From 4ae00358e8c5ba0b3603a821aa2e3e5d98d1d2d2 Mon Sep 17 00:00:00 2001
From: Ryan Schmidt <rms@rms80.com>
Date: Tue, 29 May 2018 23:05:03 -0400
Subject: [PATCH] Mesh.AppendTriangle can return multiple failure codes,
 InvalidID check is not sufficient.

---
 mesh/MeshEditor.cs           | 16 +++++++++-------
 mesh_ops/SimpleHoleFiller.cs |  8 ++++----
 2 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/mesh/MeshEditor.cs b/mesh/MeshEditor.cs
index 8f201332..c9fc872b 100644
--- a/mesh/MeshEditor.cs
+++ b/mesh/MeshEditor.cs
@@ -72,7 +72,7 @@ public virtual int[] AddTriangleFan_OrderedVertexLoop(int center, int[] vertex_l
 
                 Index3i newT = new Index3i(center, b, a);
                 int new_tid = Mesh.AppendTriangle(newT, group_id);
-                if (new_tid == DMesh3.InvalidID)
+                if (new_tid < 0)
                     goto operation_failed;
 
                 new_tris[i] = new_tid;
@@ -109,7 +109,7 @@ public virtual int[] AddTriangleFan_OrderedEdgeLoop(int center, int[] edge_loop,
 
                 Index3i newT = new Index3i(center, b, a);
                 int new_tid = Mesh.AppendTriangle(newT, group_id);
-                if (new_tid == DMesh3.InvalidID)
+                if (new_tid < 0)
                     goto operation_failed;
 
                 new_tris[i] = new_tid;
@@ -156,7 +156,7 @@ public virtual int[] StitchLoop(int[] vloop1, int[] vloop2, int group_id = -1)
                 int tid1 = Mesh.AppendTriangle(t1, group_id);
                 int tid2 = Mesh.AppendTriangle(t2, group_id);
 
-                if (tid1 == DMesh3.InvalidID || tid2 == DMesh3.InvalidID)
+                if (tid1 < 0 || tid2 < 0)
                     goto operation_failed;
 
                 new_tris[2 * i] = tid1;
@@ -218,7 +218,7 @@ public virtual int[] StitchUnorderedEdges(List<Index2i> EdgePairs, int group_id
                 int tid1 = Mesh.AppendTriangle(t1, group_id);
                 int tid2 = Mesh.AppendTriangle(t2, group_id);
 
-                if (tid1 == DMesh3.InvalidID || tid2 == DMesh3.InvalidID)
+                if (tid1 < 0 || tid2 < 0)
                     goto operation_failed;
 
                 new_tris[2 * i] = tid1;
@@ -268,7 +268,7 @@ public virtual int[] StitchSpan(IList<int> vspan1, IList<int> vspan2, int group_
                 int tid1 = Mesh.AppendTriangle(t1, group_id);
                 int tid2 = Mesh.AppendTriangle(t2, group_id);
 
-                if (tid1 == DMesh3.InvalidID || tid2 == DMesh3.InvalidID)
+                if (tid1 < 0 || tid2 < 0)
                     goto operation_failed;
 
                 new_tris[2 * i] = tid1;
@@ -539,9 +539,10 @@ static int bowtie_sorter(List<int> l1, List<int> l2) {
 
         /// <summary>
         /// Disconnect all bowtie vertices in mesh. Iterates because sometimes
-        /// disconnecting a bowtie creates new bowties (how??)
+		/// disconnecting a bowtie creates new bowties (how??).
+		/// Returns number of remaining bowties after iterations.
         /// </summary>
-        public void DisconnectAllBowties(int nMaxIters = 10)
+        public int DisconnectAllBowties(int nMaxIters = 10)
         {
             List<int> bowties = new List<int>(MeshIterators.BowtieVertices(Mesh));
             int iter = 0;
@@ -550,6 +551,7 @@ public void DisconnectAllBowties(int nMaxIters = 10)
                     DisconnectBowtie(vid);
                 bowties = new List<int>(MeshIterators.BowtieVertices(Mesh));
             }
+			return bowties.Count;
         }
 
 
diff --git a/mesh_ops/SimpleHoleFiller.cs b/mesh_ops/SimpleHoleFiller.cs
index 5ac92f55..1b0e072f 100644
--- a/mesh_ops/SimpleHoleFiller.cs
+++ b/mesh_ops/SimpleHoleFiller.cs
@@ -41,7 +41,7 @@ public virtual bool Fill(int group_id = -1)
             if ( Loop.Vertices.Length == 3 ) {
                 Index3i tri = new Index3i(Loop.Vertices[0], Loop.Vertices[2], Loop.Vertices[1]);
                 int new_tid = Mesh.AppendTriangle(tri, group_id);
-                if (new_tid == DMesh3.InvalidID)
+                if (new_tid < 0)
                     return false;
                 NewTriangles = new int[1] { new_tid };
                 NewVertex = DMesh3.InvalidID;
@@ -72,9 +72,9 @@ public virtual bool Fill(int group_id = -1)
             if ( NewTriangles == null ) {
                 Mesh.RemoveVertex(NewVertex, true, false);
                 NewVertex = DMesh3.InvalidID;
-            }
-
-            return true;
+				return false;
+            } else 
+            	return true;
 
         }