/*
* Copyright 2011 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkCanvas.h"
#include "SkClipStack.h"
#include "SkPath.h"
#include "SkPathOps.h"
#include "SkClipOpPriv.h"
#include <atomic>
#include <new>
#if SK_SUPPORT_GPU
#include "GrProxyProvider.h"
#endif
SkClipStack::Element::Element(const Element& that) {
switch (that.getDeviceSpaceType()) {
case DeviceSpaceType::kEmpty:
fDeviceSpaceRRect.setEmpty();
fDeviceSpacePath.reset();
break;
case DeviceSpaceType::kRect: // Rect uses rrect
case DeviceSpaceType::kRRect:
fDeviceSpacePath.reset();
fDeviceSpaceRRect = that.fDeviceSpaceRRect;
break;
case DeviceSpaceType::kPath:
fDeviceSpacePath.set(that.getDeviceSpacePath());
break;
}
fSaveCount = that.fSaveCount;
fOp = that.fOp;
fDeviceSpaceType = that.fDeviceSpaceType;
fDoAA = that.fDoAA;
fFiniteBoundType = that.fFiniteBoundType;
fFiniteBound = that.fFiniteBound;
fIsIntersectionOfRects = that.fIsIntersectionOfRects;
fGenID = that.fGenID;
}
SkClipStack::Element::~Element() {
#if SK_SUPPORT_GPU
for (int i = 0; i < fKeysToInvalidate.count(); ++i) {
fProxyProvider->processInvalidUniqueKey(fKeysToInvalidate[i], nullptr,
GrProxyProvider::InvalidateGPUResource::kYes);
}
#endif
}
bool SkClipStack::Element::operator== (const Element& element) const {
if (this == &element) {
return true;
}
if (fOp != element.fOp || fDeviceSpaceType != element.fDeviceSpaceType ||
fDoAA != element.fDoAA || fSaveCount != element.fSaveCount) {
return false;
}
switch (fDeviceSpaceType) {
case DeviceSpaceType::kPath:
return this->getDeviceSpacePath() == element.getDeviceSpacePath();
case DeviceSpaceType::kRRect:
return fDeviceSpaceRRect == element.fDeviceSpaceRRect;
case DeviceSpaceType::kRect:
return this->getDeviceSpaceRect() == element.getDeviceSpaceRect();
case DeviceSpaceType::kEmpty:
return true;
default:
SkDEBUGFAIL("Unexpected type.");
return false;
}
}
const SkRect& SkClipStack::Element::getBounds() const {
static const SkRect kEmpty = {0, 0, 0, 0};
switch (fDeviceSpaceType) {
case DeviceSpaceType::kRect: // fallthrough
case DeviceSpaceType::kRRect:
return fDeviceSpaceRRect.getBounds();
case DeviceSpaceType::kPath:
return fDeviceSpacePath.get()->getBounds();
case DeviceSpaceType::kEmpty:
return kEmpty;
default:
SkDEBUGFAIL("Unexpected type.");
return kEmpty;
}
}
bool SkClipStack::Element::contains(const SkRect& rect) const {
switch (fDeviceSpaceType) {
case DeviceSpaceType::kRect:
return this->getDeviceSpaceRect().contains(rect);
case DeviceSpaceType::kRRect:
return fDeviceSpaceRRect.contains(rect);
case DeviceSpaceType::kPath:
return fDeviceSpacePath.get()->conservativelyContainsRect(rect);
case DeviceSpaceType::kEmpty:
return false;
default:
SkDEBUGFAIL("Unexpected type.");
return false;
}
}
bool SkClipStack::Element::contains(const SkRRect& rrect) const {
switch (fDeviceSpaceType) {
case DeviceSpaceType::kRect:
return this->getDeviceSpaceRect().contains(rrect.getBounds());
case DeviceSpaceType::kRRect:
// We don't currently have a generalized rrect-rrect containment.
