Fix a GLSL syntax error that tripped up NVIDIA.

[nageru] / motion_search.frag

diff --git a/motion_search.frag b/motion_search.frag
index a32868b21669ba4b761dbb93852d517975c86511..136d316ef4cfe43ac4e4604e12379cec81be9385 100644 (file)
--- a/motion_search.frag
+++ b/motion_search.frag
@@ -36,20 +36,23 @@
  */
 
 const uint patch_size = 12;
-const uint num_iterations = 16;
+const uint num_iterations = 8;
 
 in vec2 flow_tc;
-in vec2 patch_bottom_left_texel;  // Center of bottom-left texel of patch.
+in vec2 patch_center;
 out vec3 out_flow;
 
 uniform sampler2D flow_tex, grad0_tex, image0_tex, image1_tex;
-uniform vec2 image_size, inv_image_size, inv_prev_level_size;
+uniform vec2 inv_image_size, inv_prev_level_size;
 
 void main()
 {
-       // Lock patch_bottom_left_texel to an integer, so that we never get
-       // any bilinear artifacts for the gradient.
-       vec2 base = (round(patch_bottom_left_texel * image_size - vec2(0.5, 0.5)) + vec2(0.5, 0.5))
+       vec2 image_size = textureSize(image0_tex, 0);
+
+       // Lock the patch center to an integer, so that we never get
+       // any bilinear artifacts for the gradient. (NOTE: This assumes an
+       // even patch size.) Then calculate the bottom-left texel of the patch.
+       vec2 base = (round(patch_center * image_size) - (0.5f * patch_size - 0.5f))
                * inv_image_size;
 
        // First, precompute the pseudo-Hessian for the template patch.
@@ -121,7 +124,7 @@ void main()
                //   sum(S^T * (x - y)) = [what we calculated] - (µ1 - µ2) sum(S^T)
                //
                // so we can just subtract away the mean difference here.
-               mean_diff = (warped_sum - template_sum) * (1.0 / (patch_size * patch_size));
+               mean_diff = (warped_sum - template_sum) * (1.0 / float(patch_size * patch_size));
                du -= grad_sum * mean_diff;
 
                if (i == 0) {