[Bf-blender-cvs] [28c20325798] master: Fix T80705: Single Image Texture Painting Crash

[Jeroen Bakker]

Commit: 28c203257984ecee1c2517a0985b6c073403743d
Author: Jeroen Bakker
Date:   Mon Sep 14 10:45:20 2020 +0200
Branches: master
https://developer.blender.org/rB28c203257984ecee1c2517a0985b6c073403743d

Fix T80705: Single Image Texture Painting Crash

Regression introduced by {D8234}; GPU textures can be requested without
an image user.

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

M	source/blender/blenkernel/intern/image_gpu.c

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

diff --git a/source/blender/blenkernel/intern/image_gpu.c b/source/blender/blenkernel/intern/image_gpu.c
index f37e038e69e..8e2e3fd621c 100644
--- a/source/blender/blenkernel/intern/image_gpu.c
+++ b/source/blender/blenkernel/intern/image_gpu.c
@@ -272,10 +272,14 @@ static GPUTexture *image_get_gpu_texture(Image *ima,
    * context and might as well ensure we have as much space free as possible. */
   gpu_free_unused_buffers();
 
-  /* Free GPU textures when requesting a different render pass/layer. */
-  if (ima->gpu_pass != iuser->pass || ima->gpu_layer != iuser->layer) {
-    ima->gpu_pass = iuser->pass;
-    ima->gpu_layer = iuser->layer;
+  /* Free GPU textures when requesting a different render pass/layer.
+   * When `iuser` isn't set (texture painting single image mode) we assume that
+   * the current `pass` and `layer` should be 0. */
+  short requested_pass = iuser ? iuser->pass : 0;
+  short requested_layer = iuser ? iuser->layer : 0;
+  if (ima->gpu_pass != requested_pass || ima->gpu_layer != requested_layer) {
+    ima->gpu_pass = requested_pass;
+    ima->gpu_layer = requested_layer;
     ima->gpuflag |= IMA_GPU_REFRESH;
   }