michael@0: /*
michael@0:  * Copyright 2010 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: 
michael@0: #include "SkRasterClip.h"
michael@0: 
michael@0: 
michael@0: SkRasterClip::SkRasterClip() {
michael@0:     fIsBW = true;
michael@0:     fIsEmpty = true;
michael@0:     fIsRect = false;
michael@0:     SkDEBUGCODE(this->validate();)
michael@0: }
michael@0: 
michael@0: SkRasterClip::SkRasterClip(const SkRasterClip& src) {
michael@0:     AUTO_RASTERCLIP_VALIDATE(src);
michael@0: 
michael@0:     fIsBW = src.fIsBW;
michael@0:     if (fIsBW) {
michael@0:         fBW = src.fBW;
michael@0:     } else {
michael@0:         fAA = src.fAA;
michael@0:     }
michael@0: 
michael@0:     fIsEmpty = src.isEmpty();
michael@0:     fIsRect = src.isRect();
michael@0:     SkDEBUGCODE(this->validate();)
michael@0: }
michael@0: 
michael@0: SkRasterClip::SkRasterClip(const SkIRect& bounds) : fBW(bounds) {
michael@0:     fIsBW = true;
michael@0:     fIsEmpty = this->computeIsEmpty();  // bounds might be empty, so compute
michael@0:     fIsRect = !fIsEmpty;
michael@0:     SkDEBUGCODE(this->validate();)
michael@0: }
michael@0: 
michael@0: SkRasterClip::~SkRasterClip() {
michael@0:     SkDEBUGCODE(this->validate();)
michael@0: }
michael@0: 
michael@0: bool SkRasterClip::isComplex() const {
michael@0:     return fIsBW ? fBW.isComplex() : !fAA.isEmpty();
michael@0: }
michael@0: 
michael@0: const SkIRect& SkRasterClip::getBounds() const {
michael@0:     return fIsBW ? fBW.getBounds() : fAA.getBounds();
michael@0: }
michael@0: 
michael@0: bool SkRasterClip::setEmpty() {
michael@0:     AUTO_RASTERCLIP_VALIDATE(*this);
michael@0: 
michael@0:     fIsBW = true;
michael@0:     fBW.setEmpty();
michael@0:     fAA.setEmpty();
michael@0:     fIsEmpty = true;
michael@0:     fIsRect = false;
michael@0:     return false;
michael@0: }
michael@0: 
michael@0: bool SkRasterClip::setRect(const SkIRect& rect) {
michael@0:     AUTO_RASTERCLIP_VALIDATE(*this);
michael@0: 
michael@0:     fIsBW = true;
michael@0:     fAA.setEmpty();
michael@0:     fIsRect = fBW.setRect(rect);
michael@0:     fIsEmpty = !fIsRect;
michael@0:     return fIsRect;
michael@0: }
michael@0: 
michael@0: bool SkRasterClip::setPath(const SkPath& path, const SkRegion& clip, bool doAA) {
michael@0:     AUTO_RASTERCLIP_VALIDATE(*this);
michael@0: 
michael@0:     if (this->isBW() && !doAA) {
michael@0:         (void)fBW.setPath(path, clip);
michael@0:     } else {
michael@0:         // TODO: since we are going to over-write fAA completely (aren't we?)