return fDeviceSpaceRRect.contains(rrect.getBounds()) || rrect == fDeviceSpaceRRect;
case DeviceSpaceType::kPath:
return fDeviceSpacePath.get()->conservativelyContainsRect(rrect.getBounds());
case DeviceSpaceType::kEmpty:
return false;
default:
SkDEBUGFAIL("Unexpected type.");
return false;
}
}
void SkClipStack::Element::invertShapeFillType() {
switch (fDeviceSpaceType) {
case DeviceSpaceType::kRect:
fDeviceSpacePath.init();
fDeviceSpacePath.get()->addRect(this->getDeviceSpaceRect());
fDeviceSpacePath.get()->setFillType(SkPath::kInverseEvenOdd_FillType);
fDeviceSpaceType = DeviceSpaceType::kPath;
break;
case DeviceSpaceType::kRRect:
fDeviceSpacePath.init();
fDeviceSpacePath.get()->addRRect(fDeviceSpaceRRect);
fDeviceSpacePath.get()->setFillType(SkPath::kInverseEvenOdd_FillType);
fDeviceSpaceType = DeviceSpaceType::kPath;
break;
case DeviceSpaceType::kPath:
fDeviceSpacePath.get()->toggleInverseFillType();
break;
case DeviceSpaceType::kEmpty:
// Should this set to an empty, inverse filled path?
break;
}
}
void SkClipStack::Element::initCommon(int saveCount, SkClipOp op, bool doAA) {
fSaveCount = saveCount;
fOp = op;
fDoAA = doAA;
// A default of inside-out and empty bounds means the bounds are effectively void as it
// indicates that nothing is known to be outside the clip.
fFiniteBoundType = kInsideOut_BoundsType;
fFiniteBound.setEmpty();
fIsIntersectionOfRects = false;
fGenID = kInvalidGenID;
}
void SkClipStack::Element::initRect(int saveCount, const SkRect& rect, const SkMatrix& m,
SkClipOp op, bool doAA) {
if (m.rectStaysRect()) {
SkRect devRect;
m.mapRect(&devRect, rect);
fDeviceSpaceRRect.setRect(devRect);
fDeviceSpaceType = DeviceSpaceType::kRect;
this->initCommon(saveCount, op, doAA);
return;
}
SkPath path;
path.addRect(rect);
path.setIsVolatile(true);
this->initAsPath(saveCount, path, m, op, doAA);
}
void SkClipStack::Element::initRRect(int saveCount, const SkRRect& rrect, const SkMatrix& m,
SkClipOp op, bool doAA) {
if (rrect.transform(m, &fDeviceSpaceRRect)) {
SkRRect::Type type = fDeviceSpaceRRect.getType();
if (SkRRect::kRect_Type == type || SkRRect::kEmpty_Type == type) {
fDeviceSpaceType = DeviceSpaceType::kRect;
} else {
fDeviceSpaceType = DeviceSpaceType::kRRect;
}
this->initCommon(saveCount, op, doAA);
return;
}
SkPath path;
path.addRRect(rrect);
path.setIsVolatile(true);
this->initAsPath(saveCount, path, m, op, doAA);
}
void SkClipStack::Element::initPath(int saveCount, const SkPath& path, const SkMatrix& m,
SkClipOp op, bool doAA) {
if (!path.isInverseFillType()) {
SkRect r;
if (path.isRect(&r)) {
this->initRect(saveCount, r, m, op, doAA);
return;
}
SkRect ovalRect;
if (path.isOval(&ovalRect)) {
SkRRect rrect;
rrect.setOval(ovalRect);
this->initRRect(saveCount, rrect, m, op, doAA);
return;
}
}
this->initAsPath(saveCount, path, m, op, doAA);
}
void SkClipStack::Element::initAsPath(int saveCount, const SkPath& path, const SkMatrix& m,
SkClipOp op, bool doAA) {
path.transform(m, fDeviceSpacePath.init());
fDeviceSpacePath.get()->setIsVolatile(true);
fDeviceSpaceType = DeviceSpaceType::kPath;
this->initCommon(saveCount, op, doAA);
}
void SkClipStack::Element::asDeviceSpacePath(SkPath* path) const {
switch (fDeviceSpaceType) {
case DeviceSpaceType::kEmpty:
path->reset();
break;
case DeviceSpaceType::kRect:
path->reset();
path->addRect(this->getDeviceSpaceRect());
break;
case DeviceSpaceType::kRRect:
path->reset();
