1
2/*
3 * Copyright 2013 Google Inc.
4 *
5 * Use of this source code is governed by a BSD-style license that can be
6 * found in the LICENSE file.
7 */
8#include "gm.h"
9#include "SkBitmap.h"
10#include "SkShader.h"
11#include "SkXfermode.h"
12#include "SkColorPriv.h"
13
14namespace skiagm {
15
16class Xfermodes2GM : public GM {
17public:
18    Xfermodes2GM() {}
19
20protected:
21    SkString onShortName() override {
22        return SkString("xfermodes2");
23    }
24
25    SkISize onISize() override {
26        return SkISize::Make(455, 475);
27    }
28
29    void onDraw(SkCanvas* canvas) override {
30        canvas->translate(SkIntToScalar(10), SkIntToScalar(20));
31
32        const SkScalar w = SkIntToScalar(kSize);
33        const SkScalar h = SkIntToScalar(kSize);
34
35        SkPaint labelP;
36        labelP.setAntiAlias(true);
37        sk_tool_utils::set_portable_typeface(&labelP);
38        labelP.setTextAlign(SkPaint::kCenter_Align);
39
40        const int W = 6;
41
42        SkScalar x = 0, y = 0;
43        for (size_t m = 0; m <= SkXfermode::kLastMode; m++) {
44            SkXfermode::Mode mode = static_cast<SkXfermode::Mode>(m);
45            SkXfermode* xm = SkXfermode::Create(mode);
46            SkAutoUnref aur(xm);
47
48            canvas->save();
49
50            canvas->translate(x, y);
51            SkPaint p;
52            p.setAntiAlias(false);
53            p.setStyle(SkPaint::kFill_Style);
54            p.setShader(fBG);
55            SkRect r = SkRect::MakeWH(w, h);
56            canvas->drawRect(r, p);
57
58            canvas->saveLayer(&r, nullptr);
59
60            p.setShader(fDst);
61            canvas->drawRect(r, p);
62            p.setShader(fSrc);
63            p.setXfermode(xm);
64            canvas->drawRect(r, p);
65
66            canvas->restore();
67
68            r.inset(-SK_ScalarHalf, -SK_ScalarHalf);
69            p.setStyle(SkPaint::kStroke_Style);
70            p.setShader(nullptr);
71            p.setXfermode(nullptr);
72            canvas->drawRect(r, p);
73
74            canvas->restore();
75
76#if 1
77            canvas->drawText(SkXfermode::ModeName(mode), strlen(SkXfermode::ModeName(mode)),
78                             x + w/2, y - labelP.getTextSize()/2, labelP);
79#endif
80            x += w + SkIntToScalar(10);
81            if ((m % W) == W - 1) {
82                x = 0;
83                y += h + SkIntToScalar(30);
84            }
85        }
86    }
87
88private:
89    void onOnceBeforeDraw() override {
90        static const uint32_t kCheckData[] = {
91            SkPackARGB32(0xFF, 0x42, 0x41, 0x42),
92            SkPackARGB32(0xFF, 0xD6, 0xD3, 0xD6),
93            SkPackARGB32(0xFF, 0xD6, 0xD3, 0xD6),
94            SkPackARGB32(0xFF, 0x42, 0x41, 0x42)
95        };
96        SkBitmap bg;
97        bg.allocN32Pixels(2, 2, true);
98        memcpy(bg.getPixels(), kCheckData, sizeof(kCheckData));
99
100        SkMatrix lm;
101        lm.setScale(SkIntToScalar(16), SkIntToScalar(16));
102        fBG.reset(SkShader::CreateBitmapShader(bg,
103                                               SkShader::kRepeat_TileMode,
104                                               SkShader::kRepeat_TileMode,
105                                               &lm));
106
107        SkBitmap srcBmp;
108        srcBmp.allocN32Pixels(kSize, kSize);
109        SkPMColor* pixels = reinterpret_cast<SkPMColor*>(srcBmp.getPixels());
110
111        for (int y = 0; y < kSize; ++y) {
112            int c = y * (1 << kShift);
113            SkPMColor rowColor = SkPackARGB32(c, c, 0, c/2);
114            for (int x = 0; x < kSize; ++x) {
115                pixels[kSize * y + x] = rowColor;
116            }
117        }
118        fSrc.reset(SkShader::CreateBitmapShader(srcBmp,
119                                                SkShader::kClamp_TileMode,
120                                                SkShader::kClamp_TileMode));
121        SkBitmap dstBmp;
122        dstBmp.allocN32Pixels(kSize, kSize);
123        pixels = reinterpret_cast<SkPMColor*>(dstBmp.getPixels());
124
125        for (int x = 0; x < kSize; ++x) {
126            int c = x * (1 << kShift);
127            SkPMColor colColor = SkPackARGB32(c, 0, c, c/2);
128            for (int y = 0; y < kSize; ++y) {
129                pixels[kSize * y + x] = colColor;
130            }
131        }
132        fDst.reset(SkShader::CreateBitmapShader(dstBmp,
133                                                SkShader::kClamp_TileMode,
134                                                SkShader::kClamp_TileMode));
135    }
136
137    enum {
138        kShift = 2,
139        kSize = 256 >> kShift,
140    };
141
142    SkAutoTUnref<SkShader> fBG;
143    SkAutoTUnref<SkShader> fSrc;
144    SkAutoTUnref<SkShader> fDst;
145
146    typedef GM INHERITED;
147};
148
149//////////////////////////////////////////////////////////////////////////////
150
151static GM* MyFactory(void*) { return new Xfermodes2GM; }
152static GMRegistry reg(MyFactory);
153
154}
155