Fix #35404: crash in file save with python code that accesses mesh from panel.

On file save the mesh gets loads from the editmesh but the derived mesh caches
wer not cleared. This usually happens through the depsgraph but it needs to be
done manually here. Most changes are some refactoring to deduplicate derived
mesh freeing code.

1 files changed, 41 insertions, 25 deletions

diff --git a/source/blender/blenkernel/intern/object.c b/source/blender/blenkernel/intern/object.c
index 741c4f5429e..3779aa8cd88 100644
--- a/source/blender/blenkernel/intern/object.c
+++ b/source/blender/blenkernel/intern/object.c
@@ -241,20 +241,34 @@ void BKE_object_link_modifiers(struct Object *ob_dst, struct Object *ob_src)
 	/* TODO: smoke?, cloth? */
 }
 
-/* here we will collect all local displist stuff */
-/* also (ab)used in depsgraph */
-void BKE_object_free_display(Object *ob)
+/* free data derived from mesh, called when mesh changes or is freed */
+void BKE_object_free_derived_caches(Object *ob)
 {
-	if (ob->derivedDeform) {
-		ob->derivedDeform->needsFree = 1;
-		ob->derivedDeform->release(ob->derivedDeform);
-		ob->derivedDeform = NULL;
+	/* also serves as signal to remake texspace */
+	if (ob->type == OB_MESH) {
+		Mesh *me = ob->data;
+
+		if (me->bb) {
+			MEM_freeN(me->bb);
+			me->bb = NULL;
+		}
+	}
+
+	if (ob->bb) {
+		MEM_freeN(ob->bb);
+		ob->bb = NULL;
 	}
+
 	if (ob->derivedFinal) {
 		ob->derivedFinal->needsFree = 1;
 		ob->derivedFinal->release(ob->derivedFinal);
 		ob->derivedFinal = NULL;
 	}
+	if (ob->derivedDeform) {
+		ob->derivedDeform->needsFree = 1;
+		ob->derivedDeform->release(ob->derivedDeform);
+		ob->derivedDeform = NULL;
+	}
 	
 	BKE_displist_free(&ob->disp);
 }
@@ -264,7 +278,7 @@ void BKE_object_free(Object *ob)
 {
 	int a;
 	
-	BKE_object_free_display(ob);
+	BKE_object_free_derived_caches(ob);
 	
 	/* disconnect specific data, but not for lib data (might be indirect data, can get relinked) */
 	if (ob->data) {
@@ -2790,27 +2804,29 @@ void BKE_object_sculpt_modifiers_changed(Object *ob)
 {
 	SculptSession *ss = ob->sculpt;
 
-	if (!ss->cache) {
-		/* we free pbvh on changes, except during sculpt since it can't deal with
-		 * changing PVBH node organization, we hope topology does not change in
-		 * the meantime .. weak */
-		if (ss->pbvh) {
-			BKE_pbvh_free(ss->pbvh);
-			ss->pbvh = NULL;
-		}
+	if (ss) {
+		if (!ss->cache) {
+			/* we free pbvh on changes, except during sculpt since it can't deal with
+			 * changing PVBH node organization, we hope topology does not change in
+			 * the meantime .. weak */
+			if (ss->pbvh) {
+				BKE_pbvh_free(ss->pbvh);
+				ss->pbvh = NULL;
+			}
 
-		free_sculptsession_deformMats(ob->sculpt);
-	}
-	else {
-		PBVHNode **nodes;
-		int n, totnode;
+			free_sculptsession_deformMats(ob->sculpt);
+		}
+		else {
+			PBVHNode **nodes;
+			int n, totnode;
 
-		BKE_pbvh_search_gather(ss->pbvh, NULL, NULL, &nodes, &totnode);
+			BKE_pbvh_search_gather(ss->pbvh, NULL, NULL, &nodes, &totnode);
 
-		for (n = 0; n < totnode; n++)
-			BKE_pbvh_node_mark_update(nodes[n]);
+			for (n = 0; n < totnode; n++)
+				BKE_pbvh_node_mark_update(nodes[n]);
 
-		MEM_freeN(nodes);
+			MEM_freeN(nodes);
+		}
 	}
 }