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 8 #include "gm.h" 9 #include "SkBlurMask.h" 10 #include "SkBlurMaskFilter.h" 11 #include "SkCanvas.h" 12 13 // This GM tests out the quick reject bounds of the blur mask filter. It draws 14 // four blurred rects around a central clip. The blurred rect geometry outset 15 // by the blur radius does not overlap the clip rect so, if the blur clipping 16 // just uses the radius, they will be clipped out (and the result will differ 17 // from the result if quick reject were disabled. If the blur clipping uses 18 // the correct 3 sigma bound then the images with and without quick rejecting 19 // will be the same. 20 class BlurQuickRejectGM : public skiagm::GM { 21 public: BlurQuickRejectGM()22 BlurQuickRejectGM() {} 23 24 protected: onShortName()25 SkString onShortName() override { 26 return SkString("blurquickreject"); 27 } 28 onISize()29 SkISize onISize() override { 30 return SkISize::Make(kWidth, kHeight); 31 } 32 onDraw(SkCanvas * canvas)33 void onDraw(SkCanvas* canvas) override { 34 constexpr SkScalar kBlurRadius = SkIntToScalar(20); 35 constexpr SkScalar kBoxSize = SkIntToScalar(100); 36 37 SkRect clipRect = SkRect::MakeXYWH(0, 0, kBoxSize, kBoxSize); 38 SkRect blurRects[] = { 39 { -kBoxSize - (kBlurRadius+1), 0, -(kBlurRadius+1), kBoxSize }, 40 { 0, -kBoxSize - (kBlurRadius+1), kBoxSize, -(kBlurRadius+1) }, 41 { kBoxSize+kBlurRadius+1, 0, 2*kBoxSize+kBlurRadius+1, kBoxSize }, 42 { 0, kBoxSize+kBlurRadius+1, kBoxSize, 2*kBoxSize+kBlurRadius+1 } 43 }; 44 SkColor colors[] = { 45 SK_ColorRED, 46 SK_ColorGREEN, 47 SK_ColorBLUE, 48 SK_ColorYELLOW, 49 }; 50 SkASSERT(SK_ARRAY_COUNT(colors) == SK_ARRAY_COUNT(blurRects)); 51 52 SkPaint hairlinePaint; 53 hairlinePaint.setStyle(SkPaint::kStroke_Style); 54 hairlinePaint.setColor(SK_ColorWHITE); 55 hairlinePaint.setStrokeWidth(0); 56 57 SkPaint blurPaint; 58 blurPaint.setFilterQuality(kLow_SkFilterQuality); 59 blurPaint.setMaskFilter(SkBlurMaskFilter::Make(kNormal_SkBlurStyle, 60 SkBlurMask::ConvertRadiusToSigma(kBlurRadius))); 61 62 canvas->clear(SK_ColorBLACK); 63 canvas->save(); 64 canvas->translate(kBoxSize, kBoxSize); 65 canvas->drawRect(clipRect, hairlinePaint); 66 canvas->clipRect(clipRect); 67 for (size_t i = 0; i < SK_ARRAY_COUNT(blurRects); ++i) { 68 blurPaint.setColor(colors[i]); 69 canvas->drawRect(blurRects[i], blurPaint); 70 canvas->drawRect(blurRects[i], hairlinePaint); 71 } 72 canvas->restore(); 73 } 74 75 private: 76 static constexpr int kWidth = 300; 77 static constexpr int kHeight = 300; 78 79 typedef GM INHERITED; 80 }; 81 82 DEF_GM( return new BlurQuickRejectGM(); ) 83