // @leaks: following members are totally unused. convenient for end-users to keep their custom datas somewhere while processing.
    union {
	array(unsigned) in_index;
	array(vec3i)    in_index3;
    };
    union {
	array(unsigned) out_index;
	array(vec3i)    out_index3;
    };
	union {
    array(float) in_vertex;
    array(vec3) in_vertex3;
	};
	union {
    array(float) out_vertex;
    array(vec3) out_vertex3;
	};
} mesh_t;

API mesh_t mesh();
API   void mesh_update(mesh_t *m, const char *format, int vertex_stride,int vertex_count,const void *interleaved_vertex_data, int index_count,const void *index_data, int flags);
API   void mesh_render(mesh_t *m);
API   void mesh_render_prim(mesh_t *sm, unsigned prim);
API   void mesh_destroy(mesh_t *m);
API   aabb mesh_bounds(mesh_t *m);

// -----------------------------------------------------------------------------
// materials

enum MATERIAL_ENUMS {
    MAX_CHANNELS_PER_MATERIAL = 8
};

typedef struct material_t {
    char *name;

    int count;
    struct material_layer_t {
        char   texname[32];
        handle texture;
        float  value;
        vec4   color; // uint32_t
    } layer[MAX_CHANNELS_PER_MATERIAL];

} material_t;

// -----------------------------------------------------------------------------
// shadertoys

typedef struct shadertoy_t {
    handle vao, program;
    int uniforms[32];
    int texture_channels[4];
    int frame;
    float clickx, clicky;
    uint64_t t;
    texture_t tx;
    unsigned dims;
} shadertoy_t;

API shadertoy_t  shadertoy( const char *shaderfile, unsigned flags );
API shadertoy_t* shadertoy_render( shadertoy_t *s, float delta );

// -----------------------------------------------------------------------------
// anims

enum ANIM_FLAGS {
    ANIM_LOOP = 1,
    ANIM_DONT_RESET_AFTER_USE = 2,
};

typedef struct anim_t {
    int        from;
    int        to;
    float      blendtime;
    unsigned   flags;
    float      curframe;

    unsigned   easing;
    float      alpha; // refreshed at every tick
    float      timer; // private
    bool       active;

    vec3       pose; // private
    char*      name; // debug
} anim_t;

API anim_t clip(float minframe, float maxframe, float blendtime, unsigned flags);
API anim_t loop(float minframe, float maxframe, float blendtime, unsigned flags);
//API array(anim_t) animlist(const char *filename); // @todo

// -----------------------------------------------------------------------------
// models

enum MODEL_FLAGS {
    MODEL_NO_ANIMATIONS = 1,
    MODEL_NO_MESHES = 2,
    MODEL_NO_TEXTURES = 4,
    MODEL_MATCAPS = 8,
};

typedef struct model_t {
    struct iqm_t *iqm; // private

    unsigned num_textures;
    handle *textures;
    char **texture_names;
    array(material_t) materials;

    unsigned num_meshes;
    unsigned num_triangles;
    unsigned num_joints; // num_poses;
    unsigned num_anims;
    unsigned num_frames;
    handle program;
    float curframe;
    mat44 pivot;

    int stride; // usually 60 bytes (12*4+4*3) for a p3 u2 n3 t4 i4B w4B c4B vertex stream
    void *verts;
    int num_verts;
    handle vao, ibo, vbo, vao_instanced;

    unsigned flags;
    unsigned billboard;

    float *instanced_matrices;
    unsigned num_instances;
} model_t;

