Option to lock the interface while rendering

Added function called WM_set_locked_interface which does
two things:

- Prevents event queue from being handled, so no operators
  (see below) or values are even possible to run or change.
  This prevents any kind of "destructive" action performed
  from user while rendering.

- Locks interface refresh for regions which does have lock
  set to truth in their template. Currently it's just a 3D
  viewport, but in the future more regions could be considered
  unsafe, or we could want to lock different parts of
  interface when doing different jobs.

  This is needed because 3D viewport could be using or changing
  the same data as renderer currently uses, leading to threading
  conflict.

  Notifiers are still allowed to handle, so render progress is
  seen on the screen, but would need to doublecheck on this, in
  terms some notifiers could be changing the data.

  For now interface locking happens for render job only in case
  "Lock Interface" checkbox is enabled.

  Other tools like backing would also benefit of this option.

  It is possible to mark operator as safe to be used in locked
  interface mode by adding OPTYPE_ALLOW_LOCKED bit to operator
  template flags.

  This bit is completely handled by wm_evem_system, not
  with operator run routines, so it's still possible to
  run operators from drivers and handlers.

  Currently allowed image editor navigation and zooming.

Reviewers: brecht, campbellbarton

Reviewed By: campbellbarton

Differential Revision: https://developer.blender.org/D142

2 files changed, 15 insertions, 13 deletions

diff --git a/source/blender/render/extern/include/RE_pipeline.h b/source/blender/render/extern/include/RE_pipeline.h
index 32c0a1d8535..bc07f0ce6c0 100644
--- a/source/blender/render/extern/include/RE_pipeline.h
+++ b/source/blender/render/extern/include/RE_pipeline.h
@@ -290,5 +290,7 @@ struct Scene *RE_GetScene(struct Render *re);
 
 int RE_is_rendering_allowed(struct Scene *scene, struct Object *camera_override, struct ReportList *reports);
 
+bool RE_allow_render_generic_object(struct Object *ob);
+
 #endif /* __RE_PIPELINE_H__ */
 
diff --git a/source/blender/render/intern/source/pipeline.c b/source/blender/render/intern/source/pipeline.c
index ec2644e4d9b..39bc571853a 100644
--- a/source/blender/render/intern/source/pipeline.c
+++ b/source/blender/render/intern/source/pipeline.c
@@ -1602,6 +1602,18 @@ static bool rlayer_node_uses_alpha(bNodeTree *ntree, bNode *node)
 	return false;
 }
 
+bool RE_allow_render_generic_object(Object *ob)
+{
+	/* override not showing object when duplis are used with particles */
+	if (ob->transflag & OB_DUPLIPARTS) {
+		/* pass */  /* let particle system(s) handle showing vs. not showing */
+	}
+	else if ((ob->transflag & OB_DUPLI) && !(ob->transflag & OB_DUPLIFRAMES)) {
+		return false;
+	}
+	return true;
+}
+
 /* Issue here is that it's possible that object which is used by boolean,
  * array or shrinkwrap modifiers weren't displayed in the viewport before
  * rendering. This leads to situations when apply() of this modifiers
@@ -1619,18 +1631,6 @@ static bool rlayer_node_uses_alpha(bNodeTree *ntree, bNode *node)
 #define DEPSGRAPH_WORKAROUND_HACK
 
 #ifdef DEPSGRAPH_WORKAROUND_HACK
-static bool allow_render_mesh_object(Object *ob)
-{
-	/* override not showing object when duplis are used with particles */
-	if (ob->transflag & OB_DUPLIPARTS) {
-		/* pass */  /* let particle system(s) handle showing vs. not showing */
-	}
-	else if ((ob->transflag & OB_DUPLI) && !(ob->transflag & OB_DUPLIFRAMES)) {
-		return false;
-	}
-	return true;
-}
-
 static void tag_dependend_objects_for_render(Scene *scene, int renderlay)
 {
 	Scene *sce_iter;
@@ -1643,7 +1643,7 @@ static void tag_dependend_objects_for_render(Scene *scene, int renderlay)
 		}
 
 		if (object->type == OB_MESH) {
-			if (allow_render_mesh_object(object)) {
+			if (RE_allow_render_generic_object(object)) {
 				ModifierData *md;
 				VirtualModifierData virtualModifierData;