BMesh: rip-tool can now split off isolated fans

Useful since there wasn't a good way to do this previously.

1 files changed, 29 insertions, 2 deletions

diff --git a/source/blender/editors/mesh/editmesh_rip.c b/source/blender/editors/mesh/editmesh_rip.c
index e9fc12f3252..abd88ae65aa 100644
--- a/source/blender/editors/mesh/editmesh_rip.c
+++ b/source/blender/editors/mesh/editmesh_rip.c
@@ -559,9 +559,10 @@ static int edbm_rip_invoke__vert(bContext *C, wmOperator *op, const wmEvent *eve
 		}
 	}
 
-	/* this should be impossible, but sanity checks are a good thing */
-	if (!v)
+	/* (v == NULL) should be impossible */
+	if ((v == NULL) || (v->e == NULL)) {
 		return OPERATOR_CANCELLED;
+	}
 
 	is_wire = BM_vert_is_wire(v);
 
@@ -621,6 +622,32 @@ static int edbm_rip_invoke__vert(bContext *C, wmOperator *op, const wmEvent *eve
 		}
 	}
 
+	if (e2) {
+		/* Try to split off a non-manifold fan (when we have multiple disconnected fans) */
+
+		/* note: we're lazy here and first split then check there are any faces remaining,
+		 * this isn't good practice, however its less hassle then checking for multiple-disconnected regions */
+		BMLoop *l_sep = e2->l->v == v ? e2->l : e2->l->next;
+		BMVert *v_new;
+		BLI_assert(l_sep->v == v);
+		v_new = bmesh_urmv_loop_region(bm, l_sep);
+		if (BM_vert_find_first_loop(v)) {
+			BM_vert_select_set(bm, v, false);
+			BM_select_history_remove(bm, v);
+
+			BM_vert_select_set(bm, v_new, true);
+			if (ese.ele) {
+				BM_select_history_store(bm, v_new);
+			}
+
+			return OPERATOR_FINISHED;
+		}
+		else {
+			/* rewind */
+			BM_vert_splice(bm, v, v_new);
+		}
+	}
+
 	/* should we go ahead with edge rip or do we need to do special case, split off vertex?:
 	 * split off vertex if...
 	 * - we cant find an edge - this means we are ripping a faces vert that is connected to other