1/* 2 * Copyright 2011 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#include "SampleCode.h" 8#include "SkView.h" 9#include "SkCanvas.h" 10#include "SkGradientShader.h" 11#include "SkPath.h" 12#include "SkRegion.h" 13#include "SkShader.h" 14#include "SkUtils.h" 15#include "Sk1DPathEffect.h" 16#include "SkCornerPathEffect.h" 17#include "SkPathMeasure.h" 18#include "SkRandom.h" 19#include "SkColorPriv.h" 20#include "SkColorFilter.h" 21#include "SkDither.h" 22 23static void draw_sweep(SkCanvas* c, int width, int height, SkScalar angle) { 24 SkRect r; 25 SkPaint p; 26 27 p.setAntiAlias(true); 28// p.setDither(true); 29 p.setStrokeWidth(SkIntToScalar(width/10)); 30 p.setStyle(SkPaint::kStroke_Style); 31 32 r.set(0, 0, SkIntToScalar(width), SkIntToScalar(height)); 33 34 // SkColor colors[] = { SK_ColorRED, SK_ColorBLUE, SK_ColorGREEN, SK_ColorCYAN }; 35 SkColor colors[] = { 0x4c737373, 0x4c737373, 0xffffd300 }; 36 p.setShader(SkGradientShader::MakeSweep(r.centerX(), r.centerY(), 37 colors, nullptr, SK_ARRAY_COUNT(colors))); 38 39 SkAutoCanvasRestore acr(c, true); 40 c->rotate(angle, r.centerX(), r.centerY()); 41 42 SkRect bounds = r; 43 r.inset(p.getStrokeWidth(), p.getStrokeWidth()); 44 SkRect innerBounds = r; 45 46 if (true) { 47 c->drawOval(r, p); 48 } else { 49 SkScalar x = r.centerX(); 50 SkScalar y = r.centerY(); 51 SkScalar radius = r.width() / 2; 52 SkScalar thickness = p.getStrokeWidth(); 53 SkScalar sweep = 360.0f; 54 SkPath path; 55 56 path.moveTo(x + radius, y); 57 // outer top 58 path.lineTo(x + radius + thickness, y); 59 // outer arc 60 path.arcTo(bounds, 0, sweep, false); 61 // inner arc 62 path.arcTo(innerBounds, sweep, -sweep, false); 63 path.close(); 64 } 65} 66 67static void make_bm(SkBitmap* bm) { 68 bm->allocN32Pixels(100, 100); 69 bm->eraseColor(SK_ColorTRANSPARENT); 70 71 SkCanvas c(*bm); 72 draw_sweep(&c, bm->width(), bm->height(), 0); 73} 74 75static void pre_dither(const SkBitmap& bm) { 76 SkAutoLockPixels alp(bm); 77 78 for (int y = 0; y < bm.height(); y++) { 79 DITHER_4444_SCAN(y); 80 81 SkPMColor* p = bm.getAddr32(0, y); 82 for (int x = 0; x < bm.width(); x++) { 83 SkPMColor c = *p; 84 85 unsigned a = SkGetPackedA32(c); 86 unsigned r = SkGetPackedR32(c); 87 unsigned g = SkGetPackedG32(c); 88 unsigned b = SkGetPackedB32(c); 89 90 unsigned d = DITHER_VALUE(x); 91 92 a = SkDITHER_A32To4444(a, d); 93 r = SkDITHER_R32To4444(r, d); 94 g = SkDITHER_G32To4444(g, d); 95 b = SkDITHER_B32To4444(b, d); 96 97 a = SkA4444ToA32(a); 98 r = SkR4444ToR32(r); 99 g = SkG4444ToG32(g); 100 b = SkB4444ToB32(b); 101 102 *p++ = SkPackARGB32(a, r, g, b); 103 } 104 } 105} 106 107class DitherView : public SampleView { 108public: 109 SkBitmap fBM, fBMPreDither, fBM16; 110 SkScalar fAngle; 111 112 DitherView() { 113 make_bm(&fBM); 114 make_bm(&fBMPreDither); 115 pre_dither(fBMPreDither); 116 fBM.copyTo(&fBM16, kARGB_4444_SkColorType); 117 118 fAngle = 0; 119 120 this->setBGColor(0xFF181818); 121 } 122 123protected: 124 // overrides from SkEventSink 125 virtual bool onQuery(SkEvent* evt) { 126 if (SampleCode::TitleQ(*evt)) { 127 SampleCode::TitleR(evt, "Dither"); 128 return true; 129 } 130 return this->INHERITED::onQuery(evt); 131 } 132 133 virtual void onDrawContent(SkCanvas* canvas) { 134 SkPaint paint; 135 SkScalar x = SkIntToScalar(10); 136 SkScalar y = SkIntToScalar(10); 137 const SkScalar DX = SkIntToScalar(fBM.width() + 10); 138 139 paint.setAntiAlias(true); 140 141 if (true) { 142 canvas->drawBitmap(fBM, x, y, &paint); 143 x += DX; 144 paint.setDither(true); 145 canvas->drawBitmap(fBM, x, y, &paint); 146 147 x += DX; 148 paint.setDither(false); 149 canvas->drawBitmap(fBMPreDither, x, y, &paint); 150 151 x += DX; 152 canvas->drawBitmap(fBM16, x, y, &paint); 153 } 154 155 canvas->translate(DX, DX*2); 156 draw_sweep(canvas, fBM.width(), fBM.height(), fAngle); 157 canvas->translate(DX, 0); 158 draw_sweep(canvas, fBM.width()>>1, fBM.height()>>1, fAngle); 159 canvas->translate(DX, 0); 160 draw_sweep(canvas, fBM.width()>>2, fBM.height()>>2, fAngle); 161 162 fAngle += SK_Scalar1/2; 163 this->inval(nullptr); 164 } 165 166private: 167 typedef SampleView INHERITED; 168}; 169 170////////////////////////////////////////////////////////////////////////////// 171 172static SkView* MyFactory() { return new DitherView; } 173static SkViewRegister reg(MyFactory); 174