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 "SkColorPriv.h"
10 #include "SkGradientShader.h"
11 #include "SkView.h"
12 #include "SkCanvas.h"
13 #include "SkUtils.h"
14 
draw_rect(SkCanvas * canvas,const SkRect & r,const SkPaint & p)15 static void draw_rect(SkCanvas* canvas, const SkRect& r, const SkPaint& p) {
16     canvas->drawRect(r, p);
17 
18     SkPaint frame(p);
19     frame.setShader(NULL);
20     frame.setStyle(SkPaint::kStroke_Style);
21     canvas->drawRect(r, frame);
22 }
23 
draw_gradient(SkCanvas * canvas)24 static void draw_gradient(SkCanvas* canvas) {
25     SkRect r = { 0, 0, SkIntToScalar(256), SkIntToScalar(32) };
26     SkPoint pts[] = { { r.fLeft, r.fTop }, { r.fRight, r.fTop } };
27     SkColor colors[] = { 0xFF000000, 0xFFFF0000 };
28     SkShader* s = SkGradientShader::CreateLinear(pts, colors, NULL, 2,
29                                                  SkShader::kClamp_TileMode);
30 
31     SkPaint p;
32     p.setShader(s)->unref();
33     draw_rect(canvas, r, p);
34 
35     canvas->translate(0, SkIntToScalar(40));
36     p.setDither(true);
37     draw_rect(canvas, r, p);
38 }
39 
test_pathregion()40 static bool test_pathregion() {
41     SkPath path;
42     SkRegion region;
43     path.moveTo(25071800.f, -141823808.f);
44     path.lineTo(25075500.f, -141824000.f);
45     path.lineTo(25075400.f, -141827712.f);
46     path.lineTo(25071810.f, -141827600.f);
47     path.close();
48 
49     SkIRect bounds;
50     path.getBounds().round(&bounds);
51     SkRegion clip(bounds);
52     return region.setPath(path, clip); // <-- !! DOWN !!
53 }
54 
make_bitmap()55 static SkBitmap make_bitmap() {
56     SkPMColor c[256];
57     for (int i = 0; i < 256; i++) {
58         c[i] = SkPackARGB32(0xFF, i, 0, 0);
59     }
60     SkColorTable* ctable = new SkColorTable(c, 256);
61 
62     SkBitmap bm;
63     bm.allocPixels(SkImageInfo::Make(256, 32, kIndex_8_SkColorType, kPremul_SkAlphaType),
64                    NULL, ctable);
65     ctable->unref();
66 
67     bm.lockPixels();
68     for (int y = 0; y < bm.height(); y++) {
69         uint8_t* p = bm.getAddr8(0, y);
70         for (int x = 0; x < 256; x++) {
71             p[x] = x;
72         }
73     }
74     bm.unlockPixels();
75     return bm;
76 }
77 
78 class DitherBitmapView : public SampleView {
79     SkBitmap    fBM8;
80     SkBitmap    fBM32;
81     bool        fResult;
82 public:
DitherBitmapView()83     DitherBitmapView() {
84         fResult = test_pathregion();
85         fBM8 = make_bitmap();
86         fBM8.copyTo(&fBM32, kN32_SkColorType);
87 
88         this->setBGColor(0xFFDDDDDD);
89     }
90 
91 protected:
92     // overrides from SkEventSink
onQuery(SkEvent * evt)93     virtual bool onQuery(SkEvent* evt) {
94         if (SampleCode::TitleQ(*evt)) {
95             SampleCode::TitleR(evt, "DitherBitmap");
96             return true;
97         }
98         return this->INHERITED::onQuery(evt);
99     }
100 
setBitmapOpaque(SkBitmap * bm,bool isOpaque)101     static void setBitmapOpaque(SkBitmap* bm, bool isOpaque) {
102         SkAutoLockPixels alp(*bm);  // needed for ctable
103         bm->setAlphaType(isOpaque ? kOpaque_SkAlphaType : kPremul_SkAlphaType);
104     }
105 
draw2(SkCanvas * canvas,const SkBitmap & bm)106     static void draw2(SkCanvas* canvas, const SkBitmap& bm) {
107         SkPaint paint;
108         SkBitmap bitmap(bm);
109 
110         setBitmapOpaque(&bitmap, false);
111         paint.setDither(false);
112         canvas->drawBitmap(bitmap, 0, 0, &paint);
113         paint.setDither(true);
114         canvas->drawBitmap(bitmap, 0, SkIntToScalar(bm.height() + 10), &paint);
115 
116         setBitmapOpaque(&bitmap, true);
117         SkScalar x = SkIntToScalar(bm.width() + 10);
118         paint.setDither(false);
119         canvas->drawBitmap(bitmap, x, 0, &paint);
120         paint.setDither(true);
121         canvas->drawBitmap(bitmap, x, SkIntToScalar(bm.height() + 10), &paint);
122     }
123 
onDrawContent(SkCanvas * canvas)124     virtual void onDrawContent(SkCanvas* canvas) {
125         canvas->translate(SkIntToScalar(20), SkIntToScalar(20));
126 
127         draw2(canvas, fBM8);
128         canvas->translate(0, SkIntToScalar(fBM8.height() *3));
129         draw2(canvas, fBM32);
130 
131         canvas->translate(0, SkIntToScalar(fBM8.height() *3));
132         draw_gradient(canvas);
133 
134         char resultTrue[] = "SkRegion::setPath returned true";
135         char resultFalse[] = "SkRegion::setPath returned false";
136         SkPaint p;
137         if (fResult)
138             canvas->drawText(resultTrue, sizeof(resultTrue) - 1, 0, 50, p);
139         else
140             canvas->drawText(resultFalse, sizeof(resultFalse) - 1, 0, 50, p);
141     }
142 
143 private:
144     typedef SampleView INHERITED;
145 };
146 
147 //////////////////////////////////////////////////////////////////////////////
148 
MyFactory()149 static SkView* MyFactory() { return new DitherBitmapView; }
150 static SkViewRegister reg(MyFactory);
151