flat out vec2 flow_du;
flat out float mean_diff;
-uniform int width_patches;
uniform vec2 patch_size; // In 0..1 coordinates.
uniform vec2 patch_spacing; // In 0..1 coordinates.
uniform sampler2D flow_tex;
void main()
{
- int patch_x = gl_InstanceID % width_patches;
- int patch_y = gl_InstanceID / width_patches;
+ int patch_x = gl_InstanceID % textureSize(flow_tex, 0).x;
+ int patch_y = gl_InstanceID / textureSize(flow_tex, 0).x;
+
+ // Convert the patch index to being the full 0..1 range, to match where
+ // the motion search puts the patches. We don't bother with the locking
+ // to texel centers, though.
+ vec2 patch_center = ivec2(patch_x, patch_y) / (textureSize(flow_tex, 0) - 1.0);
// Increase the patch size a bit; since patch spacing is not necessarily
// an integer number of pixels, and we don't use conservative rasterization,
// all directions.
vec2 grown_pos = (position * 1.5) - 0.25;
- image_pos = patch_spacing * ivec2(patch_x, patch_y) + patch_size * grown_pos;
+ image_pos = patch_center + patch_size * (grown_pos - 0.5f);
// Find the flow value for this patch, and send it on to the fragment shader.
vec3 flow_du_and_mean_diff = texelFetch(flow_tex, ivec2(patch_x, patch_y), 0).xyz;