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
13constexpr SkBlendMode gModes[] = {
14    SkBlendMode::kClear,
15    SkBlendMode::kSrc,
16    SkBlendMode::kDst,
17    SkBlendMode::kSrcOver,
18    SkBlendMode::kDstOver,
19    SkBlendMode::kSrcIn,
20    SkBlendMode::kDstIn,
21    SkBlendMode::kSrcOut,
22    SkBlendMode::kDstOut,
23    SkBlendMode::kSrcATop,
24    SkBlendMode::kDstATop,
25    SkBlendMode::kXor,
26};
27
28const int gWidth = 64;
29const int gHeight = 64;
30const SkScalar W = SkIntToScalar(gWidth);
31const SkScalar H = SkIntToScalar(gHeight);
32
33static SkScalar drawCell(SkCanvas* canvas, SkBlendMode mode, SkAlpha a0, SkAlpha a1) {
34
35    SkPaint paint;
36    paint.setAntiAlias(true);
37
38    SkRect r = SkRect::MakeWH(W, H);
39    r.inset(W/10, H/10);
40
41    paint.setColor(SK_ColorBLUE);
42    paint.setAlpha(a0);
43    canvas->drawOval(r, paint);
44
45    paint.setColor(SK_ColorRED);
46    paint.setAlpha(a1);
47    paint.setBlendMode(mode);
48    for (int angle = 0; angle < 24; ++angle) {
49        SkScalar x = SkScalarCos(SkIntToScalar(angle) * (SK_ScalarPI * 2) / 24) * gWidth;
50        SkScalar y = SkScalarSin(SkIntToScalar(angle) * (SK_ScalarPI * 2) / 24) * gHeight;
51        paint.setStrokeWidth(SK_Scalar1 * angle * 2 / 24);
52        canvas->drawLine(W/2, H/2, W/2 + x, H/2 + y, paint);
53    }
54
55    return H;
56}
57
58static sk_sp<SkShader> make_bg_shader() {
59    SkBitmap bm;
60    bm.allocN32Pixels(2, 2);
61    *bm.getAddr32(0, 0) = *bm.getAddr32(1, 1) = 0xFFFFFFFF;
62    *bm.getAddr32(1, 0) = *bm.getAddr32(0, 1) = SkPackARGB32(0xFF, 0xCE, 0xCF, 0xCE);
63
64    SkMatrix m;
65    m.setScale(SkIntToScalar(6), SkIntToScalar(6));
66    return SkShader::MakeBitmapShader(bm,
67                                      SkShader::kRepeat_TileMode, SkShader::kRepeat_TileMode, &m);
68}
69
70namespace skiagm {
71
72    class HairModesGM : public GM {
73        SkPaint fBGPaint;
74
75    protected:
76        SkString onShortName() override {
77            return SkString("hairmodes");
78        }
79
80        virtual SkISize onISize() override { return SkISize::Make(640, 480); }
81
82        void onOnceBeforeDraw() override {
83            fBGPaint.setShader(make_bg_shader());
84        }
85
86        void onDraw(SkCanvas* canvas) override {
87            const SkRect bounds = SkRect::MakeWH(W, H);
88            constexpr SkAlpha gAlphaValue[] = { 0xFF, 0x88, 0x88 };
89
90            canvas->translate(SkIntToScalar(4), SkIntToScalar(4));
91
92            for (int alpha = 0; alpha < 4; ++alpha) {
93                canvas->save();
94                canvas->save();
95                for (size_t i = 0; i < SK_ARRAY_COUNT(gModes); ++i) {
96                    if (6 == i) {
97                        canvas->restore();
98                        canvas->translate(W * 5, 0);
99                        canvas->save();
100                    }
101
102                    canvas->drawRect(bounds, fBGPaint);
103                    canvas->saveLayer(&bounds, nullptr);
104                    SkScalar dy = drawCell(canvas, gModes[i],
105                                           gAlphaValue[alpha & 1],
106                                           gAlphaValue[alpha & 2]);
107                    canvas->restore();
108
109                    canvas->translate(0, dy * 5 / 4);
110                }
111                canvas->restore();
112                canvas->restore();
113                canvas->translate(W * 5 / 4, 0);
114            }
115        }
116
117    private:
118        typedef GM INHERITED;
119    };
120
121    //////////////////////////////////////////////////////////////////////////////
122
123    static GM* MyFactory(void*) { return new HairModesGM; }
124    static GMRegistry reg(MyFactory);
125
126}
127