in vec2 position;
out vec2 image_pos;
flat out vec2 flow_du;
+flat out float mean_diff;
uniform int width_patches;
uniform vec2 patch_size; // In 0..1 coordinates.
image_pos = patch_spacing * ivec2(patch_x, patch_y) + patch_size * grown_pos;
// Find the flow value for this patch, and send it on to the fragment shader.
- flow_du = texelFetch(flow_tex, ivec2(patch_x, patch_y), 0).xy;
+ vec3 flow_du_and_mean_diff = texelFetch(flow_tex, ivec2(patch_x, patch_y), 0).xyz;
+ flow_du = flow_du_and_mean_diff.xy;
+ mean_diff = flow_du_and_mean_diff.z;
// The result of glOrtho(0.0, 1.0, 0.0, 1.0, 0.0, 1.0) is:
//