path->addRRect(fDeviceSpaceRRect);
break;
case DeviceSpaceType::kPath:
*path = *fDeviceSpacePath.get();
break;
}
path->setIsVolatile(true);
}
void SkClipStack::Element::setEmpty() {
fDeviceSpaceType = DeviceSpaceType::kEmpty;
fFiniteBound.setEmpty();
fFiniteBoundType = kNormal_BoundsType;
fIsIntersectionOfRects = false;
fDeviceSpaceRRect.setEmpty();
fDeviceSpacePath.reset();
fGenID = kEmptyGenID;
SkDEBUGCODE(this->checkEmpty();)
}
void SkClipStack::Element::checkEmpty() const {
SkASSERT(fFiniteBound.isEmpty());
SkASSERT(kNormal_BoundsType == fFiniteBoundType);
SkASSERT(!fIsIntersectionOfRects);
SkASSERT(kEmptyGenID == fGenID);
SkASSERT(fDeviceSpaceRRect.isEmpty());
SkASSERT(!fDeviceSpacePath.isValid());
}
bool SkClipStack::Element::canBeIntersectedInPlace(int saveCount, SkClipOp op) const {
if (DeviceSpaceType::kEmpty == fDeviceSpaceType &&
(kDifference_SkClipOp == op || kIntersect_SkClipOp == op)) {
return true;
}
// Only clips within the same save/restore frame (as captured by
// the save count) can be merged
return fSaveCount == saveCount &&
kIntersect_SkClipOp == op &&
(kIntersect_SkClipOp == fOp || kReplace_SkClipOp == fOp);
}
bool SkClipStack::Element::rectRectIntersectAllowed(const SkRect& newR, bool newAA) const {
SkASSERT(DeviceSpaceType::kRect == fDeviceSpaceType);
if (fDoAA == newAA) {
// if the AA setting is the same there is no issue
return true;
}
if (!SkRect::Intersects(this->getDeviceSpaceRect(), newR)) {
// The calling code will correctly set the result to the empty clip
return true;
}
if (this->getDeviceSpaceRect().contains(newR)) {
// if the new rect carves out a portion of the old one there is no
// issue
return true;
}
// So either the two overlap in some complex manner or newR contains oldR.
// In the first, case the edges will require different AA. In the second,
// the AA setting that would be carried forward is incorrect (e.g., oldR
// is AA while newR is BW but since newR contains oldR, oldR will be
// drawn BW) since the new AA setting will predominate.
return false;
}
// a mirror of combineBoundsRevDiff
void SkClipStack::Element::combineBoundsDiff(FillCombo combination, const SkRect& prevFinite) {
switch (combination) {
case kInvPrev_InvCur_FillCombo:
// In this case the only pixels that can remain set
// are inside the current clip rect since the extensions
// to infinity of both clips cancel out and whatever
// is outside of the current clip is removed
fFiniteBoundType = kNormal_BoundsType;
break;
case kInvPrev_Cur_FillCombo:
// In this case the current op is finite so the only pixels
// that aren't set are whatever isn't set in the previous
// clip and whatever this clip carves out
fFiniteBound.join(prevFinite);
fFiniteBoundType = kInsideOut_BoundsType;
break;
case kPrev_InvCur_FillCombo:
// In this case everything outside of this clip's bound
// is erased, so the only pixels that can remain set
// occur w/in the intersection of the two finite bounds
if (!fFiniteBound.intersect(prevFinite)) {
fFiniteBound.setEmpty();
fGenID = kEmptyGenID;
}
fFiniteBoundType = kNormal_BoundsType;
break;
case kPrev_Cur_FillCombo:
// The most conservative result bound is that of the
// prior clip. This could be wildly incorrect if the
// second clip either exactly matches the first clip
// (which should yield the empty set) or reduces the
// size of the prior bound (e.g., if the second clip
// exactly matched the bottom half of the prior clip).
