Test compare shader (not working D:)

compare.glsl

@@ -0,0 +1,19 @@
+// Compute the pixelwise diff between two textures.
+// Computes the diff for each color chanel separately (r, g, b).
+// Assumes both images are not transparent.
+
+// try isampler2D, ivec4 etc.? Probably not
+uniform vec2 size;
+uniform sampler2D base;
+uniform sampler2D curr;
+
+void main(void)
+{
+	vec2 pos = gl_FragCoord.xy/size;
+// 	vec4 color = texture(curr, pos);  // fails for some reason!?
+// 	vec4 basecolor = texture(base, pos);  // fails too...
+// 	color.xyz = abs(color.xyz - basecolor.xyz);
+// 	gl_FragColor = color;
+// 	gl_FragColor = basecolor;
+	gl_FragColor = vec4(1.0);
+}