[Bf-blender-cvs] [d836adb2757] blender2.8: Draw Manager: Fix crash when trying to order an empty shading group.

[Clément Foucault]

Commit: d836adb2757d61a26687d1d89f83dcf9dea88e98
Author: Clément Foucault
Date:   Wed Nov 1 00:57:25 2017 +0100
Branches: blender2.8
https://developer.blender.org/rBd836adb2757d61a26687d1d89f83dcf9dea88e98

Draw Manager: Fix crash when trying to order an empty shading group.

This fix crash when using only the volume output with an alpha blend material

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

M	source/blender/draw/intern/draw_manager.c

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

diff --git a/source/blender/draw/intern/draw_manager.c b/source/blender/draw/intern/draw_manager.c
index 36008099b70..f23bbd3af45 100644
--- a/source/blender/draw/intern/draw_manager.c
+++ b/source/blender/draw/intern/draw_manager.c
@@ -1406,6 +1406,8 @@ static int pass_shgroup_dist_sort(void *thunk, const void *a, const void *b)
 	call_b = shgrp_b->calls.first;
 #endif
 
+	if (call_a == NULL) return -1;
+	if (call_b == NULL) return -1;
 
 	float tmp[3];
 	sub_v3_v3v3(tmp, zsortdata->origin, call_a->obmat[3]);