Vulkan port

assets/shaders.glsl

@@ -1,4 +1,4 @@
-@vs vertex
+@vs vs_main
 
 layout(location = 0) in vec3 positionOS;
 layout(location = 1) in vec2 texCoord;
@@ -43,7 +43,7 @@ void main() {
 }
 @end
 
-@fs fragment
+@fs fs_main
 
 struct Point_Light {
     vec3 positionWS;
@@ -217,4 +217,60 @@ void main() {
 
 @end
 
-@program main vertex fragment
+@cs cs_equirectangular_to_cubemap
+
+layout(binding = 0) uniform Layer_Index {
+    int _LayerIndex;
+};
+
+layout(binding = 0) uniform texture2D _EquirectangularTexture;
+layout(binding = 1, rgba16f) uniform writeonly image2DArray _CubemapImage;
+
+layout(binding = 0) uniform sampler _EquirectangularSampler;
+
+const float INV_PI = 0.31830987;
+const float HALF_INV_PI = 0.15915494;
+
+layout(local_size_x = 8, local_size_y = 8) in;
+void main() {
+    vec2 size = vec2(imageSize(_CubemapImage).xy);
+    vec2 texCoord = (vec2(gl_GlobalInvocationID.xy) + vec2(0.5)) / size;
+
+    texCoord = texCoord * vec2(2.0) - vec2(1.0); // Map to range [-1, 1]
+
+    vec3 cubeCoord;
+    if (_LayerIndex == 0) {
+        // Positive X
+        cubeCoord = vec3(1, -texCoord.y, -texCoord.x);
+    } else if (_LayerIndex == 1) {
+        // Negative X
+        cubeCoord = vec3(-1, -texCoord.y, texCoord.x);
+    } else if (_LayerIndex == 2) {
+        // Positive Y
+        cubeCoord = vec3(texCoord.x, 1, texCoord.y);
+    } else if (_LayerIndex == 3) {
+        // Negative Y
+        cubeCoord = vec3(texCoord.x, -1, -texCoord.y);
+    } else if (_LayerIndex == 4) {
+        // Positive Z
+        cubeCoord = vec3(texCoord.x, -texCoord.y, 1);
+    } else if (_LayerIndex == 5) {
+        // Negative Z
+        cubeCoord = vec3(-texCoord.x, -texCoord.y, -1);
+    }
+
+    vec3 cubeDir = normalize(cubeCoord);
+
+    float theta = atan(cubeDir.y, cubeDir.x);
+    float phi = asin(cubeDir.z);
+
+    vec2 equirectCoord = vec2(theta * HALF_INV_PI, phi * INV_PI) + vec2(0.5);
+
+    vec4 irradiance = texture(sampler2D(_EquirectangularTexture, _EquirectangularSampler), equirectCoord);
+    imageStore(_CubemapImage, ivec3(ivec2(gl_GlobalInvocationID.xy), _LayerIndex), irradiance);
+}
+
+@end
+
+@program main vs_main fs_main
+@program equirectangular_to_cubemap cs_equirectangular_to_cubemap