add MODEL_PBR flag

bind/v4k.lua

@@ -1333,6 +1333,7 @@ enum MODEL_FLAGS {
     MODEL_NO_FILTERING = 8,
     MODEL_MATCAPS = 16,
     MODEL_RIMLIGHT = 32,
+    MODEL_PBR = 64,
 };
 enum SHADING_MODE {
     SHADING_NONE,

demos/06-material.c

@@ -20,8 +20,7 @@ int main() {
     // load model
     model_t m1 = model("suzanne.obj", MODEL_NO_ANIMATIONS);
     model_t m2 = model("suzanne.obj", MODEL_NO_ANIMATIONS|MODEL_MATCAPS);
-    model_t m3 = model("damagedhelmet.gltf", MODEL_NO_ANIMATIONS);
-    model_shading(&m3, SHADING_PBR);
+    model_t m3 = model("damagedhelmet.gltf", MODEL_NO_ANIMATIONS|MODEL_PBR);
 
     // spawn object1 (diffuse)
     object_t* obj1 = scene_spawn();

engine/joint/v4k.h

@@ -17563,6 +17563,7 @@ enum MODEL_FLAGS {
     MODEL_NO_FILTERING = 8,
     MODEL_MATCAPS = 16,
     MODEL_RIMLIGHT = 32,
+    MODEL_PBR = 64,
 };
 
 enum SHADING_MODE {
@@ -373565,6 +373566,9 @@ model_t model_from_mem(const void *mem, int len, int flags) {
 
         glGenBuffers(1, &m.vao_instanced);
         model_set_state(m);
+        if (flags & MODEL_PBR) {
+            model_shading(&m, SHADING_PBR);
+        }
     }
     return m;
 }

engine/split/v4k_render.c

@@ -3538,6 +3538,9 @@ model_t model_from_mem(const void *mem, int len, int flags) {
 
         glGenBuffers(1, &m.vao_instanced);
         model_set_state(m);
+        if (flags & MODEL_PBR) {
+            model_shading(&m, SHADING_PBR);
+        }
     }
     return m;
 }

engine/split/v4k_render.h

@@ -541,6 +541,7 @@ enum MODEL_FLAGS {
     MODEL_NO_FILTERING = 8,
     MODEL_MATCAPS = 16,
     MODEL_RIMLIGHT = 32,
+    MODEL_PBR = 64,
 };
 
 enum SHADING_MODE {

engine/v4k.c

@@ -20712,6 +20712,9 @@ model_t model_from_mem(const void *mem, int len, int flags) {
 
         glGenBuffers(1, &m.vao_instanced);
         model_set_state(m);
+        if (flags & MODEL_PBR) {
+            model_shading(&m, SHADING_PBR);
+        }
     }
     return m;
 }

engine/v4k.h

@@ -3630,6 +3630,7 @@ enum MODEL_FLAGS {
     MODEL_NO_FILTERING = 8,
     MODEL_MATCAPS = 16,
     MODEL_RIMLIGHT = 32,
+    MODEL_PBR = 64,
 };
 
 enum SHADING_MODE {