API model_t  model(const char *filename, int flags);
API model_t  model_from_mem(const void *mem, int sz, int flags);
API float    model_animate(model_t, float curframe);
API float    model_animate_clip(model_t, float curframe, int minframe, int maxframe, bool loop);
API float    model_animate_blends(model_t m, anim_t *primary, anim_t *secondary, float delta);
API aabb     model_aabb(model_t, mat44 transform);
API void     model_render(model_t, mat44 proj, mat44 view, mat44 model, int shader);
API void     model_render_skeleton(model_t, mat44 model);
API void     model_render_instanced(model_t, mat44 proj, mat44 view, mat44 *models, int shader, unsigned count);
API void     model_set_texture(model_t, texture_t t);
API bool     model_get_bone_pose(model_t m, unsigned joint, mat34 *out);
API void     model_destroy(model_t);

API vec3     pose(bool forward, float curframe, int minframe, int maxframe, bool loop, float *opt_retframe);

// -----------------------------------------------------------------------------
// model animations

typedef struct anims_t {
    int   inuse; // animation number in use
    float speed; // x1.00
    array(anim_t) anims; // [begin,end,flags] frames of every animation in set
} anims_t;

API anims_t animations(const char *pathfile, int flags);

// -----------------------------------------------------------------------------
// skyboxes

typedef struct skybox_t {
    handle program;
    mesh_t geometry;
    cubemap_t cubemap;
    int flags;

    // mie
    int framebuffers[6];
    int textures[6];
    float *pixels;
} skybox_t;

API skybox_t skybox(const char *panorama_or_cubemap_folder, int flags);
API int      skybox_render(skybox_t *sky, mat44 proj, mat44 view);
API void     skybox_destroy(skybox_t *sky);
API void     skybox_mie_calc_sh(skybox_t *sky, float sky_intensity);
API void     skybox_sh_reset(skybox_t *sky);
API void     skybox_sh_add_light(skybox_t *sky, vec3 light, vec3 dir, float strength);

API int      skybox_push_state(skybox_t *sky, mat44 proj, mat44 view); // @to deprecate
API int      skybox_pop_state(); // @to deprecate

// -----------------------------------------------------------------------------
// post-fxs

API void     viewport_color(uint32_t color); // background(uint32_t) instead?
API void     viewport_color3(vec3 color); // background3(vec3) instead?
API void     viewport_clear(bool color, bool depth);
API void     viewport_clip(vec2 from, vec2 to);

API int      fx_load(const char *file);
API int      fx_load_from_mem(const char *nameid, const char *content);
API void     fx_begin();
API void     fx_end();
API void     fx_enable(int pass, int enabled);
API int      fx_enabled(int pass);
API void     fx_enable_all(int enabled);
API char *   fx_name(int pass);
API int      fx_find(const char *name);

// -----------------------------------------------------------------------------
// utils

API void*    screenshot(int components); // 3 RGB, 4 RGBA, -3 BGR, -4 BGRA
API void*    screenshot_async(int components); // 3 RGB, 4 RGBA, -3 BGR, -4 BGRA
#line 0

#line 1 "v4k_renderdd.h"
// -----------------------------------------------------------------------------
// debugdraw framework
// - rlyeh, public domain.
//
// Credits: Based on work by @glampert https://github.com/glampert/debug-draw (PD)
// [x] grid, axis, frustum, cube, sphere, triangle, square, pentagon, hexagon, circle, normal.
// [x] arrow, point, text, capsule, aabb, plane, flotilla-style locator, boid, bone, ring
// [x] line batching
// [*] line width and stipple
// [*] (proper) gizmo,
// [ ] camera, light bulb, light probe,

