Fixed bug where pixel was written twice, because geometry from vtile...

Fixed bug where pixel was written twice, because geometry from vtile overlapped twice same pixel, resulting in incorrect mapping.

Runtime/VectorTile.cs

@@ -408,6 +408,8 @@ namespace Wander
             UnityEngine.Debug.Assert( resolution > 1, "Must be at least 2." );
 
             byte [] texture = new byte[resolution*resolution/2];
+            bool [] written = new bool[resolution*resolution];
+
             int d = 4096 / resolution;
             int shift = -1;
             while (d!=0)
@@ -430,6 +432,7 @@ namespace Wander
                         {
                             var min = poly.mins[t];
                             var max = poly.maxs[t];
+
                             int x1 = Mathf.FloorToInt( min.x );
                             int y1 = Mathf.FloorToInt( min.y );
                             int x2 = Mathf.FloorToInt( max.x );
@@ -462,11 +465,14 @@ namespace Wander
                                     if (PointInTriangle( new Vector2( xk2, yk2 ), poly.vertices[i], poly.vertices[i+1], poly.vertices[i+2] ))
                                     {
                                         var addr2 = (resolution - y -1)*resolution+x;
-                                        //var addr2 = (resolution* y)+x;
-                                        if (layerIdx > 15) 
-                                            layerIdx = 15; // max layers 15 (15 is reserved, nothing was hit). 
-                                        var shift2 = (addr2&1) << 2;
-                                        texture[addr2>>1] |= (byte)(layerIdx << shift2);
+                                        if (!written[addr2])
+                                        {
+                                            written[addr2]=true;
+                                            if (layerIdx > 15)
+                                                layerIdx = 15; // max layers 15 (15 is reserved, nothing was hit).
+                                            var shift2 = (addr2&1) << 2;
+                                            texture[addr2>>1] |= (byte)(layerIdx << shift2);
+                                        }
                                     }
                                 }
                             }
@@ -600,8 +606,9 @@ namespace Wander
                 {
                     if ((x&1) == 0)
                         pixel = texture[addr>>1];
+                    UnityEngine.Debug.Assert( (pixel&0xF) < 10 && ((pixel>>4)&0xF) < 10 );
                     byte shift  = (byte)((addr&1));
-                    byte pixel2 = (byte)((pixel >> (shift<<2)) & 15);
+                    byte pixel2 = (byte)((pixel >> (shift<<2)) & 0xF);
                     if (pixel2 != 15)
                     {
                         if (pixel2 != cachedPixel)