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