API void ddraw_color(unsigned rgb);
API void ddraw_color_push(unsigned rgb);
API void ddraw_color_pop();
//
API void ddraw_ontop(int enabled);
API void ddraw_ontop_push(int enabled);
API void ddraw_ontop_pop();
//
API void ddraw_push_2d();
API void ddraw_pop_2d();
//
API void ddraw_aabb(vec3 minbb, vec3 maxbb);
API void ddraw_aabb_corners(vec3 minbb, vec3 maxbb);
API void ddraw_arrow(vec3 begin, vec3 end);
API void ddraw_axis(float units);
API void ddraw_boid(vec3 pos, vec3 dir);
API void ddraw_bone(vec3 center, vec3 end); // @todo: use me
API void ddraw_bounds(const vec3 points[8]);
API void ddraw_box(vec3 center, vec3 extents);
API void ddraw_capsule(vec3 from, vec3 to, float radius);
API void ddraw_circle(vec3 pos, vec3 n, float radius);
API void ddraw_ring(vec3 pos, vec3 n, float radius);
API void ddraw_cone(vec3 center, vec3 top, float radius);
API void ddraw_cube(vec3 center, float radius);
API void ddraw_cube33(vec3 center, vec3 radius, mat33 M);
API void ddraw_diamond(vec3 from, vec3 to, float size);
API void ddraw_frustum(float projview[16]);
API void ddraw_ground(float scale);
API void ddraw_grid(float scale);
API void ddraw_hexagon(vec3 pos, float radius);
API void ddraw_line(vec3 from, vec3 to);
API void ddraw_line_dashed(vec3 from, vec3 to);
API void ddraw_line_thin(vec3 from, vec3 to);
API void ddraw_normal(vec3 pos, vec3 n);
API void ddraw_pentagon(vec3 pos, float radius);
API void ddraw_plane(vec3 p, vec3 n, float scale);
API void ddraw_point(vec3 from);
API void ddraw_position(vec3 pos, float radius);
API void ddraw_position_dir(vec3 pos, vec3 dir, float radius);
API void ddraw_pyramid(vec3 center, float height, int segments);
API void ddraw_cylinder(vec3 center, float height, int segments);
API void ddraw_sphere(vec3 pos, float radius);
API void ddraw_square(vec3 pos, float radius);
API void ddraw_text(vec3 pos, float scale, const char *text);
API void ddraw_text2d(vec2 pos, const char *text);
API void ddraw_triangle(vec3 p1, vec3 p2, vec3 p3);
//
API void ddraw_prism(vec3 center, float radius, float height, vec3 normal, int segments);
//
API void ddraw_demo();
API void ddraw_flush();
API void ddraw_flush_projview(mat44 proj, mat44 view);
#line 0

#line 1 "v4k_scene.h"
// -----------------------------------------------------------------------------
// scene framework
// - rlyeh, public domain

// camera

typedef struct camera_t {
    mat44 view, proj;
    vec3 position, up, look; // position, updir, lookdir
    float yaw, pitch, speed; // mirror_x, mirror_y;
    vec3 last_look, last_move; // used for friction and smoothing
    float fov; // deg(45)
} camera_t;

API camera_t camera();
API void camera_teleport(camera_t *cam, vec3 pos);
API void camera_move(camera_t *cam, float incx, float incy, float incz);
API void camera_fov(camera_t *cam, float fov);
API void camera_fps(camera_t *cam, float yaw, float pitch);
API void camera_orbit(camera_t *cam, float yaw, float pitch, float inc_distance);
API void camera_lookat(camera_t *cam, vec3 target);
API void camera_enable(camera_t *cam);
API camera_t *camera_get_active();

// object

typedef struct object_t {
    uint64_t renderbucket;
    mat44 transform;
    quat rot;
    vec3 sca, pos, euler, pivot;
    array(handle) textures;
    model_t model;
    aabb bounds;
    unsigned billboard; // [0..7] x(4),y(2),z(1) masks
} object_t;

API object_t object();
API void object_rotate(object_t *obj, vec3 euler);
API void object_pivot(object_t *obj, vec3 euler);
API void object_teleport(object_t *obj, vec3 pos);
API void object_move(object_t *obj, vec3 inc);
API vec3 object_position(object_t *obj);
API void object_scale(object_t *obj, vec3 sca);
//
API void object_model(object_t *obj, model_t model);
API void object_diffuse(object_t *obj, texture_t tex);
API void object_diffuse_push(object_t *obj, texture_t tex);
API void object_diffuse_pop(object_t *obj);
API void object_billboard(object_t *obj, unsigned mode);

