randomly translate noise every frame

shader/root/rt.glsl

@@ -26,7 +26,6 @@ layout (location = 13)  uniform Sphere _spheres[SPHERES];
 
 uniform vec4 _seed;
 
-
 layout(rgba32f, binding = 0) uniform image2D img_output;        // rgba32f defines internal format, image2d for random write to output texture
 layout(binding=1) uniform sampler2D _noise;                     // noise texture
 
@@ -164,7 +163,10 @@ vec2 pixelUv()
 
 vec4 sampleNoise()
 {
-    return texture(_noise, pixelUv());
+    vec2 uv = pixelUv();
+    uv += _seed.xy;
+
+    return texture(_noise, uv);
 }
 
 float random(vec2 st)
@@ -242,8 +244,8 @@ void main()
 
     vec2 uv = pixelUv();
 
-    int samples = 2;
-    int bounces = 2;
+    int samples = 1;
+    int bounces = 4;
 
     for (int i = 0; i < samples; i++) 
     {

src/main.c

@@ -13,17 +13,15 @@ void updateUniforms(GLuint shaderProgram);
 
 int main()
 {
+    printf("GL_TEXTURE0: %d\n", GL_TEXTURE0);
+    printf("GL_TEXTURE1: %d\n", GL_TEXTURE1);
+
     randomInit();
 
     // create a window and opengl context
     SDL_Window* window = gfxInit(WIDTH, HEIGHT);
 
-    // generate noise
-    GLuint noise = createNoiseTexture(WIDTH, HEIGHT);
 
-    // create a texture for the compute shader to write to
-    GLuint textureOutput = createWriteOnlyTexture(WIDTH, HEIGHT);
-    printWorkGroupLimits();
 
     // compile shader programs
     unsigned int computeProgram = compileComputeShaderProgram(
@@ -32,10 +30,16 @@ int main()
             "bin/shader.vert", 
             "bin/shader.frag");
 
+    // generate noise
+    GLuint noise = createNoiseTexture(WIDTH, HEIGHT);
     glBindTexture(GL_TEXTURE_2D, noise);
     int noiseLoc = glGetUniformLocation(computeProgram, "_noise");
     glUniform1i(noiseLoc, noise);
 
+    // create a texture for the compute shader to write to
+    GLuint textureOutput = createWriteOnlyTexture(WIDTH, HEIGHT);
+    printWorkGroupLimits();
+
     // initialise quad
     initBuffers();
     setVertexAttributes();

todo.md

@@ -1,3 +1,6 @@
+* [-] preprocessor
+    * [x] #include directives
+    * [ ] keep track of previously included files to avoid redefinitions
 * [-] render image with compute shader
     * [x] render a texture to a full-screen quad
     * [x] pass uniforms to shader to animate it