// We ignore these two possibilities.
fFiniteBound = prevFinite;
break;
default:
SkDEBUGFAIL("SkClipStack::Element::combineBoundsDiff Invalid fill combination");
break;
}
}
void SkClipStack::Element::combineBoundsXOR(int combination, const SkRect& prevFinite) {
switch (combination) {
case kInvPrev_Cur_FillCombo: // fall through
case kPrev_InvCur_FillCombo:
// With only one of the clips inverted the result will always
// extend to infinity. The only pixels that may be un-writeable
// lie within the union of the two finite bounds
fFiniteBound.join(prevFinite);
fFiniteBoundType = kInsideOut_BoundsType;
break;
case kInvPrev_InvCur_FillCombo:
// The only pixels that can survive are within the
// union of the two bounding boxes since the extensions
// to infinity of both clips cancel out
// fall through!
case kPrev_Cur_FillCombo:
// The most conservative bound for xor is the
// union of the two bounds. If the two clips exactly overlapped
// the xor could yield the empty set. Similarly the xor
// could reduce the size of the original clip's bound (e.g.,
// if the second clip exactly matched the bottom half of the
// first clip). We ignore these two cases.
fFiniteBound.join(prevFinite);
fFiniteBoundType = kNormal_BoundsType;
break;
default:
SkDEBUGFAIL("SkClipStack::Element::combineBoundsXOR Invalid fill combination");
break;
}
}
// a mirror of combineBoundsIntersection
void SkClipStack::Element::combineBoundsUnion(int combination, const SkRect& prevFinite) {
switch (combination) {
case kInvPrev_InvCur_FillCombo:
if (!fFiniteBound.intersect(prevFinite)) {
fFiniteBound.setEmpty();
fGenID = kWideOpenGenID;
}
fFiniteBoundType = kInsideOut_BoundsType;
break;
case kInvPrev_Cur_FillCombo:
// The only pixels that won't be drawable are inside
// the prior clip's finite bound
fFiniteBound = prevFinite;
fFiniteBoundType = kInsideOut_BoundsType;
break;
case kPrev_InvCur_FillCombo:
// The only pixels that won't be drawable are inside
// this clip's finite bound
break;
case kPrev_Cur_FillCombo:
fFiniteBound.join(prevFinite);
break;
default:
SkDEBUGFAIL("SkClipStack::Element::combineBoundsUnion Invalid fill combination");
break;
}
}
// a mirror of combineBoundsUnion
void SkClipStack::Element::combineBoundsIntersection(int combination, const SkRect& prevFinite) {
switch (combination) {
case kInvPrev_InvCur_FillCombo:
// The only pixels that aren't writable in this case
// occur in the union of the two finite bounds
fFiniteBound.join(prevFinite);
fFiniteBoundType = kInsideOut_BoundsType;
break;
case kInvPrev_Cur_FillCombo:
// In this case the only pixels that will remain writeable
// are within the current clip
break;
case kPrev_InvCur_FillCombo:
// In this case the only pixels that will remain writeable
// are with the previous clip
fFiniteBound = prevFinite;
fFiniteBoundType = kNormal_BoundsType;
break;
case kPrev_Cur_FillCombo:
if (!fFiniteBound.intersect(prevFinite)) {
this->setEmpty();
}
break;
default:
SkDEBUGFAIL("SkClipStack::Element::combineBoundsIntersection Invalid fill combination");
break;
}
}
// a mirror of combineBoundsDiff
void SkClipStack::Element::combineBoundsRevDiff(int combination, const SkRect& prevFinite) {
switch (combination) {
case kInvPrev_InvCur_FillCombo:
// The only pixels that can survive are in the
// previous bound since the extensions to infinity in
// both clips cancel out
fFiniteBound = prevFinite;
fFiniteBoundType = kNormal_BoundsType;
break;
case kInvPrev_Cur_FillCombo:
if (!fFiniteBound.intersect(prevFinite)) {
this->setEmpty();
} else {
fFiniteBoundType = kNormal_BoundsType;
}
break;
case kPrev_InvCur_FillCombo:
fFiniteBound.join(prevFinite);
fFiniteBoundType = kInsideOut_BoundsType;
break;
case kPrev_Cur_FillCombo:
// Fall through - as with the kDifference_Op case, the
// most conservative result bound is the bound of the
// current clip. The prior clip could reduce the size of this
// bound (as in the kDifference_Op case) but we are ignoring
// those cases.
