Uniforms and compiling shaders with a script

src/shaders/triangle.glsl

@@ -11,11 +11,15 @@ void main() {
 @end
 
 @fs fs
+uniform fs_params {
+    vec3 offset;
+};
+
 in vec4 color;
 out vec4 frag_color;
 
 void main() {
-    frag_color = color;
+    frag_color = color * offset.r;
 }
 @end