// object_pose(transform); // @todo

// scene

enum SCENE_FLAGS {
    SCENE_WIREFRAME = 1,
    SCENE_CULLFACE = 2,
    SCENE_BACKGROUND = 4,
    SCENE_FOREGROUND = 8,
};

typedef struct scene_t {
    handle program;

    array(object_t) objs;

    // special objects below:
    skybox_t skybox;
    int u_coefficients_sh;
} scene_t;

API scene_t*  scene_push();
API void      scene_pop();
API scene_t*  scene_get_active();

API int       scene_merge(const char *source);
API void      scene_render(int flags);

API object_t* scene_spawn();
API unsigned  scene_count();
API object_t* scene_index(unsigned index);
#line 0

#line 1 "v4k_script.h"
// -----------------------------------------------------------------------------
// script framework
// - rlyeh, public domain

API void script_init();
API void script_run(const char *script);
API void script_runfile(const char *pathfile);

API void script_bind_class(const char *objname, int num_methods, const char **c_names, void **c_functions);
API void script_bind_function(const char *c_name, void *c_function);
API void script_call(const char *lua_function);

API bool script_tests();
#line 0

#line 1 "v4k_string.h"
// string framework
// - rlyeh, public domain

// string: temporary api (stack)
API char*   tempvl(const char *fmt, va_list);
API char*   tempva(const char *fmt, ...);
#define     va(...) (((&printf) || printf(__VA_ARGS__), tempva(__VA_ARGS__)))  // vs2015 check trick

// string: allocated api (heap). FREE() after use
API char*   strcatf(char **s, const char *buf);
#define     strcatf(s,fmt,...)  strcatf((s), va(fmt, __VA_ARGS__))
#define     stringf(fmt,...)    STRDUP(va(fmt, __VA_ARGS__)) // (strcatf)(0, va(fmt, __VA_ARGS__))


#if is(cl) || (is(tcc) && is(win32))
#if!is(cl)
char* strtok_s(char* str,const char* delimiters,char** context); // tcc misses this in <string.h>
#endif
#define strtok_r strtok_s
#endif

#if 1
#define each_substring(str, delims, keyname) \
    ( int len_ = strlen(str) + 1; len_; len_ = 0 ) \
    for( char buf_[1024], *ptr_ = len_ < 1024 ? buf_ : REALLOC(0, len_), *lit_ = (char*)(str), *_bak = (snprintf(ptr_, len_, "%s", lit_), ptr_); _bak; _bak = 0, (ptr_ == buf_ ? 0 : REALLOC(ptr_, 0)) ) \
    for( char *next_token = 0, *keyname = strtok_r(_bak, delims, &next_token); keyname; keyname = strtok_r(NULL, delims, &next_token) )
#else
#define each_substring(str, delims, keyname) \
    ( char** tokens_ = strsplit((str), (delims)), *keyname = 0; tokens_; tokens_ = 0) \
    for( int i_ = 0, end_ = array_count(tokens_); i_ < (keyname = tokens_[i_], end_); ++i_ )
#endif

// utils

API int          strmatch(const char *s, const char *wildcard);
API int          strmatchi(const char *s, const char *wildcard);

API int          strcmp_qsort(const void *a, const void *b);
API int          strcmpi_qsort(const void *a, const void *b);

API bool         strbeg(const char *src, const char *sub); // returns true if both strings match at beginning. case sensitive
API bool         strend(const char *src, const char *sub); // returns true if both strings match at end. case sensitive

API bool         strbegi(const char *src, const char *sub);  // returns true if both strings match at beginning. case insensitive
API bool         strendi(const char *src, const char *sub);  // returns true if both strings match at end. case insensitive
API const char * strstri(const char *src, const char *sub);  // returns find first substring in string. case insensitive.
#define          strcmpi  ifdef(cl, _stricmp, strcasecmp)

API char *       strupper(const char *str);
API char *       strlower(const char *str);

