1 files changed, 19 insertions, 0 deletions
diff --git a/source/blender/editors/render/render_preview.c b/source/blender/editors/render/render_preview.c
index 76b88b8df22..35130988aba 100644
--- a/source/blender/editors/render/render_preview.c
+++ b/source/blender/editors/render/render_preview.c
@@ -38,6 +38,8 @@
 #include "BLI_blenlib.h"
 #include "BLI_utildefines.h"
 
+#include "PIL_time.h"
+
 #include "BLO_readfile.h"
 
 #include "DNA_world_types.h"
@@ -1206,6 +1208,16 @@ static void icon_preview_startjob_all_sizes(void *customdata,
   IconPreview *ip = (IconPreview *)customdata;
   IconPreviewSize *cur_size;
 
+  /* Wait 2s to start rendering icon previews, to not bog down user interaction.
+   * Particularly important for heavy scenes and Eevee using OpenGL that blocks
+   * the user interface drawing. */
+  for (int i = 0; i < 20; i++) {
+    PIL_sleep_ms(100);
+    if (*stop) {
+      return;
+    }
+  }
+
   for (cur_size = ip->sizes.first; cur_size; cur_size = cur_size->next) {
     PreviewImage *prv = ip->owner;
 
@@ -1253,6 +1265,10 @@ static void icon_preview_startjob_all_sizes(void *customdata,
 
     common_preview_startjob(sp, stop, do_update, progress);
     shader_preview_free(sp);
+
+    if (*stop) {
+      break;
+    }
   }
 }
 
@@ -1470,6 +1486,9 @@ void ED_preview_shader_job(const bContext *C,
 void ED_preview_kill_jobs(wmWindowManager *wm, Main *UNUSED(bmain))
 {
   if (wm) {
+    /* This is called to stop all preview jobs before scene data changes, to
+     * avoid invalid memory access. */
     WM_jobs_kill(wm, NULL, common_preview_startjob);
+    WM_jobs_kill(wm, NULL, icon_preview_startjob_all_sizes);
   }
 }