1/*
2 * Copyright 2014 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8#include "Test.h"
9
10#include "../include/core/SkCanvas.h"
11#include "../include/core/SkPicture.h"
12#include "../include/core/SkStream.h"
13#include "../include/core/SkString.h"
14#include "../include/core/SkPictureRecorder.h"
15#include <cstring>
16
17// Verify that replay of a recording into a clipped canvas
18// produces the correct bitmap.
19// This arose from http://crbug.com/401593 which has
20// https://code.google.com/p/skia/issues/detail?id=1291 as its root cause.
21
22namespace {
23
24class Drawer {
25 public:
26    explicit Drawer() : fImageInfo(SkImageInfo::MakeN32Premul(200, 100)) {
27        fCircleBM.allocPixels(SkImageInfo::MakeN32Premul(100, 100));
28        SkCanvas canvas(fCircleBM);
29        canvas.clear(0xffffffff);
30        SkPaint circlePaint;
31        circlePaint.setColor(0xff000000);
32        canvas.drawCircle(50, 50, 50, circlePaint);
33    }
34
35    const SkImageInfo& imageInfo() const { return fImageInfo; }
36
37    void draw(SkCanvas* canvas, const SkRect& clipRect, SkXfermode::Mode mode) const {
38        SkPaint greenPaint;
39        greenPaint.setColor(0xff008000);
40        SkPaint blackPaint;
41        blackPaint.setColor(0xff000000);
42        SkPaint whitePaint;
43        whitePaint.setColor(0xffffffff);
44        SkPaint layerPaint;
45        layerPaint.setColor(0xff000000);
46        layerPaint.setXfermodeMode(mode);
47        SkRect canvasRect(SkRect::MakeWH(SkIntToScalar(fImageInfo.width()),
48                                         SkIntToScalar(fImageInfo.height())));
49
50        canvas->clipRect(clipRect);
51        canvas->clear(0xff000000);
52
53        canvas->saveLayer(nullptr, &blackPaint);
54            canvas->drawRect(canvasRect, greenPaint);
55            canvas->saveLayer(nullptr, &layerPaint);
56                canvas->drawBitmapRect(fCircleBM, SkRect::MakeXYWH(20,20,60,60), &blackPaint);
57            canvas->restore();
58        canvas->restore();
59    }
60
61 private:
62    const SkImageInfo fImageInfo;
63    SkBitmap fCircleBM;
64};
65
66class RecordingStrategy {
67 public:
68    virtual ~RecordingStrategy() {}
69    virtual const SkBitmap& recordAndReplay(const Drawer& drawer,
70                                            const SkRect& intoClip,
71                                            SkXfermode::Mode) = 0;
72};
73
74class BitmapBackedCanvasStrategy : public RecordingStrategy {
75    // This version just draws into a bitmap-backed canvas.
76 public:
77    BitmapBackedCanvasStrategy(const SkImageInfo& imageInfo) {
78        fBitmap.allocPixels(imageInfo);
79    }
80
81    virtual const SkBitmap& recordAndReplay(const Drawer& drawer,
82                                            const SkRect& intoClip,
83                                            SkXfermode::Mode mode) {
84        SkCanvas canvas(fBitmap);
85        canvas.clear(0xffffffff);
86        // Note that the scene is drawn just into the clipped region!
87        canvas.clipRect(intoClip);
88        drawer.draw(&canvas, intoClip, mode); // Shouild be canvas-wide...
89        return fBitmap;
90    }
91
92 private:
93    SkBitmap fBitmap;
94};
95
96class PictureStrategy : public RecordingStrategy {
97    // This version draws the entire scene into an SkPictureRecorder.
98    // Then it then replays the scene through a clip rectangle.
99    // This backend proved to be buggy.
100 public:
101    PictureStrategy(const SkImageInfo& imageInfo) {
102        fBitmap.allocPixels(imageInfo);
103        fWidth  = imageInfo.width();
104        fHeight = imageInfo.height();
105    }
106
107    virtual const SkBitmap& recordAndReplay(const Drawer& drawer,
108                                            const SkRect& intoClip,
109                                            SkXfermode::Mode mode) {
110        SkRTreeFactory factory;
111        SkPictureRecorder recorder;
112        SkRect canvasRect(SkRect::MakeWH(SkIntToScalar(fWidth),SkIntToScalar(fHeight)));
113        SkCanvas* canvas = recorder.beginRecording(SkIntToScalar(fWidth),
114                                                   SkIntToScalar(fHeight),
115                                                   &factory);
116        drawer.draw(canvas, canvasRect, mode);
117        SkAutoTUnref<SkPicture> picture(recorder.endRecording());
118
119        SkCanvas replayCanvas(fBitmap);
120        replayCanvas.clear(0xffffffff);
121        replayCanvas.clipRect(intoClip);
122        picture->playback(&replayCanvas);
123        return fBitmap;
124    }
125
126 private:
127    SkBitmap fBitmap;
128    int fWidth;
129    int fHeight;
130};
131
132} // namespace
133
134
135DEF_TEST(SkRecordingAccuracyXfermode, reporter) {
136#define FINEGRAIN 0
137    const Drawer drawer;
138
139    BitmapBackedCanvasStrategy golden(drawer.imageInfo());
140    PictureStrategy picture(drawer.imageInfo());
141
142#if !FINEGRAIN
143    unsigned numErrors = 0;
144    SkString errors;
145#endif
146
147    for (int iMode = 0; iMode < int(SkXfermode::kLastMode); iMode++) {
148        const SkRect& clip = SkRect::MakeXYWH(100, 0, 100, 100);
149        SkXfermode::Mode mode = SkXfermode::Mode(iMode);
150
151        const SkBitmap& goldenBM = golden.recordAndReplay(drawer, clip, mode);
152        const SkBitmap& pictureBM = picture.recordAndReplay(drawer, clip, mode);
153
154        size_t pixelsSize = goldenBM.getSize();
155        REPORTER_ASSERT(reporter, pixelsSize == pictureBM.getSize());
156
157        // The pixel arrays should match.
158#if FINEGRAIN
159        REPORTER_ASSERT(reporter,
160                        0 == memcmp(goldenBM.getPixels(), pictureBM.getPixels(), pixelsSize));
161#else
162        if (memcmp(goldenBM.getPixels(), pictureBM.getPixels(), pixelsSize)) {
163            numErrors++;
164            errors.appendf("For SkXfermode %d %s:    SkPictureRecorder bitmap is wrong\n",
165                           iMode, SkXfermode::ModeName(mode));
166        }
167#endif
168    }
169
170#if !FINEGRAIN
171    REPORTER_ASSERT_MESSAGE(reporter, 0 == numErrors, errors.c_str());
172#endif
173}
174