v4k-git-backup/engine/art/shaders/shadowmap.glsl

112 lines
4.3 KiB
GLSL

// uniform mat4 view = mat4(1.0);
uniform vec3 lightPos; /// set:1,1,1
uniform float doTexture; /// set:1
#ifdef VSMCUBE
uniform samplerCube shadowMap; // VSMCUBE
#else
uniform sampler2D shadowMap; // !VSMCUBE
#endif
struct light {
vec3 position; // world-space
vec4 diffuse;
vec4 specular;
float constantAttenuation, linearAttenuation, quadraticAttenuation;
};
light light0 = light(
vec3(1,1,1), // lightPos
vec4(1,1,1,1), // diffuse
vec4(1,1,1,1), // specular
1.0, 0.0, 0.0 // attenuation (const, linear, quad)
);
// From http://fabiensanglard.net/shadowmappingVSM/index.php
#ifdef VSMCUBE
float chebyshevUpperBound(float distance, vec3 dir) {
distance = distance/20 ;
vec2 moments = texture(shadowMap, dir).rg;
#else
float chebyshevUpperBound(float distance, vec4 scPostW) {
vec2 moments = texture(shadowMap,scPostW.xy).rg;
#endif
// Surface is fully lit. as the current fragment is before the light occluder
if (distance <= moments.x)
return 1.0;
// The fragment is either in shadow or penumbra. We now use chebyshev's upperBound to check
// How likely this pixel is to be lit (p_max)
float variance = moments.y - (moments.x*moments.x);
//variance = max(variance, 0.000002);
variance = max(variance, 0.00002);
float d = distance - moments.x;
float p_max = variance / (variance + d*d);
return p_max;
}
vec4 shadowmap(in vec4 vpeye, in vec4 vneye, in vec2 uv, in vec4 sc) {
#ifndef VSMCUBE
return vec4(1.);
#else
vec3 fragment = vec3(vpeye);
vec3 normal = vec3(normalize(vneye));
vec3 viewDir = normalize(-fragment);
// Lighting
// Convert to eye-space
vec3 light = vec3(view * vec4(light0.position, 1.0));
#ifdef VSMCUBE
// Vectors
vec3 fragmentToLight = light - fragment;
vec3 fragmentToLightDir = normalize(fragmentToLight);
// Shadows
vec4 fragmentToLight_world = inverse(view) * vec4(fragmentToLightDir, 0.0);
float shadowFactor = chebyshevUpperBound(length(fragmentToLight), -fragmentToLight_world.xyz);
#else
// Shadows
vec4 scPostW = sc / sc.w;
scPostW = scPostW * 0.5 + 0.5;
float shadowFactor = 1.0; // Not in shadow
bool outsideShadowMap = sc.w <= 0.0f || (scPostW.x < 0 || scPostW.y < 0) || (scPostW.x >= 1 || scPostW.y >= 1);
if (!outsideShadowMap) {
shadowFactor = chebyshevUpperBound(scPostW.z, scPostW);
}
#endif
vec4 diffColor = vec4(1,1,1,1);
#ifdef VSMCUBE
if(doTexture != 0) diffColor = vec4(vec3(texture(shadowMap, -fragmentToLight_world.xyz).r), 1.0);
#else
if(doTexture != 0) diffColor = vec4(vec3(texture(shadowMap, vec2(uv.x, 1.0 - uv.y)).r), 1.0);
#endif
#if 1
vec3 positionToLight = light - fragment;
vec3 lightDir = normalize(positionToLight);
// Angle between fragment-normal and incoming light
float cosAngIncidence = dot(lightDir, normal);
cosAngIncidence = clamp(cosAngIncidence, 0, 1);
float attenuation = 1.0f;
attenuation = 1.0 / (light0.constantAttenuation + light0.linearAttenuation * length(positionToLight) + light0.quadraticAttenuation * pow(length(positionToLight),2));
vec4 diffuse = diffColor * light0.diffuse * cosAngIncidence * attenuation;
vec4 total_lighting;
total_lighting += vec4(0.1, 0.1, 0.1, 1.0) * diffColor; // Ambient
total_lighting += diffuse * shadowFactor; // Diffuse
#else
vec4 total_lighting = diffColor;
#endif
return vec4(clamp(vec3(total_lighting), 0., 1.), 1.0);
#endif
}