[Bf-blender-cvs] [3934c43ef7f] uvimage-editor-drawing: Snap vertices to pixel grid

[Jeroen Bakker]

Commit: 3934c43ef7f2d2c9a884d88cd27272404c8a379c
Author: Jeroen Bakker
Date:   Thu Sep 10 08:11:33 2020 +0200
Branches: uvimage-editor-drawing
https://developer.blender.org/rB3934c43ef7f2d2c9a884d88cd27272404c8a379c

Snap vertices to pixel grid

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M	source/blender/draw/engines/overlay/shaders/edit_uv_edges_vert.glsl

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diff --git a/source/blender/draw/engines/overlay/shaders/edit_uv_edges_vert.glsl b/source/blender/draw/engines/overlay/shaders/edit_uv_edges_vert.glsl
index 41316496e5a..e5ec8ef395e 100644
--- a/source/blender/draw/engines/overlay/shaders/edit_uv_edges_vert.glsl
+++ b/source/blender/draw/engines/overlay/shaders/edit_uv_edges_vert.glsl
@@ -13,6 +13,11 @@ void main()
 {
   vec3 world_pos = point_object_to_world(vec3(u, 0.0));
   gl_Position = point_world_to_ndc(world_pos);
+  /* Snap vertices to the pixel grid to reduce artifacts. */
+  vec2 half_viewport_res = sizeViewport.xy * 0.5;
+  vec2 half_pixel_offset = sizeViewportInv * 0.5;
+  gl_Position.xy = round(gl_Position.xy * half_viewport_res) / half_viewport_res +
+                   half_pixel_offset;
 
   bool is_select = (flag & VERT_UV_SELECT) != 0;
   if (is_select) {