aboutsummaryrefslogtreecommitdiffstats
path: root/samplecode/SampleShaders.cpp
blob: 99cd680047780a692c7a513cac1f8d1646f3bf80 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141

/*
 * Copyright 2011 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */
#include "SampleCode.h"
#include "SkView.h"
#include "SkCanvas.h"
#include "SkGradientShader.h"
#include "SkGraphics.h"
#include "SkImageDecoder.h"
#include "SkPath.h"
#include "SkRegion.h"
#include "SkShader.h"
#include "SkUtils.h"
#include "SkXfermode.h"
#include "SkComposeShader.h"
#include "SkColorPriv.h"
#include "SkColorFilter.h"
#include "SkTime.h"
#include "SkTransparentShader.h"
#include "SkTypeface.h"

static SkShader* make_bitmapfade(const SkBitmap& bm)
{
    SkPoint pts[2];
    SkColor colors[2];

    pts[0].set(0, 0);
    pts[1].set(0, SkIntToScalar(bm.height()));
    colors[0] = SK_ColorBLACK;
    colors[1] = SkColorSetARGB(0, 0, 0, 0);
    SkShader* shaderA = SkGradientShader::CreateLinear(pts, colors, NULL, 2, SkShader::kClamp_TileMode);

    SkShader* shaderB = SkShader::CreateBitmapShader(bm,
                        SkShader::kClamp_TileMode, SkShader::kClamp_TileMode);

    SkXfermode* mode = SkXfermode::Create(SkXfermode::kDstIn_Mode);

    SkShader* shader = new SkComposeShader(shaderB, shaderA, mode);
    shaderA->unref();
    shaderB->unref();
    mode->unref();

    return shader;
}

class ShaderView : public SampleView {
public:
    SkShader*   fShader;
    SkBitmap    fBitmap;

	ShaderView() {
        SkImageDecoder::DecodeFile("/skimages/logo.gif", &fBitmap);

        SkPoint pts[2];
        SkColor colors[2];

        pts[0].set(0, 0);
        pts[1].set(SkIntToScalar(100), 0);
        colors[0] = SK_ColorRED;
        colors[1] = SK_ColorBLUE;
        SkShader* shaderA = SkGradientShader::CreateLinear(pts, colors, NULL, 2, SkShader::kClamp_TileMode);

        pts[0].set(0, 0);
        pts[1].set(0, SkIntToScalar(100));
        colors[0] = SK_ColorBLACK;
        colors[1] = SkColorSetARGB(0x80, 0, 0, 0);
        SkShader* shaderB = SkGradientShader::CreateLinear(pts, colors, NULL, 2, SkShader::kClamp_TileMode);

        SkXfermode* mode = SkXfermode::Create(SkXfermode::kDstIn_Mode);

        fShader = new SkComposeShader(shaderA, shaderB, mode);
        shaderA->unref();
        shaderB->unref();
        mode->unref();
    }
    virtual ~ShaderView() {
        SkSafeUnref(fShader);
    }

protected:
    // overrides from SkEventSink
    virtual bool onQuery(SkEvent* evt) {
        if (SampleCode::TitleQ(*evt)) {
            SampleCode::TitleR(evt, "Shaders");
            return true;
        }
        return this->INHERITED::onQuery(evt);
    }

    virtual void onDrawContent(SkCanvas* canvas) {
        canvas->drawBitmap(fBitmap, 0, 0);

        canvas->translate(SkIntToScalar(20), SkIntToScalar(120));

        SkPaint paint;
        SkRect  r;

        paint.setColor(SK_ColorGREEN);
        canvas->drawRectCoords(0, 0, SkIntToScalar(100), SkIntToScalar(100), paint);
        paint.setShader(fShader);
        canvas->drawRectCoords(0, 0, SkIntToScalar(100), SkIntToScalar(100), paint);

        canvas->translate(SkIntToScalar(110), 0);

        int w = fBitmap.width();
        int h = fBitmap.height();
        w = 120;
        h = 80;
        r.set(0, 0, SkIntToScalar(w), SkIntToScalar(h));

        paint.setShader(NULL);
        canvas->drawRect(r, paint);
        paint.setShader(make_bitmapfade(fBitmap))->unref();
        canvas->drawRect(r, paint);

        paint.setShader(new SkTransparentShader)->unref();
        canvas->drawRect(r, paint);
    }

    virtual SkView::Click* onFindClickHandler(SkScalar x, SkScalar y) {
        this->inval(NULL);
        return this->INHERITED::onFindClickHandler(x, y);
    }

    virtual bool onClick(Click* click) {
        return this->INHERITED::onClick(click);
    }

private:
    typedef SampleView INHERITED;
};

//////////////////////////////////////////////////////////////////////////////

static SkView* MyFactory() { return new ShaderView; }
static SkViewRegister reg(MyFactory);