xref: /third_party/skia/gm/xfermodes2.cpp (revision cb93a386) 
1/*
2 * Copyright 2013 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 "gm/gm.h"
9#include "include/core/SkBitmap.h"
10#include "include/core/SkBlendMode.h"
11#include "include/core/SkCanvas.h"
12#include "include/core/SkColor.h"
13#include "include/core/SkColorPriv.h"
14#include "include/core/SkFont.h"
15#include "include/core/SkMatrix.h"
16#include "include/core/SkPaint.h"
17#include "include/core/SkRect.h"
18#include "include/core/SkRefCnt.h"
19#include "include/core/SkScalar.h"
20#include "include/core/SkShader.h"
21#include "include/core/SkSize.h"
22#include "include/core/SkString.h"
23#include "include/core/SkTileMode.h"
24#include "include/core/SkTypeface.h"
25#include "include/utils/SkTextUtils.h"
26#include "tools/ToolUtils.h"
27#include <stdint.h>
28#include <string.h>
29
30namespace skiagm {
31
32class Xfermodes2GM : public GM {
33public:
34    Xfermodes2GM() {}
35
36protected:
37    SkString onShortName() override {
38        return SkString("xfermodes2");
39    }
40
41    SkISize onISize() override {
42        return SkISize::Make(455, 475);
43    }
44
45    void onDraw(SkCanvas* canvas) override {
46        canvas->translate(SkIntToScalar(10), SkIntToScalar(20));
47
48        const SkScalar w = SkIntToScalar(kSize);
49        const SkScalar h = SkIntToScalar(kSize);
50
51        SkFont font(ToolUtils::create_portable_typeface());
52
53        const int W = 6;
54
55        SkScalar x = 0, y = 0;
56        for (size_t m = 0; m <= (size_t)SkBlendMode::kLastMode; m++) {
57            SkBlendMode mode = static_cast<SkBlendMode>(m);
58
59            canvas->save();
60
61            canvas->translate(x, y);
62            SkPaint p;
63            p.setAntiAlias(false);
64            p.setStyle(SkPaint::kFill_Style);
65            p.setShader(fBG);
66            SkRect r = SkRect::MakeWH(w, h);
67            canvas->drawRect(r, p);
68
69            canvas->saveLayer(&r, nullptr);
70
71            p.setShader(fDst);
72            canvas->drawRect(r, p);
73            p.setShader(fSrc);
74            p.setBlendMode(mode);
75            canvas->drawRect(r, p);
76
77            canvas->restore();
78
79            r.inset(-SK_ScalarHalf, -SK_ScalarHalf);
80            p.setStyle(SkPaint::kStroke_Style);
81            p.setShader(nullptr);
82            p.setBlendMode(SkBlendMode::kSrcOver);
83            canvas->drawRect(r, p);
84
85            canvas->restore();
86
87#if 1
88            SkTextUtils::DrawString(canvas, SkBlendMode_Name(mode), x + w/2, y - font.getSize()/2, font, SkPaint(),
89                                    SkTextUtils::kCenter_Align);
90#endif
91            x += w + SkIntToScalar(10);
92            if ((m % W) == W - 1) {
93                x = 0;
94                y += h + SkIntToScalar(30);
95            }
96        }
97    }
98
99private:
100    void onOnceBeforeDraw() override {
101        const uint32_t kCheckData[] = {
102            SkPackARGB32(0xFF, 0x42, 0x41, 0x42),
103            SkPackARGB32(0xFF, 0xD6, 0xD3, 0xD6),
104            SkPackARGB32(0xFF, 0xD6, 0xD3, 0xD6),
105            SkPackARGB32(0xFF, 0x42, 0x41, 0x42)
106        };
107        SkBitmap bg;
108        bg.allocN32Pixels(2, 2, true);
109        memcpy(bg.getPixels(), kCheckData, sizeof(kCheckData));
110
111        SkMatrix lm;
112        lm.setScale(SkIntToScalar(16), SkIntToScalar(16));
113        fBG = bg.makeShader(SkTileMode::kRepeat, SkTileMode::kRepeat, SkSamplingOptions(), lm);
114
115        SkBitmap srcBmp;
116        srcBmp.allocN32Pixels(kSize, kSize);
117        SkPMColor* pixels = reinterpret_cast<SkPMColor*>(srcBmp.getPixels());
118
119        for (int y = 0; y < kSize; ++y) {
120            int c = y * (1 << kShift);
121            SkPMColor rowColor = SkPackARGB32(c, c, 0, c/2);
122            for (int x = 0; x < kSize; ++x) {
123                pixels[kSize * y + x] = rowColor;
124            }
125        }
126        fSrc = srcBmp.makeShader(SkSamplingOptions());
127        SkBitmap dstBmp;
128        dstBmp.allocN32Pixels(kSize, kSize);
129        pixels = reinterpret_cast<SkPMColor*>(dstBmp.getPixels());
130
131        for (int x = 0; x < kSize; ++x) {
132            int c = x * (1 << kShift);
133            SkPMColor colColor = SkPackARGB32(c, 0, c, c/2);
134            for (int y = 0; y < kSize; ++y) {
135                pixels[kSize * y + x] = colColor;
136            }
137        }
138        fDst = dstBmp.makeShader(SkSamplingOptions());
139    }
140
141    enum {
142        kShift = 2,
143        kSize = 256 >> kShift,
144    };
145
146    sk_sp<SkShader> fBG;
147    sk_sp<SkShader> fSrc;
148    sk_sp<SkShader> fDst;
149
150    using INHERITED = GM;
151};
152
153//////////////////////////////////////////////////////////////////////////////
154
155DEF_GM( return new Xfermodes2GM; )
156
157}  // namespace skiagm
158