break;
default:
SkDEBUGFAIL("SkClipStack::Element::combineBoundsRevDiff Invalid fill combination");
break;
}
}
void SkClipStack::Element::updateBoundAndGenID(const Element* prior) {
// We set this first here but we may overwrite it later if we determine that the clip is
// either wide-open or empty.
fGenID = GetNextGenID();
// First, optimistically update the current Element's bound information
// with the current clip's bound
fIsIntersectionOfRects = false;
switch (fDeviceSpaceType) {
case DeviceSpaceType::kRect:
fFiniteBound = this->getDeviceSpaceRect();
fFiniteBoundType = kNormal_BoundsType;
if (kReplace_SkClipOp == fOp || (kIntersect_SkClipOp == fOp && nullptr == prior) ||
(kIntersect_SkClipOp == fOp && prior->fIsIntersectionOfRects &&
prior->rectRectIntersectAllowed(this->getDeviceSpaceRect(), fDoAA))) {
fIsIntersectionOfRects = true;
}
break;
case DeviceSpaceType::kRRect:
fFiniteBound = fDeviceSpaceRRect.getBounds();
fFiniteBoundType = kNormal_BoundsType;
break;
case DeviceSpaceType::kPath:
fFiniteBound = fDeviceSpacePath.get()->getBounds();
if (fDeviceSpacePath.get()->isInverseFillType()) {
fFiniteBoundType = kInsideOut_BoundsType;
} else {
fFiniteBoundType = kNormal_BoundsType;
}
break;
case DeviceSpaceType::kEmpty:
SkDEBUGFAIL("We shouldn't get here with an empty element.");
break;
}
// Now determine the previous Element's bound information taking into
// account that there may be no previous clip
SkRect prevFinite;
SkClipStack::BoundsType prevType;
if (nullptr == prior) {
// no prior clip means the entire plane is writable
prevFinite.setEmpty(); // there are no pixels that cannot be drawn to
prevType = kInsideOut_BoundsType;
} else {
prevFinite = prior->fFiniteBound;
prevType = prior->fFiniteBoundType;
}
FillCombo combination = kPrev_Cur_FillCombo;
if (kInsideOut_BoundsType == fFiniteBoundType) {
combination = (FillCombo) (combination | 0x01);
}
if (kInsideOut_BoundsType == prevType) {
combination = (FillCombo) (combination | 0x02);
}
SkASSERT(kInvPrev_InvCur_FillCombo == combination ||
kInvPrev_Cur_FillCombo == combination ||
kPrev_InvCur_FillCombo == combination ||
kPrev_Cur_FillCombo == combination);
// Now integrate with clip with the prior clips
switch (fOp) {
case kDifference_SkClipOp:
this->combineBoundsDiff(combination, prevFinite);
break;
case kXOR_SkClipOp:
this->combineBoundsXOR(combination, prevFinite);
break;
case kUnion_SkClipOp:
this->combineBoundsUnion(combination, prevFinite);
break;
case kIntersect_SkClipOp:
this->combineBoundsIntersection(combination, prevFinite);
break;
case kReverseDifference_SkClipOp:
this->combineBoundsRevDiff(combination, prevFinite);
break;
case kReplace_SkClipOp:
// Replace just ignores everything prior
// The current clip's bound information is already filled in
// so nothing to do
break;
default:
SkDebugf("SkClipOp error\n");
SkASSERT(0);
break;
}
}
// This constant determines how many Element's are allocated together as a block in
// the deque. As such it needs to balance allocating too much memory vs.
// incurring allocation/deallocation thrashing. It should roughly correspond to
// the deepest save/restore stack we expect to see.
