X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=densify.vert;h=181c7f32b72203ed16244253097e0223fe4493c2;hb=3795723be95f2fe82f3c8b8b45b1a905b2c811fd;hp=e4db8fba94789e57145d7da20f1ccae455342290;hpb=957d873c387993c711249657f3080c5d686d7ea1;p=nageru

diff --git a/densify.vert b/densify.vert
index e4db8fb..181c7f3 100644
--- a/densify.vert
+++ b/densify.vert
@@ -1,25 +1,44 @@
 #version 450 core
+#extension GL_ARB_shader_viewport_layer_array : require
 
-in vec2 position;
+layout(location=0) in vec2 position;
 out vec2 image_pos;
 flat out vec2 flow_du;
+flat out float mean_diff;
+flat out int image0_layer, image1_layer;
 
-uniform int width_patches;
 uniform vec2 patch_size;  // In 0..1 coordinates.
-uniform vec2 patch_spacing;  // In 0..1 coordinates.
-uniform sampler2D flow_tex;
+uniform sampler2DArray flow_tex;
 
 void main()
 {
-	int patch_x = gl_InstanceID % width_patches;
-	int patch_y = gl_InstanceID / width_patches;
+	int num_patches = textureSize(flow_tex, 0).x * textureSize(flow_tex, 0).y;
+	int patch_layer = gl_InstanceID / num_patches;
+	int patch_x = gl_InstanceID % textureSize(flow_tex, 0).x;
+	int patch_y = (gl_InstanceID % num_patches) / textureSize(flow_tex, 0).x;
 
-	// TODO: Lock the bottom left of the patch to an integer number of pixels?
+	// 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).xy - 1.0);
 
-	image_pos = patch_spacing * ivec2(patch_x, patch_y) + patch_size * position;
+	// Increase the patch size a bit; since patch spacing is not necessarily
+	// an integer number of pixels, and we don't use conservative rasterization,
+	// we could be missing the outer edges of the patch. And it seemingly helps
+	// a little bit in general to have some more candidates as well -- although
+	// this is measured without variational refinement, so it might be moot
+	// with it.
+	//
+	// This maps [0.0,1.0] to [-0.25,1.25], ie. extends the patch by 25% in
+	// all directions.
+	vec2 grown_pos = (position * 1.5) - 0.25;
+
+	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.
-	flow_du = texelFetch(flow_tex, ivec2(patch_x, patch_y), 0).xy;
+	vec3 flow_du_and_mean_diff = texelFetch(flow_tex, ivec3(patch_x, patch_y, patch_layer), 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:
 	//
@@ -28,4 +47,9 @@ void main()
 	//   0.000  0.000 -2.000 -1.000
 	//   0.000  0.000  0.000  1.000
 	gl_Position = vec4(2.0 * image_pos.x - 1.0, 2.0 * image_pos.y - 1.0, -1.0, 1.0);
+	gl_Layer = patch_layer;
+
+	// Forward flow (0) goes from 0 to 1. Backward flow (1) goes from 1 to 0.
+	image0_layer = patch_layer;
+	image1_layer = 1 - patch_layer;
 }