API char *       strrepl(char **copy, const char *target, const char *replace); // replace any 'target' as 'repl' in 'copy'. 'copy' may change (heap). returns 'copy'
API char *       strswap(char *copy, const char *target, const char *replace);  // replaced inline only if repl is shorter than target. no allocations.
API char *       strcut(char *copy, const char *target);                        // remove any 'target' in 'copy'. returns 'copy'

API const char * strlerp(unsigned numpairs, const char **pairs, const char *str); // using key-value pairs, null-terminated

#ifndef __APPLE__ // BSD provides these
API size_t       strlcat(char *dst, const char *src, size_t dstcap); // concat 2 strings safely. always NUL terminates. may truncate.
API size_t       strlcpy(char *dst, const char *src, size_t dstcap); // copy 2 strings safely. always NUL terminates. truncates if retval>=dstcap
#endif

/// split `string` after any of `delimiters` character is found.
/// returns temporary array of split strings. see: strjoin
/// > array(char*) tokens = strsplit("hello! world!", " !"); // [0]="hello",[1]="world",
API array(char*)    strsplit(const char *string, const char *delimiters);

/// concatenate all elements within `list`, with `separator` string in between.
/// returns: temporary joint string. see: strsplit
/// > array(char*) tokens = strsplit("hello! world!", " !"); // [0]="hello",[1]="world",
/// > char *joint = strjoin(tokens, "+"); // joint="hello+world"
API char*           strjoin(array(char*) list, const char *separator);

API char *          string8(const wchar_t *str);  /// convert from wchar16(win) to utf8/ascii
API array(uint32_t) string32( const char *utf8 ); /// convert from utf8 to utf32
#line 0

#line 1 "v4k_system.h"
// -----------------------------------------------------------------------------
// system framework utils
// - rlyeh, public domain.
//
// Note: Windows users add `/Zi` compilation flags, else add `-g` and/or `-ldl` flags
// Note: If you are linking your binary using GNU ld you need to add --export-dynamic

API void*       thread( int (*thread_func)(void* user_data), void* user_data );
API void        thread_destroy( void *thd );

API int         argc();
API char*       argv(int);

API int         flag(const char *commalist); // --arg // app_flag?
API const char* option(const char *commalist, const char *defaults); // --arg=value or --arg value
API int         optioni(const char *commalist, int defaults); // argvi() ?
API float       optionf(const char *commalist, float defaults); // app_option?

API void        tty_color(unsigned color);
API void        tty_reset();
API void        tty_attach();
API void        tty_detach();

API const char* app_exec(const char *command); // returns ("%15d %s", retcode, output_last_line)
API int         app_cores();
API int         app_battery(); /// return battery level [1..100]. also positive if charging (+), negative if discharging (-), and 0 if no battery is present.

API const char* app_name();
API const char* app_path();
API const char* app_cache();
API const char* app_temp();
API const char* app_cmdline();

API uint64_t    date();        // YYYYMMDDhhmmss
API uint64_t    date_epoch();  // linux epoch
API char*       date_string(); // "YYYY-MM-DD hh:mm:ss"
API double      time_hh();
API double      time_mm();
API double      time_ss();
API uint64_t    time_ms();
API uint64_t    time_us();
API uint64_t    time_ns();
API void        sleep_ss(double ss);
API void        sleep_ms(double ms);
API void        sleep_us(double us);
API void        sleep_ns(double us);

API unsigned    timer(unsigned ms, unsigned (*callback)(unsigned ms, void *arg), void *arg);
API void        timer_destroy(unsigned timer_handle);

API char*       callstack( int traces ); // write callstack into a temporary string. <0 traces to invert order. do not free().
API int         callstackf( FILE *fp, int traces ); // write callstack to file. <0 traces to invert order.

