Merge pull request #7064 from JordanSucher/modify-3d-stroke-offset

modified stroke vertex shader

src/webgl/shaders/line.vert

@@ -88,19 +88,16 @@ void main() {
  0.25
  );
 
- // using a scale <1 moves the lines towards the camera
- // in order to prevent popping effects due to half of
- // the line disappearing behind the geometry faces.
- float scale = mix(1., 0.995, facingCamera);
-
  // Moving vertices slightly toward the camera
  // to avoid depth-fighting with the fill triangles.
- // Discussed here:
- // http://www.opengl.org/discussion_boards/ubbthreads.php?ubb=showflat&Number=252848 
- posp.xyz = posp.xyz * scale;
- posqIn.xyz = posqIn.xyz * scale;
- posqOut.xyz = posqOut.xyz * scale;
-
+ // This prevents popping effects due to half of
+ // the line disappearing behind the geometry faces.
+
+ float zOffset = mix(-0.00045, -1., facingCamera);
+ posp.z -= zOffset;
+ posqIn.z -= zOffset;
+ posqOut.z -= zOffset;
+
  vec4 p = uProjectionMatrix * posp;
  vec4 qIn = uProjectionMatrix * posqIn;
  vec4 qOut = uProjectionMatrix * posqOut;