1/*
2 * Copyright 2011 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 "SampleCode.h"
9#include "SkView.h"
10#include "SkCanvas.h"
11#include "SkDevice.h"
12#include "SkColorPriv.h"
13#include "SkShader.h"
14
15static SkCanvas* create_canvas(int w, int h) {
16    SkBitmap bm;
17    bm.setConfig(SkBitmap::kARGB_8888_Config, w, h);
18    bm.allocPixels();
19    bm.eraseColor(0);
20    return new SkCanvas(bm);
21}
22
23static const SkBitmap& extract_bitmap(SkCanvas* canvas) {
24    return canvas->getDevice()->accessBitmap(false);
25}
26
27static const struct {
28    SkXfermode::Mode  fMode;
29    const char*         fLabel;
30} gModes[] = {
31    { SkXfermode::kClear_Mode,    "Clear"     },
32    { SkXfermode::kSrc_Mode,      "Src"       },
33    { SkXfermode::kDst_Mode,      "Dst"       },
34    { SkXfermode::kSrcOver_Mode,  "SrcOver"   },
35    { SkXfermode::kDstOver_Mode,  "DstOver"   },
36    { SkXfermode::kSrcIn_Mode,    "SrcIn"     },
37    { SkXfermode::kDstIn_Mode,    "DstIn"     },
38    { SkXfermode::kSrcOut_Mode,   "SrcOut"    },
39    { SkXfermode::kDstOut_Mode,   "DstOut"    },
40    { SkXfermode::kSrcATop_Mode,  "SrcATop"   },
41    { SkXfermode::kDstATop_Mode,  "DstATop"   },
42    { SkXfermode::kXor_Mode,      "Xor"       },
43};
44
45const int gWidth = 64;
46const int gHeight = 64;
47const SkScalar W = SkIntToScalar(gWidth);
48const SkScalar H = SkIntToScalar(gHeight);
49
50static SkScalar drawCell(SkCanvas* canvas, SkXfermode* mode,
51                         SkAlpha a0, SkAlpha a1) {
52
53    SkPaint paint;
54    paint.setAntiAlias(true);
55
56    SkRect r = SkRect::MakeWH(W, H);
57    r.inset(W/10, H/10);
58
59    paint.setColor(SK_ColorBLUE);
60    paint.setAlpha(a0);
61    canvas->drawOval(r, paint);
62
63    paint.setColor(SK_ColorRED);
64    paint.setAlpha(a1);
65    paint.setXfermode(mode);
66
67    SkScalar offset = SK_Scalar1 / 3;
68    SkRect rect = SkRect::MakeXYWH(W / 4 + offset,
69                                   H / 4 + offset,
70                                   W / 2, H / 2);
71    canvas->drawRect(rect, paint);
72
73    return H;
74}
75
76static SkShader* make_bg_shader() {
77    SkBitmap bm;
78    bm.setConfig(SkBitmap::kARGB_8888_Config, 2, 2);
79    bm.allocPixels();
80    *bm.getAddr32(0, 0) = *bm.getAddr32(1, 1) = 0xFFFFFFFF;
81    *bm.getAddr32(1, 0) = *bm.getAddr32(0, 1) = SkPackARGB32(0xFF, 0xCC,
82                                                             0xCC, 0xCC);
83
84    SkShader* s = SkShader::CreateBitmapShader(bm,
85                                               SkShader::kRepeat_TileMode,
86                                               SkShader::kRepeat_TileMode);
87
88    SkMatrix m;
89    m.setScale(SkIntToScalar(6), SkIntToScalar(6));
90    s->setLocalMatrix(m);
91    return s;
92}
93
94class AARectsModesView : public SampleView {
95    SkPaint fBGPaint;
96public:
97    AARectsModesView () {
98        fBGPaint.setShader(make_bg_shader())->unref();
99    }
100
101protected:
102    // overrides from SkEventSink
103    virtual bool onQuery(SkEvent* evt) {
104        if (SampleCode::TitleQ(*evt)) {
105            SampleCode::TitleR(evt, "AARectsModes");
106            return true;
107        }
108        return this->INHERITED::onQuery(evt);
109    }
110
111    virtual void onDrawContent(SkCanvas* canvas) {
112        const SkRect bounds = SkRect::MakeWH(W, H);
113        static const SkAlpha gAlphaValue[] = { 0xFF, 0x88, 0x88 };
114
115        canvas->translate(SkIntToScalar(4), SkIntToScalar(4));
116
117        for (int alpha = 0; alpha < 4; ++alpha) {
118            canvas->save();
119            canvas->save();
120            for (size_t i = 0; i < SK_ARRAY_COUNT(gModes); ++i) {
121                if (6 == i) {
122                    canvas->restore();
123                    canvas->translate(W * 5, 0);
124                    canvas->save();
125                }
126                SkXfermode* mode = SkXfermode::Create(gModes[i].fMode);
127
128                canvas->drawRect(bounds, fBGPaint);
129                canvas->saveLayer(&bounds, NULL);
130                SkScalar dy = drawCell(canvas, mode,
131                                       gAlphaValue[alpha & 1],
132                                       gAlphaValue[alpha & 2]);
133                canvas->restore();
134
135                canvas->translate(0, dy * 5 / 4);
136                SkSafeUnref(mode);
137            }
138            canvas->restore();
139            canvas->restore();
140            canvas->translate(W * 5 / 4, 0);
141        }
142    }
143
144private:
145    typedef SampleView INHERITED;
146};
147
148///////////////////////////////////////////////////////////////////////////////
149
150static SkView* MyFactory() { return new AARectsModesView; }
151static SkViewRegister reg(MyFactory);
152
153