[Bf-blender-cvs] [78cf61cc629] master: Fix T72690: Do not draw points behind the viewport camera in the paint cursor

[Pablo Dobarro]

Commit: 78cf61cc6292eb66c5835cf337ad8fb3e1c259b2
Author: Pablo Dobarro
Date:   Thu Jan 23 21:41:30 2020 +0100
Branches: master
https://developer.blender.org/rB78cf61cc6292eb66c5835cf337ad8fb3e1c259b2

Fix T72690: Do not draw points behind the viewport camera in the paint cursor

In some situations the symmetry point may be behind the camera, so the
projection is inverted and it looks wrong. This avoids drawing points in
screen space when they are behind the camera.

Reviewed By: jbakker

Maniphest Tasks: T72690

Differential Revision: https://developer.blender.org/D6487

===================================================================

M	source/blender/editors/sculpt_paint/paint_cursor.c

===================================================================

diff --git a/source/blender/editors/sculpt_paint/paint_cursor.c b/source/blender/editors/sculpt_paint/paint_cursor.c
index 19b4b9f569c..cf796c7dd3c 100644
--- a/source/blender/editors/sculpt_paint/paint_cursor.c
+++ b/source/blender/editors/sculpt_paint/paint_cursor.c
@@ -1103,8 +1103,11 @@ static void cursor_draw_point_screen_space(
   copy_v3_v3(location, true_location);
   mul_m4_v3(obmat, location);
   ED_view3d_project(ar, location, translation_vertex_cursor);
-  imm_draw_circle_fill_3d(
-      gpuattr, translation_vertex_cursor[0], translation_vertex_cursor[1], size, 10);
+  /* Do not draw points behind the view. Z [near, far] is mapped to [-1, 1]. */
+  if (translation_vertex_cursor[2] <= 1.0f) {
+    imm_draw_circle_fill_3d(
+        gpuattr, translation_vertex_cursor[0], translation_vertex_cursor[1], size, 10);
+  }
 }
 
 static void cursor_draw_tiling_preview(const uint gpuattr,