Fix T78308: Weight Transfer Operator "Deform Pose Bones" destination setting doesn't work.

Some modes were working by mere chance in that ugly 'reversed' case, but
the to/from selection modes were not properly swapped...

Should also be safe for 2.83.

1 files changed, 6 insertions, 2 deletions

diff --git a/source/blender/editors/object/object_data_transfer.c b/source/blender/editors/object/object_data_transfer.c
index 1e2b7702dc5..a44c911a5f1 100644
--- a/source/blender/editors/object/object_data_transfer.c
+++ b/source/blender/editors/object/object_data_transfer.c
@@ -424,8 +424,8 @@ static int data_transfer_exec(bContext *C, wmOperator *op)
   const float ray_radius = RNA_float_get(op->ptr, "ray_radius");
   const float islands_precision = RNA_float_get(op->ptr, "islands_precision");
 
-  const int layers_src = RNA_enum_get(op->ptr, "layers_select_src");
-  const int layers_dst = RNA_enum_get(op->ptr, "layers_select_dst");
+  int layers_src = RNA_enum_get(op->ptr, "layers_select_src");
+  int layers_dst = RNA_enum_get(op->ptr, "layers_select_dst");
   int layers_select_src[DT_MULTILAYER_INDEX_MAX] = {0};
   int layers_select_dst[DT_MULTILAYER_INDEX_MAX] = {0};
   const int fromto_idx = BKE_object_data_transfer_dttype_to_srcdst_index(data_type);
@@ -451,6 +451,10 @@ static int data_transfer_exec(bContext *C, wmOperator *op)
     return OPERATOR_CANCELLED;
   }
 
+  if (reverse_transfer) {
+    SWAP(int, layers_src, layers_dst);
+  }
+
   if (fromto_idx != DT_MULTILAYER_INDEX_INVALID) {
     layers_select_src[fromto_idx] = layers_src;
     layers_select_dst[fromto_idx] = layers_dst;