API void        die(const char *message);
API void        alert(const char *message);
API void        hexdump( const void *ptr, unsigned len );
API void        hexdumpf( FILE *fp, const void *ptr, unsigned len, int width );
API void        breakpoint(const char *optional_reason);
API bool        has_debugger();

API void        signal_hooks(void);
API void        signal_handler_ignore(int signal);
API void        signal_handler_quit(int signal);
API void        signal_handler_abort(int signal);
API void        signal_handler_debug(int signal);
API const char *signal_name(int signal); // helper util

API uint16_t    lil16(uint16_t n); // swap16 as lil
API uint32_t    lil32(uint32_t n); // swap32 as lil
API float       lil32f(float n);   // swap32 as lil
API uint64_t    lil64(uint64_t n); // swap64 as lil
API double      lil64f(double n);  // swap64 as lil
API uint16_t    big16(uint16_t n); // swap16 as big
API uint32_t    big32(uint32_t n); // swap32 as big
API float       big32f(float n);   // swap32 as big
API uint64_t    big64(uint64_t n); // swap64 as big
API double      big64f(double n);  // swap64 as big

API uint16_t*   lil16p(void *n, int sz);
API uint32_t*   lil32p(void *n, int sz);
API float*      lil32pf(void *n, int sz);
API uint64_t*   lil64p(void *n, int sz);
API double*     lil64pf(void *n, int sz);
API uint16_t*   big16p(void *n, int sz);
API uint32_t*   big32p(void *n, int sz);
API float*      big32pf(void *n, int sz);
API uint64_t*   big64p(void *n, int sz);
API double*     big64pf(void *n, int sz);

#define PANIC(...)   PANIC(va(__VA_ARGS__), __FILE__, __LINE__) // die() ?
API int (PANIC)(const char *error, const char *file, int line);

#define PRINTF(...)  PRINTF(va(__VA_ARGS__), 1[#__VA_ARGS__] == '!' ? callstack(+48) : "", __FILE__, __LINE__, __FUNCTION__)
API int (PRINTF)(const char *text, const char *stack, const char *file, int line, const char *function);
#line 0

#line 1 "v4k_ui.h"
// -----------------------------------------------------------------------------
// immediate ui framework
// - rlyeh, public domain
//
// @todo: logger/console
// @todo: surround-adaptive window resizing. ie, surrounding windows adapting theirselves to fit dragged active window

enum PANEL_FLAGS {
    PANEL_OPEN = 1,
};

API int ui_notify(const char *title, const char *body);
API int ui_window(const char *title, int *enabled);
API int  ui_panel(const char *title, int flags); // may be embedded inside a window, or standalone
API int   ui_collapse(const char *label, const char *id);
API int   ui_contextual();
API int    ui_section(const char *title);
API int    ui_int(const char *label, int *value);
API int    ui_bool(const char *label, bool *value);
API int    ui_short(const char *label, short *value);
API int    ui_float(const char *label, float *value);
API int    ui_float2(const char *label, float value[2]);
API int    ui_float3(const char *label, float value[3]);
API int    ui_float4(const char *label, float value[4]);
API int    ui_double(const char *label, double *value);
API int    ui_buffer(const char *label, char *buffer, int buflen);
API int    ui_string(const char *label, char **string);
API int    ui_color3(const char *label, float *color3); //[0..255]
API int    ui_color3f(const char *label, float *color3); //[0..1]
API int    ui_color4(const char *label, float *color4); //[0..255]
API int    ui_color4f(const char *label, float *color4); //[0..1]
API int    ui_unsigned(const char *label, unsigned *value);
API int    ui_button(const char *label);
API int    ui_button_transparent(const char *label);
API int    ui_buttons(int buttons, /*labels*/...);
API int    ui_toolbar(const char *options); // int choice = ui_toolbar("A;B;C;D");
API int    ui_submenu(const char *options); // int choice = ui_submenu("A;B;C;D");
API int    ui_browse(const char **outfile, bool *inlined); // may be embedded inside a window or inside a panel
API int    ui_toggle(const char *label, bool *value);
API int    ui_dialog(const char *title, const char *text, int choices, bool *show); // @fixme: return
API int    ui_list(const char *label, const char **items, int num_items, int *selector);
API int    ui_radio(const char *label, const char **items, int num_items, int *selector);
API int    ui_texture(const char *label, texture_t t);
API int    ui_subtexture(const char *label, texture_t t, unsigned x, unsigned y, unsigned w, unsigned h);
API int    ui_image(const char *label, handle id, unsigned w, unsigned h); //(w,h) can be 0
API int    ui_subimage(const char *label, handle id, unsigned iw, unsigned ih, unsigned sx, unsigned sy, unsigned sw, unsigned sh);
API int    ui_colormap(const char *label, colormap_t *cm); // returns num member changed: 1 for color, 2 for texture map
API int    ui_separator();
API int    ui_bits8(const char *label, uint8_t *bits);
API int    ui_bits16(const char *label, uint16_t *bits);
API int    ui_console();
API int    ui_clampf(const char *label, float *value, float minf, float maxf);
API int    ui_label(const char *label);
API int    ui_label2(const char *label, const char *caption);
API int    ui_label2_toolbar(const char *label, const char *icons);
API int    ui_slider(const char *label, float *value);
API int    ui_slider2(const char *label, float *value, const char *caption);
API int    ui_const_bool(const char *label, const double value);
API int    ui_const_float(const char *label, const double value);
API int    ui_const_string(const char *label, const char *value);
API int   ui_contextual_end();
API int   ui_collapse_clicked();
API int   ui_collapse_end();
API int  ui_panel_end();
API int ui_window_end();