michael@0:         // we should just clear our BW data (if any) and set fIsAA=true
michael@0:         if (this->isBW()) {
michael@0:             this->convertToAA();
michael@0:         }
michael@0:         (void)fAA.setPath(path, &clip, doAA);
michael@0:     }
michael@0:     return this->updateCacheAndReturnNonEmpty();
michael@0: }
michael@0: 
michael@0: bool SkRasterClip::setPath(const SkPath& path, const SkIRect& clip, bool doAA) {
michael@0:     SkRegion tmp;
michael@0:     tmp.setRect(clip);
michael@0:     return this->setPath(path, tmp, doAA);
michael@0: }
michael@0: 
michael@0: bool SkRasterClip::op(const SkIRect& rect, SkRegion::Op op) {
michael@0:     AUTO_RASTERCLIP_VALIDATE(*this);
michael@0: 
michael@0:     fIsBW ? fBW.op(rect, op) : fAA.op(rect, op);
michael@0:     return this->updateCacheAndReturnNonEmpty();
michael@0: }
michael@0: 
michael@0: bool SkRasterClip::op(const SkRegion& rgn, SkRegion::Op op) {
michael@0:     AUTO_RASTERCLIP_VALIDATE(*this);
michael@0: 
michael@0:     if (fIsBW) {
michael@0:         (void)fBW.op(rgn, op);
michael@0:     } else {
michael@0:         SkAAClip tmp;
michael@0:         tmp.setRegion(rgn);
michael@0:         (void)fAA.op(tmp, op);
michael@0:     }
michael@0:     return this->updateCacheAndReturnNonEmpty();
michael@0: }
michael@0: 
michael@0: bool SkRasterClip::op(const SkRasterClip& clip, SkRegion::Op op) {
michael@0:     AUTO_RASTERCLIP_VALIDATE(*this);
michael@0:     clip.validate();
michael@0: 
michael@0:     if (this->isBW() && clip.isBW()) {
michael@0:         (void)fBW.op(clip.fBW, op);
michael@0:     } else {
michael@0:         SkAAClip tmp;
michael@0:         const SkAAClip* other;
michael@0: 
michael@0:         if (this->isBW()) {
michael@0:             this->convertToAA();
michael@0:         }
michael@0:         if (clip.isBW()) {
michael@0:             tmp.setRegion(clip.bwRgn());
michael@0:             other = &tmp;
michael@0:         } else {
michael@0:             other = &clip.aaRgn();
michael@0:         }
michael@0:         (void)fAA.op(*other, op);
michael@0:     }
michael@0:     return this->updateCacheAndReturnNonEmpty();
michael@0: }
michael@0: 
michael@0: /**
michael@0:  *  Our antialiasing currently has a granularity of 1/4 of a pixel along each
michael@0:  *  axis. Thus we can treat an axis coordinate as an integer if it differs
michael@0:  *  from its nearest int by < half of that value (1.8 in this case).
michael@0:  */
michael@0: static bool nearly_integral(SkScalar x) {
michael@0:     static const SkScalar domain = SK_Scalar1 / 4;
michael@0:     static const SkScalar halfDomain = domain / 2;
michael@0: 
michael@0:     x += halfDomain;
michael@0:     return x - SkScalarFloorToScalar(x) < domain;
michael@0: }
michael@0: 
michael@0: bool SkRasterClip::op(const SkRect& r, SkRegion::Op op, bool doAA) {
michael@0:     AUTO_RASTERCLIP_VALIDATE(*this);
michael@0: 
michael@0:     if (fIsBW && doAA) {
michael@0:         // check that the rect really needs aa, or is it close enought to
michael@0:         // integer boundaries that we can just treat it as a BW rect?
michael@0:         if (nearly_integral(r.fLeft) && nearly_integral(r.fTop) &&
michael@0:             nearly_integral(r.fRight) && nearly_integral(r.fBottom)) {
michael@0:             doAA = false;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     if (fIsBW && !doAA) {
michael@0:         SkIRect ir;
michael@0:         r.round(&ir);
michael@0:         (void)fBW.op(ir, op);
michael@0:     } else {
michael@0:         if (fIsBW) {
michael@0:             this->convertToAA();
michael@0:         }
michael@0:         (void)fAA.op(r, op, doAA);
michael@0:     }
michael@0:     return this->updateCacheAndReturnNonEmpty();
michael@0: }
michael@0: 
