1 /* 2 * Copyright 2013 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 "gm.h" 8 #include "sk_tool_utils.h" 9 #include "SkBitmap.h" 10 #include "SkPath.h" 11 #include "SkRandom.h" 12 #include "SkShader.h" 13 #include "SkSurface.h" 14 15 namespace skiagm { 16 17 /** 18 * Renders overlapping shapes with colorburn against a checkerboard. 19 */ 20 class DstReadShuffle : public GM { 21 public: DstReadShuffle()22 DstReadShuffle() { this->setBGColor(kBackground); } 23 24 protected: 25 enum ShapeType { 26 kCircle_ShapeType, 27 kRoundRect_ShapeType, 28 kRect_ShapeType, 29 kConvexPath_ShapeType, 30 kConcavePath_ShapeType, 31 kText_ShapeType, 32 kNumShapeTypes 33 }; 34 onShortName()35 SkString onShortName() override { 36 return SkString("dstreadshuffle"); 37 } 38 onISize()39 SkISize onISize() override { 40 return SkISize::Make(530, 680); 41 } 42 drawShape(SkCanvas * canvas,SkPaint * paint,ShapeType type)43 void drawShape(SkCanvas* canvas, SkPaint* paint, ShapeType type) { 44 const SkRect kRect = SkRect::MakeXYWH(0, 0, 75.f, 85.f); 45 switch (type) { 46 case kCircle_ShapeType: 47 canvas->drawCircle(kRect.centerX(), kRect.centerY(), kRect.width() / 2.f, *paint); 48 break; 49 case kRoundRect_ShapeType: 50 canvas->drawRoundRect(kRect, 15.f, 15.f, *paint); 51 break; 52 case kRect_ShapeType: 53 canvas->drawRect(kRect, *paint); 54 break; 55 case kConvexPath_ShapeType: 56 if (fConvexPath.isEmpty()) { 57 SkPoint points[4]; 58 kRect.toQuad(points); 59 fConvexPath.moveTo(points[0]); 60 fConvexPath.quadTo(points[1], points[2]); 61 fConvexPath.quadTo(points[3], points[0]); 62 SkASSERT(fConvexPath.isConvex()); 63 } 64 canvas->drawPath(fConvexPath, *paint); 65 break; 66 case kConcavePath_ShapeType: 67 if (fConcavePath.isEmpty()) { 68 SkPoint points[5] = {{50.f, 0.f}}; 69 SkMatrix rot; 70 rot.setRotate(360.f / 5, 50.f, 70.f); 71 for (int i = 1; i < 5; ++i) { 72 rot.mapPoints(points + i, points + i - 1, 1); 73 } 74 fConcavePath.moveTo(points[0]); 75 for (int i = 0; i < 5; ++i) { 76 fConcavePath.lineTo(points[(2 * i) % 5]); 77 } 78 fConcavePath.setFillType(SkPath::kEvenOdd_FillType); 79 SkASSERT(!fConcavePath.isConvex()); 80 } 81 canvas->drawPath(fConcavePath, *paint); 82 break; 83 case kText_ShapeType: { 84 const char* text = "N"; 85 SkFont font(sk_tool_utils::create_portable_typeface(), 100); 86 font.setEmbolden(true); 87 canvas->drawString(text, 0.f, 100.f, font, *paint); 88 } 89 default: 90 break; 91 } 92 } 93 GetColor(SkRandom * random)94 static SkColor GetColor(SkRandom* random) { 95 SkColor color = sk_tool_utils::color_to_565(random->nextU() | 0xFF000000); 96 return SkColorSetA(color, 0x80); 97 } 98 DrawHairlines(SkCanvas * canvas)99 static void DrawHairlines(SkCanvas* canvas) { 100 if (canvas->imageInfo().alphaType() == kOpaque_SkAlphaType) { 101 canvas->clear(kBackground); 102 } else { 103 canvas->clear(SK_ColorTRANSPARENT); 104 } 105 SkPaint hairPaint; 106 hairPaint.setStyle(SkPaint::kStroke_Style); 107 hairPaint.setStrokeWidth(0); 108 hairPaint.setAntiAlias(true); 109 static constexpr int kNumHairlines = 12; 110 SkPoint pts[] = {{3.f, 7.f}, {29.f, 7.f}}; 111 SkRandom colorRandom; 112 SkMatrix rot; 113 rot.setRotate(360.f / kNumHairlines, 15.5f, 12.f); 114 rot.postTranslate(3.f, 0); 115 for (int i = 0; i < 12; ++i) { 116 hairPaint.setColor(GetColor(&colorRandom)); 117 canvas->drawLine(pts[0], pts[1], hairPaint); 118 rot.mapPoints(pts, 2); 119 } 120 } 121 onDraw(SkCanvas * canvas)122 void onDraw(SkCanvas* canvas) override { 123 SkScalar y = 5; 124 for (int i = 0; i < kNumShapeTypes; i++) { 125 SkRandom colorRandom; 126 ShapeType shapeType = static_cast<ShapeType>(i); 127 SkScalar x = 5; 128 for (int r = 0; r <= 15; r++) { 129 SkPaint p; 130 p.setAntiAlias(true); 131 p.setColor(GetColor(&colorRandom)); 132 // In order to get some op combining on the GPU backend we do 2 src over 133 // for each xfer mode which requires a dst read 134 p.setBlendMode(r % 3 == 0 ? SkBlendMode::kColorBurn : SkBlendMode::kSrcOver); 135 canvas->save(); 136 canvas->translate(x, y); 137 this->drawShape(canvas, &p, shapeType); 138 canvas->restore(); 139 x += 15; 140 } 141 y += 110; 142 } 143 // Draw hairlines to a surface and then draw that to the main canvas with a zoom so that 144 // it is easier to see how they blend. 145 SkImageInfo info; 146 // Recording canvases don't have a color type. 147 if (SkColorType::kUnknown_SkColorType == canvas->imageInfo().colorType()) { 148 info = SkImageInfo::MakeN32Premul(35, 35); 149 } else { 150 info = SkImageInfo::Make(35, 35, 151 canvas->imageInfo().colorType(), 152 canvas->imageInfo().alphaType(), 153 canvas->imageInfo().refColorSpace()); 154 } 155 auto surf = canvas->makeSurface(info); 156 if (!surf) { 157 // Fall back to raster. Raster supports only one of the 8 bit per-channel RGBA or BGRA 158 // formats. This fall back happens when running with --preAbandonGpuContext. 159 if ((info.colorType() == kRGBA_8888_SkColorType || 160 info.colorType() == kBGRA_8888_SkColorType) && 161 info.colorType() != kN32_SkColorType) { 162 info = SkImageInfo::Make(35, 35, 163 kN32_SkColorType, 164 canvas->imageInfo().alphaType(), 165 canvas->imageInfo().refColorSpace()); 166 } 167 surf = SkSurface::MakeRaster(info); 168 SkASSERT(surf); 169 } 170 canvas->scale(5.f, 5.f); 171 canvas->translate(67.f, 10.f); 172 DrawHairlines(surf->getCanvas()); 173 canvas->drawImage(surf->makeImageSnapshot(), 0.f, 0.f); 174 } 175 176 private: 177 static constexpr SkColor kBackground = SK_ColorLTGRAY; 178 SkPath fConcavePath; 179 SkPath fConvexPath; 180 typedef GM INHERITED; 181 }; 182 183 ////////////////////////////////////////////////////////////////////////////// 184 185 DEF_GM( return new DstReadShuffle; ) 186 187 } 188