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 8 #include "SkBlurDrawLooper.h" 9 #include "SkBlurMask.h" // just for SkBlurMask::ConvertRadiusToSigma 10 #include "SkBlurMaskFilter.h" 11 #include "SkCanvas.h" 12 #include "SkColorFilter.h" 13 #include "SkReadBuffer.h" 14 #include "SkWriteBuffer.h" 15 #include "SkMaskFilter.h" 16 #include "SkPaint.h" 17 #include "SkString.h" 18 #include "SkStringUtils.h" 19 20 SkBlurDrawLooper::SkBlurDrawLooper(SkColor color, SkScalar sigma, 21 SkScalar dx, SkScalar dy, uint32_t flags) { 22 this->init(sigma, dx, dy, color, flags); 23 } 24 25 // only call from constructor 26 void SkBlurDrawLooper::initEffects() { 27 SkASSERT(fBlurFlags <= kAll_BlurFlag); 28 if (fSigma > 0) { 29 uint32_t flags = fBlurFlags & kIgnoreTransform_BlurFlag ? 30 SkBlurMaskFilter::kIgnoreTransform_BlurFlag : 31 SkBlurMaskFilter::kNone_BlurFlag; 32 33 flags |= fBlurFlags & kHighQuality_BlurFlag ? 34 SkBlurMaskFilter::kHighQuality_BlurFlag : 35 SkBlurMaskFilter::kNone_BlurFlag; 36 37 fBlur = SkBlurMaskFilter::Create(kNormal_SkBlurStyle, fSigma, flags); 38 } else { 39 fBlur = NULL; 40 } 41 42 if (fBlurFlags & kOverrideColor_BlurFlag) { 43 // Set alpha to 1 for the override since transparency will already 44 // be baked into the blurred mask. 45 SkColor opaqueColor = SkColorSetA(fBlurColor, 255); 46 //The SrcIn xfer mode will multiply 'color' by the incoming alpha 47 fColorFilter = SkColorFilter::CreateModeFilter(opaqueColor, 48 SkXfermode::kSrcIn_Mode); 49 } else { 50 fColorFilter = NULL; 51 } 52 } 53 54 void SkBlurDrawLooper::init(SkScalar sigma, SkScalar dx, SkScalar dy, 55 SkColor color, uint32_t flags) { 56 fSigma = sigma; 57 fDx = dx; 58 fDy = dy; 59 fBlurColor = color; 60 fBlurFlags = flags; 61 62 this->initEffects(); 63 } 64 65 SkBlurDrawLooper::SkBlurDrawLooper(SkReadBuffer& buffer) : INHERITED(buffer) { 66 67 fSigma = buffer.readScalar(); 68 fDx = buffer.readScalar(); 69 fDy = buffer.readScalar(); 70 fBlurColor = buffer.readColor(); 71 fBlurFlags = buffer.readUInt() & kAll_BlurFlag; 72 73 this->initEffects(); 74 } 75 76 void SkBlurDrawLooper::flatten(SkWriteBuffer& buffer) const { 77 this->INHERITED::flatten(buffer); 78 buffer.writeScalar(fSigma); 79 buffer.writeScalar(fDx); 80 buffer.writeScalar(fDy); 81 buffer.writeColor(fBlurColor); 82 buffer.write32(fBlurFlags); 83 } 84 85 SkBlurDrawLooper::~SkBlurDrawLooper() { 86 SkSafeUnref(fBlur); 87 SkSafeUnref(fColorFilter); 88 } 89 90 bool SkBlurDrawLooper::asABlurShadow(BlurShadowRec* rec) const { 91 if (fSigma <= 0 || (fBlurFlags & fBlurFlags & kIgnoreTransform_BlurFlag)) { 92 return false; 93 } 94 95 if (rec) { 96 rec->fSigma = fSigma; 97 rec->fColor = fBlurColor; 98 rec->fOffset.set(fDx, fDy); 99 rec->fStyle = kNormal_SkBlurStyle; 100 rec->fQuality = (fBlurFlags & kHighQuality_BlurFlag) ? 101 kHigh_SkBlurQuality : kLow_SkBlurQuality; 102 } 103 return true; 104 } 105 106 //////////////////////////////////////////////////////////////////////////////////////// 107 108 SkDrawLooper::Context* SkBlurDrawLooper::createContext(SkCanvas*, void* storage) const { 109 return SkNEW_PLACEMENT_ARGS(storage, BlurDrawLooperContext, (this)); 110 } 111 112 SkBlurDrawLooper::BlurDrawLooperContext::BlurDrawLooperContext( 113 const SkBlurDrawLooper* looper) 114 : fLooper(looper), fState(SkBlurDrawLooper::kBeforeEdge) {} 115 116 bool SkBlurDrawLooper::BlurDrawLooperContext::next(SkCanvas* canvas, 117 SkPaint* paint) { 118 switch (fState) { 119 case kBeforeEdge: 120 // we do nothing if a maskfilter is already installed 121 if (paint->getMaskFilter()) { 122 fState = kDone; 123 return false; 124 } 125 #ifdef SK_BUILD_FOR_ANDROID 126 SkColor blurColor; 127 blurColor = fLooper->fBlurColor; 128 if (SkColorGetA(blurColor) == 255) { 129 blurColor = SkColorSetA(blurColor, paint->getAlpha()); 130 } 131 paint->setColor(blurColor); 132 #else 133 paint->setColor(fLooper->fBlurColor); 134 #endif 135 paint->setMaskFilter(fLooper->fBlur); 136 paint->setColorFilter(fLooper->fColorFilter); 137 canvas->save(); 138 if (fLooper->fBlurFlags & kIgnoreTransform_BlurFlag) { 139 SkMatrix transform(canvas->getTotalMatrix()); 140 transform.postTranslate(fLooper->fDx, fLooper->fDy); 141 canvas->setMatrix(transform); 142 } else { 143 canvas->translate(fLooper->fDx, fLooper->fDy); 144 } 145 fState = kAfterEdge; 146 return true; 147 case kAfterEdge: 148 canvas->restore(); 149 fState = kDone; 150 return true; 151 default: 152 SkASSERT(kDone == fState); 153 return false; 154 } 155 } 156 157 #ifndef SK_IGNORE_TO_STRING 158 void SkBlurDrawLooper::toString(SkString* str) const { 159 str->append("SkBlurDrawLooper: "); 160 161 str->append("dx: "); 162 str->appendScalar(fDx); 163 164 str->append(" dy: "); 165 str->appendScalar(fDy); 166 167 str->append(" color: "); 168 str->appendHex(fBlurColor); 169 170 str->append(" flags: ("); 171 if (kNone_BlurFlag == fBlurFlags) { 172 str->append("None"); 173 } else { 174 bool needsSeparator = false; 175 SkAddFlagToString(str, SkToBool(kIgnoreTransform_BlurFlag & fBlurFlags), "IgnoreTransform", 176 &needsSeparator); 177 SkAddFlagToString(str, SkToBool(kOverrideColor_BlurFlag & fBlurFlags), "OverrideColor", 178 &needsSeparator); 179 SkAddFlagToString(str, SkToBool(kHighQuality_BlurFlag & fBlurFlags), "HighQuality", 180 &needsSeparator); 181 } 182 str->append(")"); 183 184 // TODO: add optional "fBlurFilter->toString(str);" when SkMaskFilter::toString is added 185 // alternatively we could cache the radius in SkBlurDrawLooper and just add it here 186 } 187 #endif 188
