Fix #28427: smooth faces flash momentarily when extruded using "extrude and move on normals" tool (E key)

Update normals just after extrude -- topology is changing when extruding
and normals for non-extruded faces should be recalculated after this.

1 files changed, 9 insertions, 0 deletions

diff --git a/source/blender/editors/mesh/editmesh_lib.c b/source/blender/editors/mesh/editmesh_lib.c
index b7ed6ec14ca..0afa2d01702 100644
--- a/source/blender/editors/mesh/editmesh_lib.c
+++ b/source/blender/editors/mesh/editmesh_lib.c
@@ -1141,6 +1141,9 @@ short extrudeflag_face_indiv(EditMesh *em, short UNUSED(flag), float *UNUSED(nor
 	
 	EM_select_flush(em);
 	
+	/* step 5; update normals after extrude */
+	recalc_editnormals(em);
+
 	return 'n';
 }
 
@@ -1206,6 +1209,9 @@ short extrudeflag_edges_indiv(EditMesh *em, short flag, float *nor)
 		if(eed->v1->f & eed->v2->f & flag) eed->f |= flag;
 	}
 	
+	/* update normals after extrude */
+	recalc_editnormals(em);
+
 	if(is_zero_v3(nor)) return 'g'; // g is grab
 	return 'n';  // n is for normal constraint
 }
@@ -1485,6 +1491,9 @@ static short extrudeflag_edge(Object *obedit, EditMesh *em, short UNUSED(flag),
 
 	EM_select_flush(em);
 
+	/* step 8; update normals after extrude */
+	recalc_editnormals(em);
+
 	if(is_zero_v3(nor)) return 'g'; // grab
 	return 'n'; // normal constraint 
 }