API int ui_show(const char *panel_or_window_title, int enabled);
API int ui_visible(const char *panel_or_window_title); // @todo: include ui_collapse() items that are open as well?
API int ui_enable();
API int ui_disable();

API int ui_has_menubar();
API int ui_menu(const char *items); // semicolon-separated or comma-separated items
API int ui_menu_editbox(char *buf, int bufcap);
API int ui_item();

API int ui_popups(); // ui_any_popup()? ui_has_popups()?
API int ui_hover(); // ui_is_hover()?
API int ui_active(); // ui_is_active()?

API int ui_demo(int do_windows);
#line 0

#line 1 "v4k_video.h"
// -----------------------------------------------------------------------------
// video decoder (mpeg)
// - rlyeh, public domain
//
// [ref] https://github.com/phoboslab/pl_mpeg/blob/master/pl_mpeg_player.c
// [use] ffmpeg -i infile.mp4 -c:v mpeg1video -c:a mp2 -format mpeg outfile.mpg

enum VIDEO_FLAGS {
    VIDEO_YCBCR = 0,
    VIDEO_RGB = 1,

    VIDEO_AUDIO = 0,
    VIDEO_NO_AUDIO = 2,
};

typedef struct video_t video_t;

API video_t*   video( const char *filename, int flags );
API texture_t*  video_decode( video_t *v ); // decodes next frame, returns associated texture(s)
API texture_t*  video_textures( video_t *v ); // returns last video textures. does not perform any decoding.
API int         video_has_finished(video_t *v);
API double      video_duration(video_t *v);
API int         video_seek(video_t *v, double seek_to);
API double      video_position(video_t *v);
API void        video_pause(video_t *v, bool paused);
API bool        video_is_paused(video_t *v);
API bool        video_is_rgb(video_t *v);
API void       video_destroy( video_t *v );

// -----------------------------------------------------------------------------
// video recorder (uses external ffmpeg and fallbacks to built-in mpeg1 encoder)
// - rlyeh, public domain
//
// @fixme: MSAA can cause some artifacts with Intel PBOs: either use glDisable(GL_MULTISAMPLE) before recording or do not create window with WINDOW_MSAA at all.

