1
2/*
3 * Copyright 2011 Google Inc.
4 *
5 * Use of this source code is governed by a BSD-style license that can be
6 * found in the LICENSE file.
7 */
8#include "SampleCode.h"
9#include "SkView.h"
10#include "SkCanvas.h"
11#include "SkGradientShader.h"
12#include "SkAvoidXfermode.h"
13
14///////////////////////////////////////////////////////////////////////////////
15
16class AvoidView : public SampleView {
17    SkShader* fShader;
18
19    enum {
20        W = 480,
21        H = 320
22    };
23public:
24    AvoidView() {
25        SkColor colors[] = { SK_ColorRED, SK_ColorYELLOW, SK_ColorGREEN, SK_ColorCYAN, SK_ColorBLUE };
26
27#if 0
28        SkPoint pts[] = { 0, 0, SkIntToScalar(100), SkIntToScalar(100) };
29        fShader = SkGradientShader::CreateLinear(pts, colors, NULL,
30                                                 SK_ARRAY_COUNT(colors),
31                                                 SkShader::kMirror_TileMode);
32#else
33        SkPoint pts[] = { { SkIntToScalar(W)/2, SkIntToScalar(H)/2 } };
34        fShader = SkGradientShader::CreateRadial(pts[0], SkIntToScalar(H)/5,
35                                                 colors, NULL,
36                                                 SK_ARRAY_COUNT(colors),
37                                                 SkShader::kMirror_TileMode);
38#endif
39    }
40
41    virtual ~AvoidView() {
42        fShader->unref();
43    }
44
45protected:
46    virtual bool onQuery(SkEvent* evt) {
47        if (SampleCode::TitleQ(*evt)) {
48            SampleCode::TitleR(evt, "AvoidXfermode");
49            return true;
50        }
51        return this->INHERITED::onQuery(evt);
52    }
53
54    virtual void onDrawContent(SkCanvas* canvas) {
55        SkPaint paint;
56        SkRect r = { 0, 0, SkIntToScalar(W), SkIntToScalar(H) };
57
58        canvas->translate(r.width() / 6, r.height() / 6);
59
60        paint.setShader(fShader);
61        canvas->drawRect(r, paint);
62
63        static const struct {
64            int                     fTolerance;
65            SkAvoidXfermode::Mode   fMode;
66            float                   fDX, fDY;
67        } gData[] = {
68            { 16,       SkAvoidXfermode::kAvoidColor_Mode, 0, 0 },
69            { 255-16,   SkAvoidXfermode::kAvoidColor_Mode, 1, 0 },
70            { 16,       SkAvoidXfermode::kTargetColor_Mode, 0, 1 },
71            { 255-16,   SkAvoidXfermode::kTargetColor_Mode, 1, 1 },
72        };
73
74        paint.setShader(NULL);
75        paint.setColor(SK_ColorMAGENTA);
76
77        SkPaint frameP;
78        frameP.setStyle(SkPaint::kStroke_Style);
79
80        for (size_t i = 0; i < SK_ARRAY_COUNT(gData); i++) {
81            SkAutoTUnref<SkAvoidXfermode> mode(SkAvoidXfermode::Create(
82                SK_ColorGREEN, gData[i].fTolerance, gData[i].fMode));
83            paint.setXfermode(mode);
84            int div = 3;
85            SkRect rr = { 0, 0, r.width()/div, r.height()/div };
86            rr.offset(r.width()/4 - rr.width()/2, r.height()/4 - rr.height()/2);
87            rr.offset(r.width() * gData[i].fDX/2, r.height() * gData[i].fDY/2);
88            canvas->drawRect(rr, paint);
89            paint.setXfermode(NULL);
90
91            canvas->drawRect(rr, frameP);
92        }
93    }
94
95private:
96    typedef SampleView INHERITED;
97};
98
99//////////////////////////////////////////////////////////////////////////////
100
101static SkView* MyFactory() {
102    return new AvoidView;
103}
104
105static SkViewRegister reg(MyFactory);
106