Hopefully fixed bug #5437, sculpt - seam selection flushing eats lots of ram on low multires level

This appears to have been caused by the excessive amount of memory that multires was eating up every time an edit operation pushed a new undo copy. Added a hack for multires that allows it to use the same multires data for multiple undo copies until the user actually changes levels (which is when multires data is actually updated.)

1 files changed, 32 insertions, 4 deletions

diff --git a/source/blender/src/editmesh.c b/source/blender/src/editmesh.c
index f5b0c432b3a..a71c70e0f91 100644
--- a/source/blender/src/editmesh.c
+++ b/source/blender/src/editmesh.c
@@ -1783,6 +1783,10 @@ typedef struct EditSelectionC{
 	int index;
 }EditSelectionC;
 
+typedef struct EM_MultiresUndo {
+	int users;
+	Multires *mr;
+} EM_MultiresUndo;
 
 typedef struct UndoMesh {
 	EditVertC *verts;
@@ -1794,7 +1798,7 @@ typedef struct UndoMesh {
 	RetopoPaintData *retopo_paint_data;
 	char retopo_mode;
 	CustomData vdata, fdata;
-	Multires *mr;
+	EM_MultiresUndo *mru;
 } UndoMesh;
 
 /* for callbacks */
@@ -1810,7 +1814,14 @@ static void free_undoMesh(void *umv)
 	if(um->retopo_paint_data) retopo_free_paint_data(um->retopo_paint_data);
 	CustomData_free(&um->vdata, um->totvert);
 	CustomData_free(&um->fdata, um->totface);
-	if(um->mr) multires_free(um->mr);
+	if(um->mru) {
+		--um->mru->users;
+		if(um->mru->users==0) {
+			multires_free(um->mru->mr);
+			um->mru->mr= NULL;
+			MEM_freeN(um->mru);
+		}
+	}
 	MEM_freeN(um);
 }
 
@@ -1905,7 +1916,24 @@ static void *editMesh_to_undoMesh(void)
 	um->retopo_paint_data= retopo_paint_data_copy(em->retopo_paint_data);
 	um->retopo_mode= em->retopo_mode;
 	
-	um->mr = get_mesh(G.obedit)->mr ? multires_copy(get_mesh(G.obedit)->mr) : NULL;
+	{
+		Multires *mr= get_mesh(G.obedit)->mr;
+		UndoMesh *prev= undo_editmode_get_prev();
+		
+		um->mru= NULL;
+		
+		if(mr) {
+			if(prev && prev->mru && prev->mru->mr && prev->mru->mr->current == mr->current) {
+				um->mru= prev->mru;
+				++um->mru->users;
+			}
+			else {
+				um->mru= MEM_callocN(sizeof(EM_MultiresUndo), "EM_MultiresUndo");
+				um->mru->users= 1;
+				um->mru->mr= multires_copy(mr);
+			}
+		}
+	}
 	
 	return um;
 }
@@ -2022,7 +2050,7 @@ static void undoMesh_to_editMesh(void *umv)
 		Mesh *me= get_mesh(G.obedit);
 		multires_free(me->mr);
 		me->mr= NULL;
-		if(um->mr) me->mr= multires_copy(um->mr);
+		if(um->mru && um->mru->mr) me->mr= multires_copy(um->mru->mr);
 	}
 }