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      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 
     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 
     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 
     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 
     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, kOpaque_SkAlphaType);
     61 
     62     SkBitmap bm;
     63     bm.allocPixels(SkImageInfo::Make(256, 32, kIndex_8_SkColorType,
     64                                      kPremul_SkAlphaType),
     65                    NULL, ctable);
     66     ctable->unref();
     67 
     68     bm.lockPixels();
     69     for (int y = 0; y < bm.height(); y++) {
     70         uint8_t* p = bm.getAddr8(0, y);
     71         for (int x = 0; x < 256; x++) {
     72             p[x] = x;
     73         }
     74     }
     75     bm.unlockPixels();
     76     return bm;
     77 }
     78 
     79 class DitherBitmapView : public SampleView {
     80     SkBitmap    fBM8;
     81     SkBitmap    fBM32;
     82     bool        fResult;
     83 public:
     84     DitherBitmapView() {
     85         fResult = test_pathregion();
     86         fBM8 = make_bitmap();
     87         fBM8.copyTo(&fBM32, kN32_SkColorType);
     88 
     89         this->setBGColor(0xFFDDDDDD);
     90     }
     91 
     92 protected:
     93     // overrides from SkEventSink
     94     virtual bool onQuery(SkEvent* evt) {
     95         if (SampleCode::TitleQ(*evt)) {
     96             SampleCode::TitleR(evt, "DitherBitmap");
     97             return true;
     98         }
     99         return this->INHERITED::onQuery(evt);
    100     }
    101 
    102     static void setBitmapOpaque(SkBitmap* bm, bool isOpaque) {
    103         SkAutoLockPixels alp(*bm);  // needed for ctable
    104         bm->setAlphaType(isOpaque ? kOpaque_SkAlphaType : kPremul_SkAlphaType);
    105     }
    106 
    107     static void draw2(SkCanvas* canvas, const SkBitmap& bm) {
    108         SkPaint paint;
    109         SkBitmap bitmap(bm);
    110 
    111         setBitmapOpaque(&bitmap, false);
    112         paint.setDither(false);
    113         canvas->drawBitmap(bitmap, 0, 0, &paint);
    114         paint.setDither(true);
    115         canvas->drawBitmap(bitmap, 0, SkIntToScalar(bm.height() + 10), &paint);
    116 
    117         setBitmapOpaque(&bitmap, true);
    118         SkScalar x = SkIntToScalar(bm.width() + 10);
    119         paint.setDither(false);
    120         canvas->drawBitmap(bitmap, x, 0, &paint);
    121         paint.setDither(true);
    122         canvas->drawBitmap(bitmap, x, SkIntToScalar(bm.height() + 10), &paint);
    123     }
    124 
    125     virtual void onDrawContent(SkCanvas* canvas) {
    126         canvas->translate(SkIntToScalar(20), SkIntToScalar(20));
    127 
    128         draw2(canvas, fBM8);
    129         canvas->translate(0, SkIntToScalar(fBM8.height() *3));
    130         draw2(canvas, fBM32);
    131 
    132         canvas->translate(0, SkIntToScalar(fBM8.height() *3));
    133         draw_gradient(canvas);
    134 
    135         char resultTrue[] = "SkRegion::setPath returned true";
    136         char resultFalse[] = "SkRegion::setPath returned false";
    137         SkPaint p;
    138         if (fResult)
    139             canvas->drawText(resultTrue, sizeof(resultTrue) - 1, 0, 50, p);
    140         else
    141             canvas->drawText(resultFalse, sizeof(resultFalse) - 1, 0, 50, p);
    142     }
    143 
    144 private:
    145     typedef SampleView INHERITED;
    146 };
    147 
    148 //////////////////////////////////////////////////////////////////////////////
    149 
    150 static SkView* MyFactory() { return new DitherBitmapView; }
    151 static SkViewRegister reg(MyFactory);
    152