BMesh: remove redundant mesh-backups from EDBM_op_* API

Using BMesh operators through the edit-mesh API created a full copy
of the mesh so it was possible to restore the mesh in case
one of the operators raised an error.

Remove support for automatic backup/restore from the EDBM_op_* API's
as it adds significant overhead and was rarely used.

Operators that need this can use the BMBackup API to backup & restore
the mesh in case of failure.

Add warning levels to BMO_error_raise so operators can report problems
without it being interpreted as a request to cancel the operation.

For high-poly meshes creating and freeing a full copy is an expensive
operation, removing this gives a speedup of ~1.77x for most operators
except for "connect_verts" / "connect_vert_pair"
which still uses this functionality.

1 files changed, 3 insertions, 3 deletions

diff --git a/source/blender/bmesh/operators/bmo_subdivide_edgering.c b/source/blender/bmesh/operators/bmo_subdivide_edgering.c
index caca24f4409..d015b715a69 100644
--- a/source/blender/bmesh/operators/bmo_subdivide_edgering.c
+++ b/source/blender/bmesh/operators/bmo_subdivide_edgering.c
@@ -1143,7 +1143,7 @@ void bmo_subdivide_edgering_exec(BMesh *bm, BMOperator *op)
   count = BM_mesh_edgeloops_find(bm, &eloops_rim, bm_edge_rim_test_cb, (void *)bm);
 
   if (count < 2) {
-    BMO_error_raise(bm, op, "No edge rings found");
+    BMO_error_raise(bm, op, BMO_ERROR_CANCEL, "No edge rings found");
     goto cleanup;
   }
   else if (count == 2) {
@@ -1167,7 +1167,7 @@ void bmo_subdivide_edgering_exec(BMesh *bm, BMOperator *op)
       changed = true;
     }
     else {
-      BMO_error_raise(bm, op, "Edge-ring pair isn't connected");
+      BMO_error_raise(bm, op, BMO_ERROR_CANCEL, "Edge-ring pair isn't connected");
       goto cleanup;
     }
   }
@@ -1179,7 +1179,7 @@ void bmo_subdivide_edgering_exec(BMesh *bm, BMOperator *op)
     LoopPairStore **lpair_arr;
 
     if (eloop_pairs_gs == NULL) {
-      BMO_error_raise(bm, op, "Edge-rings are not connected");
+      BMO_error_raise(bm, op, BMO_ERROR_CANCEL, "Edge-rings are not connected");
       goto cleanup;
     }