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