michael@0: 
michael@0: /*
michael@0:  * Copyright 2011 Google Inc.
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: #include "SkBlurDrawLooper.h"
michael@0: #include "SkBlurMask.h"     // just for SkBlurMask::ConvertRadiusToSigma
michael@0: #include "SkBlurMaskFilter.h"
michael@0: #include "SkCanvas.h"
michael@0: #include "SkColorFilter.h"
michael@0: #include "SkReadBuffer.h"
michael@0: #include "SkWriteBuffer.h"
michael@0: #include "SkMaskFilter.h"
michael@0: #include "SkPaint.h"
michael@0: #include "SkString.h"
michael@0: #include "SkStringUtils.h"
michael@0: 
michael@0: SkBlurDrawLooper::SkBlurDrawLooper(SkScalar radius, SkScalar dx, SkScalar dy,
michael@0:                                    SkColor color, uint32_t flags) {
michael@0:     this->init(SkBlurMask::ConvertRadiusToSigma(radius), dx, dy, color, flags);
michael@0: }
michael@0: 
michael@0: SkBlurDrawLooper::SkBlurDrawLooper(SkColor color, SkScalar sigma,
michael@0:                                    SkScalar dx, SkScalar dy, uint32_t flags) {
michael@0:     this->init(sigma, dx, dy, color, flags);
michael@0: }
michael@0: 
michael@0: void SkBlurDrawLooper::init(SkScalar sigma, SkScalar dx, SkScalar dy,
michael@0:                             SkColor color, uint32_t flags) {
michael@0:     fDx = dx;
michael@0:     fDy = dy;
michael@0:     fBlurColor = color;
michael@0:     fBlurFlags = flags;
michael@0: 
michael@0:     SkASSERT(flags <= kAll_BlurFlag);
michael@0:     if (sigma > 0) {
michael@0:         uint32_t blurFlags = flags & kIgnoreTransform_BlurFlag ?
michael@0:             SkBlurMaskFilter::kIgnoreTransform_BlurFlag :
michael@0:             SkBlurMaskFilter::kNone_BlurFlag;
michael@0: 
michael@0:         blurFlags |= flags & kHighQuality_BlurFlag ?
michael@0:             SkBlurMaskFilter::kHighQuality_BlurFlag :
michael@0:             SkBlurMaskFilter::kNone_BlurFlag;
michael@0: 
michael@0:         fBlur = SkBlurMaskFilter::Create(SkBlurMaskFilter::kNormal_BlurStyle,
michael@0:                                          sigma,
michael@0:                                          blurFlags);
michael@0:     } else {
michael@0:         fBlur = NULL;
michael@0:     }
michael@0: 
michael@0:     if (flags & kOverrideColor_BlurFlag) {
michael@0:         // Set alpha to 1 for the override since transparency will already
michael@0:         // be baked into the blurred mask.
michael@0:         SkColor opaqueColor = SkColorSetA(color, 255);
michael@0:         //The SrcIn xfer mode will multiply 'color' by the incoming alpha
michael@0:         fColorFilter = SkColorFilter::CreateModeFilter(opaqueColor,
michael@0:                                                        SkXfermode::kSrcIn_Mode);
michael@0:     } else {
michael@0:         fColorFilter = NULL;
michael@0:     }
michael@0: }
michael@0: 
michael@0: SkBlurDrawLooper::SkBlurDrawLooper(SkReadBuffer& buffer)
michael@0: : INHERITED(buffer) {
michael@0: 
michael@0:     fDx = buffer.readScalar();
michael@0:     fDy = buffer.readScalar();
michael@0:     fBlurColor = buffer.readColor();
michael@0:     fBlur = buffer.readMaskFilter();
michael@0:     fColorFilter = buffer.readColorFilter();
michael@0:     fBlurFlags = buffer.readUInt() & kAll_BlurFlag;
michael@0: }
michael@0: 
michael@0: SkBlurDrawLooper::~SkBlurDrawLooper() {
michael@0:     SkSafeUnref(fBlur);
michael@0:     SkSafeUnref(fColorFilter);
michael@0: }
michael@0: 
michael@0: void SkBlurDrawLooper::flatten(SkWriteBuffer& buffer) const {
michael@0:     this->INHERITED::flatten(buffer);
michael@0:     buffer.writeScalar(fDx);
michael@0:     buffer.writeScalar(fDy);
michael@0:     buffer.writeColor(fBlurColor);
michael@0:     buffer.writeFlattenable(fBlur);
michael@0:     buffer.writeFlattenable(fColorFilter);
michael@0:     buffer.writeUInt(fBlurFlags);
