1 files changed, 7 insertions, 1 deletions
diff --git a/source/blender/gpu/shaders/gpu_shader_3D_line_dashed_uniform_color_vert.glsl b/source/blender/gpu/shaders/gpu_shader_3D_line_dashed_uniform_color_vert.glsl
index 7c317ecfb8c..aefa47275f5 100644
--- a/source/blender/gpu/shaders/gpu_shader_3D_line_dashed_uniform_color_vert.glsl
+++ b/source/blender/gpu/shaders/gpu_shader_3D_line_dashed_uniform_color_vert.glsl
@@ -13,15 +13,21 @@ uniform mat4 ModelMatrix;
 #endif
 
 uniform vec4 color;
+uniform vec2 viewport_size;
 
 in vec3 pos;
 
-out vec4 color_vert;
+flat out vec4 color_vert;
+
+/* We leverage hardware interpolation to compute distance along the line. */
+noperspective out vec2 stipple_pos; /* In screen space */
+flat out vec2 stipple_start;        /* In screen space */
 
 void main()
 {
   vec4 pos_4d = vec4(pos, 1.0);
   gl_Position = ModelViewProjectionMatrix * pos_4d;
+  stipple_start = stipple_pos = viewport_size * 0.5 * (gl_Position.xy / gl_Position.w);
   color_vert = color;
 #ifdef USE_WORLD_CLIP_PLANES
   world_clip_planes_calc_clip_distance((ModelMatrix * pos_4d).xyz);