michael@0: void SkRasterClip::translate(int dx, int dy, SkRasterClip* dst) const {
michael@0:     if (NULL == dst) {
michael@0:         return;
michael@0:     }
michael@0: 
michael@0:     AUTO_RASTERCLIP_VALIDATE(*this);
michael@0: 
michael@0:     if (this->isEmpty()) {
michael@0:         dst->setEmpty();
michael@0:         return;
michael@0:     }
michael@0:     if (0 == (dx | dy)) {
michael@0:         *dst = *this;
michael@0:         return;
michael@0:     }
michael@0: 
michael@0:     dst->fIsBW = fIsBW;
michael@0:     if (fIsBW) {
michael@0:         fBW.translate(dx, dy, &dst->fBW);
michael@0:         dst->fAA.setEmpty();
michael@0:     } else {
michael@0:         fAA.translate(dx, dy, &dst->fAA);
michael@0:         dst->fBW.setEmpty();
michael@0:     }
michael@0:     dst->updateCacheAndReturnNonEmpty();
michael@0: }
michael@0: 
michael@0: bool SkRasterClip::quickContains(const SkIRect& ir) const {
michael@0:     return fIsBW ? fBW.quickContains(ir) : fAA.quickContains(ir);
michael@0: }
michael@0: 
michael@0: ///////////////////////////////////////////////////////////////////////////////
michael@0: 
michael@0: const SkRegion& SkRasterClip::forceGetBW() {
michael@0:     AUTO_RASTERCLIP_VALIDATE(*this);
michael@0: 
michael@0:     if (!fIsBW) {
michael@0:         fBW.setRect(fAA.getBounds());
michael@0:     }
michael@0:     return fBW;
michael@0: }
michael@0: 
michael@0: void SkRasterClip::convertToAA() {
michael@0:     AUTO_RASTERCLIP_VALIDATE(*this);
michael@0: 
michael@0:     SkASSERT(fIsBW);
michael@0:     fAA.setRegion(fBW);
michael@0:     fIsBW = false;
michael@0:     (void)this->updateCacheAndReturnNonEmpty();
michael@0: }
michael@0: 
michael@0: #ifdef SK_DEBUG
michael@0: void SkRasterClip::validate() const {
michael@0:     // can't ever assert that fBW is empty, since we may have called forceGetBW
michael@0:     if (fIsBW) {
michael@0:         SkASSERT(fAA.isEmpty());
michael@0:     }
michael@0: 
michael@0:     fBW.validate();
michael@0:     fAA.validate();
michael@0: 
michael@0:     SkASSERT(this->computeIsEmpty() == fIsEmpty);
michael@0:     SkASSERT(this->computeIsRect() == fIsRect);
michael@0: }
michael@0: #endif
michael@0: 
michael@0: ///////////////////////////////////////////////////////////////////////////////
michael@0: 
michael@0: SkAAClipBlitterWrapper::SkAAClipBlitterWrapper() {
michael@0:     SkDEBUGCODE(fClipRgn = NULL;)
michael@0:     SkDEBUGCODE(fBlitter = NULL;)
michael@0: }
michael@0: 
michael@0: SkAAClipBlitterWrapper::SkAAClipBlitterWrapper(const SkRasterClip& clip,
michael@0:                                                SkBlitter* blitter) {
michael@0:     this->init(clip, blitter);
michael@0: }
michael@0: 
michael@0: SkAAClipBlitterWrapper::SkAAClipBlitterWrapper(const SkAAClip* aaclip,
michael@0:                                                SkBlitter* blitter) {
michael@0:     SkASSERT(blitter);
michael@0:     SkASSERT(aaclip);
michael@0:     fBWRgn.setRect(aaclip->getBounds());
michael@0:     fAABlitter.init(blitter, aaclip);
michael@0:     // now our return values
michael@0:     fClipRgn = &fBWRgn;
michael@0:     fBlitter = &fAABlitter;
michael@0: }
michael@0: 
michael@0: void SkAAClipBlitterWrapper::init(const SkRasterClip& clip, SkBlitter* blitter) {
michael@0:     SkASSERT(blitter);
michael@0:     if (clip.isBW()) {
michael@0:         fClipRgn = &clip.bwRgn();
michael@0:         fBlitter = blitter;
michael@0:     } else {
michael@0:         const SkAAClip& aaclip = clip.aaRgn();
michael@0:         fBWRgn.setRect(aaclip.getBounds());
michael@0:         fAABlitter.init(blitter, &aaclip);
michael@0:         // now our return values
michael@0:         fClipRgn = &fBWRgn;
michael@0:         fBlitter = &fAABlitter;
michael@0:     }
michael@0: }