michael@0: }
michael@0: 
michael@0: SkDrawLooper::Context* SkBlurDrawLooper::createContext(SkCanvas*, void* storage) const {
michael@0:     return SkNEW_PLACEMENT_ARGS(storage, BlurDrawLooperContext, (this));
michael@0: }
michael@0: 
michael@0: SkBlurDrawLooper::BlurDrawLooperContext::BlurDrawLooperContext(
michael@0:         const SkBlurDrawLooper* looper)
michael@0:     : fLooper(looper), fState(SkBlurDrawLooper::kBeforeEdge) {}
michael@0: 
michael@0: bool SkBlurDrawLooper::BlurDrawLooperContext::next(SkCanvas* canvas,
michael@0:                                                    SkPaint* paint) {
michael@0:     switch (fState) {
michael@0:         case kBeforeEdge:
michael@0:             // we do nothing if a maskfilter is already installed
michael@0:             if (paint->getMaskFilter()) {
michael@0:                 fState = kDone;
michael@0:                 return false;
michael@0:             }
michael@0: #ifdef SK_BUILD_FOR_ANDROID
michael@0:             SkColor blurColor;
michael@0:             blurColor = fLooper->fBlurColor;
michael@0:             if (SkColorGetA(blurColor) == 255) {
michael@0:                 blurColor = SkColorSetA(blurColor, paint->getAlpha());
michael@0:             }
michael@0:             paint->setColor(blurColor);
michael@0: #else
michael@0:             paint->setColor(fLooper->fBlurColor);
michael@0: #endif
michael@0:             paint->setMaskFilter(fLooper->fBlur);
michael@0:             paint->setColorFilter(fLooper->fColorFilter);
michael@0:             canvas->save(SkCanvas::kMatrix_SaveFlag);
michael@0:             if (fLooper->fBlurFlags & kIgnoreTransform_BlurFlag) {
michael@0:                 SkMatrix transform(canvas->getTotalMatrix());
michael@0:                 transform.postTranslate(fLooper->fDx, fLooper->fDy);
michael@0:                 canvas->setMatrix(transform);
michael@0:             } else {
michael@0:                 canvas->translate(fLooper->fDx, fLooper->fDy);
michael@0:             }
michael@0:             fState = kAfterEdge;
michael@0:             return true;
michael@0:         case kAfterEdge:
michael@0:             canvas->restore();
michael@0:             fState = kDone;
michael@0:             return true;
michael@0:         default:
michael@0:             SkASSERT(kDone == fState);
michael@0:             return false;
michael@0:     }
michael@0: }
michael@0: 
michael@0: #ifndef SK_IGNORE_TO_STRING
michael@0: void SkBlurDrawLooper::toString(SkString* str) const {
michael@0:     str->append("SkBlurDrawLooper: ");
michael@0: 
michael@0:     str->append("dx: ");
michael@0:     str->appendScalar(fDx);
michael@0: 
michael@0:     str->append(" dy: ");
michael@0:     str->appendScalar(fDy);
michael@0: 
michael@0:     str->append(" color: ");
michael@0:     str->appendHex(fBlurColor);
michael@0: 
michael@0:     str->append(" flags: (");
michael@0:     if (kNone_BlurFlag == fBlurFlags) {
michael@0:         str->append("None");
michael@0:     } else {
michael@0:         bool needsSeparator = false;
michael@0:         SkAddFlagToString(str, SkToBool(kIgnoreTransform_BlurFlag & fBlurFlags), "IgnoreTransform",
michael@0:                           &needsSeparator);
michael@0:         SkAddFlagToString(str, SkToBool(kOverrideColor_BlurFlag & fBlurFlags), "OverrideColor",
michael@0:                           &needsSeparator);
michael@0:         SkAddFlagToString(str, SkToBool(kHighQuality_BlurFlag & fBlurFlags), "HighQuality",
michael@0:                           &needsSeparator);
michael@0:     }
michael@0:     str->append(")");
michael@0: 
michael@0:     // TODO: add optional "fBlurFilter->toString(str);" when SkMaskFilter::toString is added
michael@0:     // alternatively we could cache the radius in SkBlurDrawLooper and just add it here
michael@0: }
michael@0: #endif