static const int kDefaultElementAllocCnt = 8;
SkClipStack::SkClipStack()
: fDeque(sizeof(Element), kDefaultElementAllocCnt)
, fSaveCount(0) {
}
SkClipStack::SkClipStack(void* storage, size_t size)
: fDeque(sizeof(Element), storage, size, kDefaultElementAllocCnt)
, fSaveCount(0) {
}
SkClipStack::SkClipStack(const SkClipStack& b)
: fDeque(sizeof(Element), kDefaultElementAllocCnt) {
*this = b;
}
SkClipStack::~SkClipStack() {
reset();
}
SkClipStack& SkClipStack::operator=(const SkClipStack& b) {
if (this == &b) {
return *this;
}
reset();
fSaveCount = b.fSaveCount;
SkDeque::F2BIter recIter(b.fDeque);
for (const Element* element = (const Element*)recIter.next();
element != nullptr;
element = (const Element*)recIter.next()) {
new (fDeque.push_back()) Element(*element);
}
return *this;
}
bool SkClipStack::operator==(const SkClipStack& b) const {
if (this->getTopmostGenID() == b.getTopmostGenID()) {
return true;
}
if (fSaveCount != b.fSaveCount ||
fDeque.count() != b.fDeque.count()) {
return false;
}
SkDeque::F2BIter myIter(fDeque);
SkDeque::F2BIter bIter(b.fDeque);
const Element* myElement = (const Element*)myIter.next();
const Element* bElement = (const Element*)bIter.next();
while (myElement != nullptr && bElement != nullptr) {
if (*myElement != *bElement) {
return false;
}
myElement = (const Element*)myIter.next();
bElement = (const Element*)bIter.next();
}
return myElement == nullptr && bElement == nullptr;
}
void SkClipStack::reset() {
// We used a placement new for each object in fDeque, so we're responsible
// for calling the destructor on each of them as well.
while (!fDeque.empty()) {
Element* element = (Element*)fDeque.back();
element->~Element();
fDeque.pop_back();
}
fSaveCount = 0;
}
void SkClipStack::save() {
fSaveCount += 1;
}
void SkClipStack::restore() {
fSaveCount -= 1;
restoreTo(fSaveCount);
}
void SkClipStack::restoreTo(int saveCount) {
while (!fDeque.empty()) {
Element* element = (Element*)fDeque.back();
if (element->fSaveCount <= saveCount) {
break;
}
element->~Element();
fDeque.pop_back();
}
}
SkRect SkClipStack::bounds(const SkIRect& deviceBounds) const {
// TODO: optimize this.
SkRect r;
SkClipStack::BoundsType bounds;
this->getBounds(&r, &bounds);
if (bounds == SkClipStack::kInsideOut_BoundsType) {
return SkRect::Make(deviceBounds);
}
return r.intersect(SkRect::Make(deviceBounds)) ? r : SkRect::MakeEmpty();
}
// TODO: optimize this.
bool SkClipStack::isEmpty(const SkIRect& r) const { return this->bounds(r).isEmpty(); }
void SkClipStack::getBounds(SkRect* canvFiniteBound,
BoundsType* boundType,
bool* isIntersectionOfRects) const {
SkASSERT(canvFiniteBound && boundType);
Element* element = (Element*)fDeque.back();
if (nullptr == element) {
// the clip is wide open - the infinite plane w/ no pixels un-writeable
canvFiniteBound->setEmpty();
*boundType = kInsideOut_BoundsType;
if (isIntersectionOfRects) {
*isIntersectionOfRects = false;
}
return;
}
*canvFiniteBound = element->fFiniteBound;
*boundType = element->fFiniteBoundType;
if (isIntersectionOfRects) {
*isIntersectionOfRects = element->fIsIntersectionOfRects;
}
}
bool SkClipStack::internalQuickContains(const SkRect& rect) const {
Iter iter(*this, Iter::kTop_IterStart);
const Element* element = iter.prev();
while (element != nullptr) {
if (kIntersect_SkClipOp != element->getOp() && kReplace_SkClipOp != element->getOp())
return false;
if (element->isInverseFilled()) {
// Part of 'rect' could be trimmed off by the inverse-filled clip element
if (SkRect::Intersects(element->getBounds(), rect)) {
return false;
}
} else {
if (!element->contains(rect)) {
return false;
}
}
if (kReplace_SkClipOp == element->getOp()) {
break;
}
element = iter.prev();
}
return true;
}
bool SkClipStack::internalQuickContains(const SkRRect& rrect) const {
Iter iter(*this, Iter::kTop_IterStart);
const Element* element = iter.prev();
while (element != nullptr) {
if (kIntersect_SkClipOp != element->getOp() && kReplace_SkClipOp != element->getOp())
return false;
if (element->isInverseFilled()) {
// Part of 'rrect' could be trimmed off by the inverse-filled clip element
if (SkRect::Intersects(element->getBounds(), rrect.getBounds())) {
return false;
}
} else {
if (!element->contains(rrect)) {
return false;
}
}
if (kReplace_SkClipOp == element->getOp()) {
break;
}
element = iter.prev();
}
return true;
}
bool SkClipStack::asPath(SkPath *path) const {
bool isAA = false;
path->reset();
path->setFillType(SkPath::kInverseEvenOdd_FillType);
SkClipStack::Iter iter(*this, SkClipStack::Iter::kBottom_IterStart);
while (const SkClipStack::Element* element = iter.next()) {
SkPath operand;
if (element->getDeviceSpaceType() != SkClipStack::Element::DeviceSpaceType::kEmpty) {
element->asDeviceSpacePath(&operand);
}
SkClipOp elementOp = element->getOp();
if (elementOp == kReplace_SkClipOp) {
*path = operand;
} else {
Op(*path, operand, (SkPathOp)elementOp, path);
}
// if the prev and curr clips disagree about aa -vs- not, favor the aa request.
