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.

7 files changed, 14 insertions, 13 deletions

diff --git a/source/blender/bmesh/operators/bmo_bisect_plane.c b/source/blender/bmesh/operators/bmo_bisect_plane.c
index 2663f271b6e..55b6337bea4 100644
--- a/source/blender/bmesh/operators/bmo_bisect_plane.c
+++ b/source/blender/bmesh/operators/bmo_bisect_plane.c
@@ -50,7 +50,7 @@ void bmo_bisect_plane_exec(BMesh *bm, BMOperator *op)
   BMO_slot_vec_get(op->slots_in, "plane_no", plane_no);
 
   if (is_zero_v3(plane_no)) {
-    BMO_error_raise(bm, op, "Zero normal given");
+    BMO_error_raise(bm, op, BMO_ERROR_CANCEL, "Zero normal given");
     return;
   }
 
diff --git a/source/blender/bmesh/operators/bmo_bridge.c b/source/blender/bmesh/operators/bmo_bridge.c
index 005b8a2f5e8..fb913d4f19f 100644
--- a/source/blender/bmesh/operators/bmo_bridge.c
+++ b/source/blender/bmesh/operators/bmo_bridge.c
@@ -576,12 +576,12 @@ void bmo_bridge_loops_exec(BMesh *bm, BMOperator *op)
   BM_mesh_edgeloops_calc_center(bm, &eloops);
 
   if (count < 2) {
-    BMO_error_raise(bm, op, "Select at least two edge loops");
+    BMO_error_raise(bm, op, BMO_ERROR_CANCEL, "Select at least two edge loops");
     goto cleanup;
   }
 
   if (use_pairs && (count % 2)) {
-    BMO_error_raise(bm, op, "Select an even number of loops to bridge pairs");
+    BMO_error_raise(bm, op, BMO_ERROR_CANCEL, "Select an even number of loops to bridge pairs");
     goto cleanup;
   }
 
@@ -595,7 +595,7 @@ void bmo_bridge_loops_exec(BMesh *bm, BMOperator *op)
       }
     }
     if (!match) {
-      BMO_error_raise(bm, op, "Selected loops must have equal edge counts");
+      BMO_error_raise(bm, op, BMO_ERROR_CANCEL, "Selected loops must have equal edge counts");
       goto cleanup;
     }
   }
diff --git a/source/blender/bmesh/operators/bmo_connect.c b/source/blender/bmesh/operators/bmo_connect.c
index b701c1291a6..abc040f7564 100644
--- a/source/blender/bmesh/operators/bmo_connect.c
+++ b/source/blender/bmesh/operators/bmo_connect.c
@@ -211,7 +211,7 @@ void bmo_connect_verts_exec(BMesh *bm, BMOperator *op)
   /* connect faces */
   while ((f = BLI_LINKSTACK_POP(faces))) {
     if (bm_face_connect_verts(bm, f, check_degenerate) == -1) {
-      BMO_error_raise(bm, op, "Could not connect vertices");
+      BMO_error_raise(bm, op, BMO_ERROR_FATAL, "Could not connect vertices");
     }
   }
 
diff --git a/source/blender/bmesh/operators/bmo_dissolve.c b/source/blender/bmesh/operators/bmo_dissolve.c
index c0ce63fb0eb..efba0ec99ec 100644
--- a/source/blender/bmesh/operators/bmo_dissolve.c
+++ b/source/blender/bmesh/operators/bmo_dissolve.c
@@ -257,7 +257,7 @@ void bmo_dissolve_faces_exec(BMesh *bm, BMOperator *op)
     }
   }
 
-  BLI_assert(!BMO_error_occurred(bm));
+  BLI_assert(!BMO_error_occurred_at_level(bm, BMO_ERROR_FATAL));
 
   BMO_slot_buffer_from_enabled_flag(bm, op, op->slots_out, "region.out", BM_FACE, FACE_NEW);
 
diff --git a/source/blender/bmesh/operators/bmo_fill_grid.c b/source/blender/bmesh/operators/bmo_fill_grid.c
index 4ba7dbad736..2e09b21c9cc 100644
--- a/source/blender/bmesh/operators/bmo_fill_grid.c
+++ b/source/blender/bmesh/operators/bmo_fill_grid.c
@@ -619,6 +619,7 @@ void bmo_grid_fill_exec(BMesh *bm, BMOperator *op)
      * extract two 'rail' loops from a single edge loop, see T72075. */
     BMO_error_raise(bm,
                     op,
+                    BMO_ERROR_CANCEL,
                     "Select two edge loops "
                     "or a single closed edge loop from which two edge loops can be calculated");
     goto cleanup;
@@ -633,7 +634,7 @@ void bmo_grid_fill_exec(BMesh *bm, BMOperator *op)
   v_b_last = ((LinkData *)BM_edgeloop_verts_get(estore_b)->last)->data;
 
   if (BM_edgeloop_is_closed(estore_a) || BM_edgeloop_is_closed(estore_b)) {
-    BMO_error_raise(bm, op, "Closed loops unsupported");
+    BMO_error_raise(bm, op, BMO_ERROR_CANCEL, "Closed loops unsupported");
     goto cleanup;
   }
 
@@ -671,7 +672,7 @@ void bmo_grid_fill_exec(BMesh *bm, BMOperator *op)
   bm_edgeloop_flag_set(estore_b, BM_ELEM_HIDDEN, false);
 
   if (BLI_listbase_is_empty(&eloops_rail)) {
-    BMO_error_raise(bm, op, "Loops are not connected by wire/boundary edges");
+    BMO_error_raise(bm, op, BMO_ERROR_CANCEL, "Loops are not connected by wire/boundary edges");
     goto cleanup;
   }
 
@@ -679,7 +680,7 @@ void bmo_grid_fill_exec(BMesh *bm, BMOperator *op)
   BLI_assert(v_a_last != v_b_last);
 
   if (BM_edgeloop_overlap_check(estore_rail_a, estore_rail_b)) {
-    BMO_error_raise(bm, op, "Connecting edge loops overlap");
+    BMO_error_raise(bm, op, BMO_ERROR_CANCEL, "Connecting edge loops overlap");
     goto cleanup;
   }
 
diff --git a/source/blender/bmesh/operators/bmo_hull.c b/source/blender/bmesh/operators/bmo_hull.c
index dd2fe52293f..0801300b6c2 100644
--- a/source/blender/bmesh/operators/bmo_hull.c
+++ b/source/blender/bmesh/operators/bmo_hull.c
@@ -554,7 +554,7 @@ void bmo_convex_hull_exec(BMesh *bm, BMOperator *op)
 
   /* Verify that at least three verts in the input */
   if (!hull_num_input_verts_is_ok(op)) {
-    BMO_error_raise(bm, op, "Requires at least three vertices");
+    BMO_error_raise(bm, op, BMO_ERROR_CANCEL, "Requires at least three vertices");
     return;
   }
 
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;
     }