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 "gm.h"
9#include "SkCanvas.h"
10#include "SkColorPriv.h"
11#include "SkShader.h"
12
13static const struct {
14    SkXfermode::Mode  fMode;
15    const char*         fLabel;
16} gModes[] = {
17    { SkXfermode::kClear_Mode,    "Clear"     },
18    { SkXfermode::kSrc_Mode,      "Src"       },
19    { SkXfermode::kDst_Mode,      "Dst"       },
20    { SkXfermode::kSrcOver_Mode,  "SrcOver"   },
21    { SkXfermode::kDstOver_Mode,  "DstOver"   },
22    { SkXfermode::kSrcIn_Mode,    "SrcIn"     },
23    { SkXfermode::kDstIn_Mode,    "DstIn"     },
24    { SkXfermode::kSrcOut_Mode,   "SrcOut"    },
25    { SkXfermode::kDstOut_Mode,   "DstOut"    },
26    { SkXfermode::kSrcATop_Mode,  "SrcATop"   },
27    { SkXfermode::kDstATop_Mode,  "DstATop"   },
28    { SkXfermode::kXor_Mode,      "Xor"       },
29};
30
31const int gWidth = 64;
32const int gHeight = 64;
33const SkScalar W = SkIntToScalar(gWidth);
34const SkScalar H = SkIntToScalar(gHeight);
35
36static SkScalar drawCell(SkCanvas* canvas, SkXfermode* mode, SkAlpha a0, SkAlpha a1) {
37
38    SkPaint paint;
39    paint.setAntiAlias(true);
40
41    SkRect r = SkRect::MakeWH(W, H);
42    r.inset(W/10, H/10);
43
44    paint.setColor(SK_ColorBLUE);
45    paint.setAlpha(a0);
46    canvas->drawOval(r, paint);
47
48    paint.setColor(SK_ColorRED);
49    paint.setAlpha(a1);
50    paint.setXfermode(mode);
51    for (int angle = 0; angle < 24; ++angle) {
52        SkScalar x = SkScalarCos(SkIntToScalar(angle) * (SK_ScalarPI * 2) / 24) * gWidth;
53        SkScalar y = SkScalarSin(SkIntToScalar(angle) * (SK_ScalarPI * 2) / 24) * gHeight;
54        paint.setStrokeWidth(SK_Scalar1 * angle * 2 / 24);
55        canvas->drawLine(W/2, H/2, W/2 + x, H/2 + y, paint);
56    }
57
58    return H;
59}
60
61static SkShader* make_bg_shader() {
62    SkBitmap bm;
63    bm.allocN32Pixels(2, 2);
64    *bm.getAddr32(0, 0) = *bm.getAddr32(1, 1) = 0xFFFFFFFF;
65    *bm.getAddr32(1, 0) = *bm.getAddr32(0, 1) = SkPackARGB32(0xFF, 0xCC, 0xCC, 0xCC);
66
67    SkMatrix m;
68    m.setScale(SkIntToScalar(6), SkIntToScalar(6));
69    return SkShader::CreateBitmapShader(bm,
70                                        SkShader::kRepeat_TileMode,
71                                        SkShader::kRepeat_TileMode,
72                                        &m);
73}
74
75namespace skiagm {
76
77    class HairModesGM : public GM {
78        SkPaint fBGPaint;
79
80    protected:
81        virtual SkString onShortName() SK_OVERRIDE {
82            return SkString("hairmodes");
83        }
84
85        virtual SkISize onISize() { return SkISize::Make(640, 480); }
86
87        virtual void onOnceBeforeDraw() SK_OVERRIDE {
88            fBGPaint.setShader(make_bg_shader())->unref();
89        }
90
91        virtual void onDraw(SkCanvas* canvas) SK_OVERRIDE {
92            const SkRect bounds = SkRect::MakeWH(W, H);
93            static const SkAlpha gAlphaValue[] = { 0xFF, 0x88, 0x88 };
94
95            canvas->translate(SkIntToScalar(4), SkIntToScalar(4));
96
97            for (int alpha = 0; alpha < 4; ++alpha) {
98                canvas->save();
99                canvas->save();
100                for (size_t i = 0; i < SK_ARRAY_COUNT(gModes); ++i) {
101                    if (6 == i) {
102                        canvas->restore();
103                        canvas->translate(W * 5, 0);
104                        canvas->save();
105                    }
106                    SkXfermode* mode = SkXfermode::Create(gModes[i].fMode);
107
108                    canvas->drawRect(bounds, fBGPaint);
109                    canvas->saveLayer(&bounds, NULL);
110                    SkScalar dy = drawCell(canvas, mode,
111                                           gAlphaValue[alpha & 1],
112                                           gAlphaValue[alpha & 2]);
113                    canvas->restore();
114
115                    canvas->translate(0, dy * 5 / 4);
116                    SkSafeUnref(mode);
117                }
118                canvas->restore();
119                canvas->restore();
120                canvas->translate(W * 5 / 4, 0);
121            }
122        }
123
124        // disable pdf for now, since it crashes on mac
125        virtual uint32_t onGetFlags() const { return kSkipPDF_Flag | kSkipTiled_Flag; }
126
127    private:
128        typedef GM INHERITED;
129    };
130
131    //////////////////////////////////////////////////////////////////////////////
132
133    static GM* MyFactory(void*) { return new HairModesGM; }
134    static GMRegistry reg(MyFactory);
135
136}
137