1/*
2 * Copyright 2015 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 "SkAnimTimer.h"
10#include "SkDrawable.h"
11#include "SkView.h"
12#include "SkCanvas.h"
13#include "SkDrawable.h"
14#include "SkPath.h"
15#include "SkRandom.h"
16#include "SkRSXform.h"
17#include "SkString.h"
18#include "SkSurface.h"
19#include "SkGradientShader.h"
20
21const SkBlendMode gModes[] = {
22    SkBlendMode::kSrcOver,
23    SkBlendMode::kSrc,
24    SkBlendMode::kSrcIn,
25    SkBlendMode::kSrcOut,
26    SkBlendMode::kSrcATop,
27    SkBlendMode::kDstOver,
28    SkBlendMode::kDstIn,
29    SkBlendMode::kDstOut,
30    SkBlendMode::kDstATop,
31};
32const int N_Modes = SK_ARRAY_COUNT(gModes);
33
34static SkRandom gRand;
35
36struct ModeButton {
37    SkString fLabel;
38    SkColor  fColor;
39    SkRect   fRect;
40
41public:
42    void init(const char label[], const SkRect& rect) {
43        fLabel = label;
44        fRect = rect;
45        fColor = (gRand.nextU() & 0x7F7F7F7F) | SkColorSetARGB(0xFF, 0, 0, 0x80);
46    }
47
48    void draw(SkCanvas* canvas) {
49        SkPaint paint;
50        paint.setAntiAlias(true);
51        paint.setColor(fColor);
52        canvas->drawRoundRect(fRect, 8, 8, paint);
53
54        paint.setColor(0xFFFFFFFF);
55        paint.setTextSize(16);
56        paint.setTextAlign(SkPaint::kCenter_Align);
57        paint.setLCDRenderText(true);
58        canvas->drawString(fLabel, fRect.centerX(), fRect.fTop + 0.68f * fRect.height(), paint);
59    }
60
61    bool hitTest(SkScalar x, SkScalar y) {
62        return fRect.intersects(x - 1, y - 1, x + 1, y + 1);
63    }
64};
65
66class ModeDrawable : public SkDrawable {
67public:
68    ModeDrawable() : fMode(SkBlendMode::kSrcOver), fLoc(SkPoint::Make(0, 0)) {}
69
70    SkBlendMode fMode;
71    SkPoint     fLoc;
72
73    bool hitTest(SkScalar x, SkScalar y) {
74        SkRect target = SkRect::MakeXYWH(x - fLoc.x() - 1, y - fLoc.y() - 1, 3, 3);
75        return this->getBounds().intersects(target);
76    }
77};
78
79class CircDrawable : public ModeDrawable {
80    SkPaint fPaint;
81    SkRect  fBounds;
82
83public:
84    CircDrawable(SkScalar size, SkColor c) {
85        const SkColor colors[] = { 0, c };
86        fPaint.setShader(SkGradientShader::MakeRadial(SkPoint::Make(size/2, size/2), size/2,
87                                                                     colors, nullptr, 2,
88                                                                     SkShader::kClamp_TileMode));
89        fBounds = SkRect::MakeWH(size, size);
90    }
91
92protected:
93    SkRect onGetBounds() override {
94        return fBounds;
95    }
96
97    void onDraw(SkCanvas* canvas) override {
98        fPaint.setBlendMode(fMode);
99        canvas->save();
100        canvas->translate(fLoc.x(), fLoc.y());
101        canvas->drawOval(fBounds, fPaint);
102        canvas->restore();
103    }
104};
105
106class XferDemo : public SampleView {
107    enum {
108        N = 4
109    };
110
111    SkRect        fModeRect[N_Modes];
112    ModeButton    fModeButtons[N_Modes];
113    sk_sp<CircDrawable> fDrs[N];
114    CircDrawable* fSelected;
115
116    void addButtons() {
117        SkScalar x = 10;
118        SkScalar y = 10;
119        for (int i = 0; i < N_Modes; ++i) {
120            fModeButtons[i].init(SkBlendMode_Name(gModes[i]), SkRect::MakeXYWH(x, y, 70, 25));
121            fModeRect[i] = SkRect::MakeXYWH(x, y + 28, 70, 2);
122            x += 80;
123        }
124    }
125
126public:
127    XferDemo() {
128        const SkColor colors[] = { SK_ColorRED, SK_ColorGREEN, SK_ColorBLUE, SK_ColorBLACK };
129        for (int i = 0; i < N; ++i) {
130            fDrs[i].reset(new CircDrawable(200, colors[i]));
131            fDrs[i]->fLoc.set(100.f + i * 100, 100.f + i * 100);
132            fDrs[i]->fMode = SkBlendMode::kSrcOver;
133        }
134        fSelected = nullptr;
135
136        this->addButtons();
137    }
138
139protected:
140    bool onQuery(SkEvent* evt) override {
141        if (SampleCode::TitleQ(*evt)) {
142            SampleCode::TitleR(evt, "XferDemo");
143            return true;
144        }
145        return this->INHERITED::onQuery(evt);
146    }
147
148    void onDrawContent(SkCanvas* canvas) override {
149        for (int i = 0; i < N_Modes; ++i) {
150            fModeButtons[i].draw(canvas);
151        }
152
153        SkPaint paint;
154        if (fSelected) {
155            for (int i = 0; i < N_Modes; ++i) {
156                if (fSelected->fMode == gModes[i]) {
157                    canvas->drawRect(fModeRect[i], paint);
158                    break;
159                }
160            }
161        }
162
163        canvas->saveLayer(nullptr, nullptr);
164        for (int i = 0; i < N; ++i) {
165            fDrs[i]->draw(canvas);
166        }
167        canvas->restore();
168    }
169
170    SkView::Click* onFindClickHandler(SkScalar x, SkScalar y, unsigned) override {
171        // Check mode buttons first
172        for (int i = 0; i < N_Modes; ++i) {
173            if (fModeButtons[i].hitTest(x, y)) {
174                Click* click = new Click(this);
175                click->fMeta.setS32("mode", i);
176                return click;
177            }
178        }
179        fSelected = nullptr;
180        for (int i = N - 1; i >= 0; --i) {
181            if (fDrs[i]->hitTest(x, y)) {
182                fSelected = fDrs[i].get();
183                break;
184            }
185        }
186        return fSelected ? new Click(this) : nullptr;
187    }
188
189    bool onClick(Click* click) override {
190        int32_t mode;
191        if (click->fMeta.findS32("mode", &mode)) {
192            if (fSelected && Click::kUp_State == click->fState) {
193                fSelected->fMode = gModes[mode];
194            }
195        } else {
196            fSelected->fLoc.fX += click->fCurr.fX - click->fPrev.fX;
197            fSelected->fLoc.fY += click->fCurr.fY - click->fPrev.fY;
198        }
199        return true;
200    }
201
202private:
203    typedef SampleView INHERITED;
204};
205
206//////////////////////////////////////////////////////////////////////////////
207
208DEF_SAMPLE( return new XferDemo; )
209