// perhaps we need an API change to avoid this sort of mixed-signals about
// clipping.
isAA = (isAA || element->isAA());
}
return isAA;
}
void SkClipStack::pushElement(const Element& element) {
// Use reverse iterator instead of back because Rect path may need previous
SkDeque::Iter iter(fDeque, SkDeque::Iter::kBack_IterStart);
Element* prior = (Element*) iter.prev();
if (prior) {
if (prior->canBeIntersectedInPlace(fSaveCount, element.getOp())) {
switch (prior->fDeviceSpaceType) {
case Element::DeviceSpaceType::kEmpty:
SkDEBUGCODE(prior->checkEmpty();)
return;
case Element::DeviceSpaceType::kRect:
if (Element::DeviceSpaceType::kRect == element.getDeviceSpaceType()) {
if (prior->rectRectIntersectAllowed(element.getDeviceSpaceRect(),
element.isAA())) {
SkRect isectRect;
if (!isectRect.intersect(prior->getDeviceSpaceRect(),
element.getDeviceSpaceRect())) {
prior->setEmpty();
return;
}
prior->fDeviceSpaceRRect.setRect(isectRect);
prior->fDoAA = element.isAA();
Element* priorPrior = (Element*) iter.prev();
prior->updateBoundAndGenID(priorPrior);
return;
}
break;
}
// fallthrough
default:
if (!SkRect::Intersects(prior->getBounds(), element.getBounds())) {
prior->setEmpty();
return;
}
break;
}
} else if (kReplace_SkClipOp == element.getOp()) {
this->restoreTo(fSaveCount - 1);
prior = (Element*) fDeque.back();
}
}
Element* newElement = new (fDeque.push_back()) Element(element);
newElement->updateBoundAndGenID(prior);
}
void SkClipStack::clipRRect(const SkRRect& rrect, const SkMatrix& matrix, SkClipOp op,
bool doAA) {
Element element(fSaveCount, rrect, matrix, op, doAA);
this->pushElement(element);
if (this->hasClipRestriction(op)) {
Element restriction(fSaveCount, fClipRestrictionRect, SkMatrix::I(), kIntersect_SkClipOp,
false);
this->pushElement(restriction);
}
}
void SkClipStack::clipRect(const SkRect& rect, const SkMatrix& matrix, SkClipOp op,
bool doAA) {
Element element(fSaveCount, rect, matrix, op, doAA);
this->pushElement(element);
if (this->hasClipRestriction(op)) {
Element restriction(fSaveCount, fClipRestrictionRect, SkMatrix::I(), kIntersect_SkClipOp,
false);
this->pushElement(restriction);
}
}
void SkClipStack::clipPath(const SkPath& path, const SkMatrix& matrix, SkClipOp op,
bool doAA) {
Element element(fSaveCount, path, matrix, op, doAA);
this->pushElement(element);
if (this->hasClipRestriction(op)) {
Element restriction(fSaveCount, fClipRestrictionRect, SkMatrix::I(), kIntersect_SkClipOp,
false);
this->pushElement(restriction);
}
}
void SkClipStack::clipEmpty() {
Element* element = (Element*) fDeque.back();
if (element && element->canBeIntersectedInPlace(fSaveCount, kIntersect_SkClipOp)) {
element->setEmpty();
}
new (fDeque.push_back()) Element(fSaveCount);
((Element*)fDeque.back())->fGenID = kEmptyGenID;
}
///////////////////////////////////////////////////////////////////////////////
SkClipStack::Iter::Iter() : fStack(nullptr) {
}
SkClipStack::Iter::Iter(const SkClipStack& stack, IterStart startLoc)
: fStack(&stack) {
this->reset(stack, startLoc);
}
const SkClipStack::Element* SkClipStack::Iter::next() {
