2 * Copyright 2015 Google Inc.
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
9 #include "include/core/SkBlendMode.h"
10 #include "include/core/SkCanvas.h"
11 #include "include/core/SkColor.h"
12 #include "include/core/SkPaint.h"
13 #include "include/core/SkPath.h"
14 #include "include/core/SkRect.h"
16 DEF_SIMPLE_GM(PlusMergesAA, canvas, 256, 256) {
18 p.setColor(SK_ColorRED);
19 p.setAntiAlias(true); // <-- crucial to the test that we use AA
21 // Draw a two red squares.
22 canvas->drawRect(SkRect::MakeWH(100, 100), p);
23 canvas->drawRect(SkRect::MakeXYWH(150, 0, 100, 100), p);
25 p.setColor(0xf000ff00);
27 // We'll draw a green square on top of each using two triangles.
29 upperLeft.lineTo(100, 0);
30 upperLeft.lineTo(0, 100);
31 upperLeft.lineTo(0, 0);
34 bottomRight.moveTo(100, 0);
35 bottomRight.lineTo(100, 100);
36 bottomRight.lineTo(0, 100);
37 bottomRight.lineTo(100, 0);
39 // The left square is drawn simply with SrcOver. It will show a red seam.
40 canvas->drawPath(upperLeft, p);
41 canvas->drawPath(bottomRight, p);
43 // Using Plus on the right should merge the AA of seam together completely covering the red.
44 canvas->saveLayer(nullptr, nullptr);
45 p.setBlendMode(SkBlendMode::kPlus);
46 canvas->translate(150, 0);
47 canvas->drawPath(upperLeft, p);
48 canvas->drawPath(bottomRight, p);