Tessellator: stop copying vertices into Polys and Monotones.

gm/concavepaths.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "gm.h"
 #include "SkCanvas.h"
 #include "SkPath.h"
@@ skipping 148 matching lines @@
     canvas->save();
     canvas->translate(200, 200);
     path.moveTo(SkIntToScalar(20), SkIntToScalar(80));
     path.lineTo(SkIntToScalar(80), SkIntToScalar(80));
     path.lineTo(SkIntToScalar(80), SkIntToScalar(20));
     path.lineTo(SkIntToScalar(80), SkIntToScalar(30));
     canvas->drawPath(path, paint);
     canvas->restore();
 }
 
+// Two "island" triangles inside a containing rect.
+// This exercises the partnering code in the tessellator.
+void test_partners(SkCanvas* canvas, const SkPaint& paint) {
+    SkPath path;
+    canvas->save();
+    canvas->translate(300, 200);
+    path.moveTo(20, 80);
+    path.lineTo(80, 80);
+    path.lineTo(80, 20);
+    path.lineTo(20, 20);
+    path.moveTo(30, 30);
+    path.lineTo(45, 50);
+    path.lineTo(30, 70);
+    path.moveTo(70, 30);
+    path.lineTo(70, 70);
+    path.lineTo(55, 50);
+    canvas->drawPath(path, paint);
+    canvas->restore();
+}
+
 // Monotone test 1 (point in the middle)
 void test_monotone_1(SkCanvas* canvas, const SkPaint& paint) {
     SkPath path;
     canvas->save();
     canvas->translate(0, 300);
     path.moveTo(SkIntToScalar(20), SkIntToScalar(20));
     path.quadTo(SkIntToScalar(20), SkIntToScalar(50),
                 SkIntToScalar(80), SkIntToScalar(50));
     path.quadTo(SkIntToScalar(20), SkIntToScalar(50),
                 SkIntToScalar(20), SkIntToScalar(80));
@@ skipping 184 matching lines @@
         test_reverse_concave(canvas, paint);
         test_bowtie(canvas, paint);
         test_fake_bowtie(canvas, paint);
         test_fish(canvas, paint);
         test_collinear_edges(canvas, paint);
         test_hole(canvas, paint);
         test_star(canvas, paint);
         test_stairstep(canvas, paint);
         test_stairstep2(canvas, paint);
         test_overlapping(canvas, paint);
+        test_partners(canvas, paint);
         test_monotone_1(canvas, paint);
         test_monotone_2(canvas, paint);
         test_monotone_3(canvas, paint);
         test_monotone_4(canvas, paint);
         test_monotone_5(canvas, paint);
         test_degenerate(canvas, paint);
         test_coincident_edge(canvas, paint);
         test_bowtie_coincident_triangle(canvas, paint);
         test_coincident_edges_1(canvas, paint);
         test_coincident_edges_2(canvas, paint);
         test_coincident_edges_3(canvas, paint);
         test_coincident_edges_4(canvas, paint);
     }
 
 private:
     typedef skiagm::GM INHERITED;
 };
 
 DEF_GM( return new ConcavePathsGM; )