SampleMipMap.cpp revision 0b15698a8c76bb8abc1b555c1d91892669b4118f 
1#include "SampleCode.h"
2#include "SkView.h"
3#include "SkCanvas.h"
4#include "SkDevice.h"
5#include "SkPaint.h"
6#include "SkShader.h"
7
8static SkBitmap createBitmap(int n) {
9    SkBitmap bitmap;
10    bitmap.setConfig(SkBitmap::kARGB_8888_Config, n, n);
11    bitmap.allocPixels();
12    bitmap.eraseColor(0);
13
14    SkCanvas canvas(bitmap);
15    SkRect r;
16    r.set(0, 0, SkIntToScalar(n), SkIntToScalar(n));
17    SkPaint paint;
18    paint.setAntiAlias(true);
19
20    paint.setColor(SK_ColorRED);
21    canvas.drawOval(r, paint);
22    paint.setColor(SK_ColorBLUE);
23    paint.setStrokeWidth(SkIntToScalar(n)/15);
24    paint.setStyle(SkPaint::kStroke_Style);
25    canvas.drawLine(0, 0, r.fRight, r.fBottom, paint);
26    canvas.drawLine(0, r.fBottom, r.fRight, 0, paint);
27
28    return bitmap;
29}
30
31class MipMapView : public SampleView {
32    SkBitmap fBitmap;
33    enum {
34        N = 64
35    };
36public:
37    MipMapView() {
38        fBitmap = createBitmap(N);
39
40        fWidth = N;
41    }
42
43protected:
44    // overrides from SkEventSink
45    virtual bool onQuery(SkEvent* evt) {
46        if (SampleCode::TitleQ(*evt)) {
47            SampleCode::TitleR(evt, "MipMaps");
48            return true;
49        }
50        return this->INHERITED::onQuery(evt);
51    }
52
53    void drawN(SkCanvas* canvas, const SkBitmap& bitmap) {
54        SkAutoCanvasRestore acr(canvas, true);
55        for (int i = N; i > 1; i >>= 1) {
56            canvas->drawBitmap(bitmap, 0, 0, NULL);
57            canvas->translate(SkIntToScalar(N + 8), 0);
58            canvas->scale(SK_ScalarHalf, SK_ScalarHalf);
59        }
60    }
61
62    void drawN2(SkCanvas* canvas, const SkBitmap& bitmap) {
63        SkBitmap bg;
64        bg.setConfig(SkBitmap::kARGB_8888_Config, N, N);
65        bg.allocPixels();
66
67        SkAutoCanvasRestore acr(canvas, true);
68        for (int i = 0; i < 6; i++) {
69            bg.eraseColor(0);
70            SkCanvas c(bg);
71            c.scale(SK_Scalar1 / (1 << i), SK_Scalar1 / (1 << i));
72            c.drawBitmap(bitmap, 0, 0, NULL);
73
74            canvas->save();
75            canvas->scale(SkIntToScalar(1 << i), SkIntToScalar(1 << i));
76            canvas->drawBitmap(bg, 0, 0, NULL);
77            canvas->restore();
78            canvas->translate(SkIntToScalar(N + 8), 0);
79        }
80    }
81
82    virtual void onDrawContent(SkCanvas* canvas) {
83        canvas->translate(SkIntToScalar(10), SkIntToScalar(10));
84
85        canvas->scale(1.00000001f, 0.9999999f);
86
87        drawN2(canvas, fBitmap);
88
89        canvas->translate(0, SkIntToScalar(N + 8));
90        SkBitmap bitmap(fBitmap);
91        bitmap.buildMipMap();
92        drawN2(canvas, bitmap);
93
94        SkScalar time = SampleCode::GetAnimScalar(SkIntToScalar(1)/4,
95                                                  SkIntToScalar(2));
96        if (time >= SK_Scalar1) {
97            time = SkIntToScalar(2) - time;
98        }
99        fWidth = 8 + SkScalarRound(N * time);
100
101        SkRect dst;
102        dst.set(0, 0, SkIntToScalar(fWidth), SkIntToScalar(fWidth));
103
104        SkPaint paint;
105        paint.setFilterBitmap(true);
106        paint.setAntiAlias(true);
107
108        canvas->translate(0, SkIntToScalar(N + 8));
109        canvas->drawBitmapRect(fBitmap, NULL, dst, NULL);
110        canvas->translate(SkIntToScalar(N + 8), 0);
111        canvas->drawBitmapRect(fBitmap, NULL, dst, &paint);
112        canvas->translate(-SkIntToScalar(N + 8), SkIntToScalar(N + 8));
113        canvas->drawBitmapRect(bitmap, NULL, dst, NULL);
114        canvas->translate(SkIntToScalar(N + 8), 0);
115        canvas->drawBitmapRect(bitmap, NULL, dst, &paint);
116
117        SkShader* s = SkShader::CreateBitmapShader(bitmap,
118                                                   SkShader::kRepeat_TileMode,
119                                                   SkShader::kRepeat_TileMode);
120        paint.setShader(s)->unref();
121        SkMatrix m;
122        m.setScale(SkIntToScalar(fWidth) / N,
123                   SkIntToScalar(fWidth) / N);
124        s->setLocalMatrix(m);
125        SkRect r;
126        r.set(0, 0, SkIntToScalar(4*N), SkIntToScalar(5*N/2));
127        r.offset(SkIntToScalar(N + 12), -SkIntToScalar(N + 4));
128        canvas->drawRect(r, paint);
129
130        this->inval(NULL);
131    }
132
133private:
134    int fWidth;
135
136    typedef SampleView INHERITED;
137};
138
139//////////////////////////////////////////////////////////////////////////////
140
141static SkView* MyFactory() { return new MipMapView; }
142static SkViewRegister reg(MyFactory);
143
144