API bool       record_start(const char *outfile_mp4);
API bool        record_active();
API void       record_stop(void);
#line 0

#line 1 "v4k_window.h"
// -----------------------------------------------------------------------------
// window framework
// - rlyeh, public domain
//
// @todo: window_cursor(ico);
// @todo: if WINDOW_PORTRAIT && exist portrait monitor, use that instead of primary one
// @todo: WINDOW_TRAY

enum WINDOW_FLAGS {
    WINDOW_MSAA2 = 0x02,
    WINDOW_MSAA4 = 0x04,
    WINDOW_MSAA8 = 0x08,

    WINDOW_SQUARE = 0x20,
    WINDOW_PORTRAIT = 0x40,
    WINDOW_LANDSCAPE = 0x80,
    WINDOW_ASPECT = 0x100, // keep aspect
    WINDOW_FIXED = 0x200, // disable resizing

    WINDOW_VSYNC = 0,
    WINDOW_VSYNC_ADAPTIVE = 0x1000,
    WINDOW_VSYNC_DISABLED = 0x2000,
};

API bool     window_create(float scale, unsigned flags);
API bool     window_create_from_handle(void *handle, float scale, unsigned flags);
API void     window_reload();

API int      window_frame_begin();
API void     window_frame_end();
API void     window_frame_swap();
API int      window_swap(); // single function that combines above functions (desktop only)

API void     window_loop(void (*function)(void* loopArg), void* loopArg ); // run main loop function continuously (emscripten only)
API void     window_loop_exit(); // exit from main loop function (emscripten only)

API void     window_title(const char *title);
API void     window_icon(const char *file_icon);
API void     window_color(unsigned color);
API vec2     window_canvas();
API void*    window_handle();
API char*    window_stats();

API uint64_t window_frame();
API int      window_width();
API int      window_height();
API double   window_time();
API double   window_delta();

// API bool  window_hook(void (*func)(), void* userdata); // deprecated
// API void  window_unhook(void (*func)()); // deprecated

API void     window_focus(); // window attribute api using haz catz language for now
API int      window_has_focus();
API void     window_fullscreen(int enabled);
API int      window_has_fullscreen();
API void     window_cursor(int visible);
API int      window_has_cursor();
API void     window_pause(int paused);
API int      window_has_pause();
API void     window_visible(int visible);
API int      window_has_visible();

API double   window_aspect();
API void     window_aspect_lock(unsigned numer, unsigned denom);
API void     window_aspect_unlock();

API double   window_fps();
API double   window_fps_target();
API void     window_fps_lock(float fps);
API void     window_fps_unlock();

API void     window_screenshot(const char* outfile_png); // , bool record_cursor
API int      window_record(const char *outfile_mp4); // , bool record_cursor

enum CURSOR_SHAPES {
    CURSOR_NONE,
    CURSOR_HW_ARROW,  // default
    CURSOR_HW_IBEAM,  // i-beam text cursor
    CURSOR_HW_CROSS,  // crosshair
    CURSOR_HW_HAND,   // hand, clickable
    CURSOR_HW_HDRAG,  // horizontal drag/resize
    CURSOR_HW_VDRAG,  // vertical drag/resize
    CURSOR_SW_AUTO,   // software cursor, ui driven. note: this is the only icon that may be recorded or snapshotted
};

API void     window_cursor_shape(unsigned shape);
#line 0

// ----

#if is(cpp)
} // extern "C"
#endif

// expose glfw/glad apis
#if is(ems)
    #include <GL/glew.h>
    #include <GLFW/glfw3.h>
    #include <emscripten.h>
    #include <emscripten/html5.h>
    #define gladLoadGL(func) (glewExperimental = true, glewInit() == GLEW_OK)
#else
    #if is(win32) /*&& is(tcc)*/ // && WITH_DLL
    #ifdef GLAD_API_CALL
    #undef GLAD_API_CALL
    #endif
    #define GLAD_API_CALL extern API
    #endif
    #ifndef GLAD_GL_H_
    #include "v4k"
    #endif
#endif

#endif // V4K_H