return (const SkClipStack::Element*)fIter.next();
}
const SkClipStack::Element* SkClipStack::Iter::prev() {
return (const SkClipStack::Element*)fIter.prev();
}
const SkClipStack::Element* SkClipStack::Iter::skipToTopmost(SkClipOp op) {
if (nullptr == fStack) {
return nullptr;
}
fIter.reset(fStack->fDeque, SkDeque::Iter::kBack_IterStart);
const SkClipStack::Element* element = nullptr;
for (element = (const SkClipStack::Element*) fIter.prev();
element;
element = (const SkClipStack::Element*) fIter.prev()) {
if (op == element->fOp) {
// The Deque's iterator is actually one pace ahead of the
// returned value. So while "element" is the element we want to
// return, the iterator is actually pointing at (and will
// return on the next "next" or "prev" call) the element
// in front of it in the deque. Bump the iterator forward a
// step so we get the expected result.
if (nullptr == fIter.next()) {
// The reverse iterator has run off the front of the deque
// (i.e., the "op" clip is the first clip) and can't
// recover. Reset the iterator to start at the front.
fIter.reset(fStack->fDeque, SkDeque::Iter::kFront_IterStart);
}
break;
}
}
if (nullptr == element) {
// There were no "op" clips
fIter.reset(fStack->fDeque, SkDeque::Iter::kFront_IterStart);
}
return this->next();
}
void SkClipStack::Iter::reset(const SkClipStack& stack, IterStart startLoc) {
fStack = &stack;
fIter.reset(stack.fDeque, static_cast<SkDeque::Iter::IterStart>(startLoc));
}
// helper method
void SkClipStack::getConservativeBounds(int offsetX,
int offsetY,
int maxWidth,
int maxHeight,
SkRect* devBounds,
bool* isIntersectionOfRects) const {
SkASSERT(devBounds);
devBounds->setLTRB(0, 0,
SkIntToScalar(maxWidth), SkIntToScalar(maxHeight));
SkRect temp;
SkClipStack::BoundsType boundType;
// temp starts off in canvas space here
this->getBounds(&temp, &boundType, isIntersectionOfRects);
if (SkClipStack::kInsideOut_BoundsType == boundType) {
return;
}
// but is converted to device space here
temp.offset(SkIntToScalar(offsetX), SkIntToScalar(offsetY));
if (!devBounds->intersect(temp)) {
devBounds->setEmpty();
}
}
bool SkClipStack::isRRect(const SkRect& bounds, SkRRect* rrect, bool* aa) const {
const Element* back = static_cast<const Element*>(fDeque.back());
if (!back) {
// TODO: return bounds?
return false;
}
// First check if the entire stack is known to be a rect by the top element.
if (back->fIsIntersectionOfRects && back->fFiniteBoundType == BoundsType::kNormal_BoundsType) {
rrect->setRect(back->fFiniteBound);
*aa = back->isAA();
return true;
}
if (back->getDeviceSpaceType() != SkClipStack::Element::DeviceSpaceType::kRect &&
back->getDeviceSpaceType() != SkClipStack::Element::DeviceSpaceType::kRRect) {
return false;
}
if (back->getOp() == kReplace_SkClipOp) {
*rrect = back->asDeviceSpaceRRect();
*aa = back->isAA();
return true;
}
if (back->getOp() == kIntersect_SkClipOp) {
SkRect backBounds;
if (!backBounds.intersect(bounds, back->asDeviceSpaceRRect().rect())) {
return false;
}
// We limit to 5 elements. This means the back element will be bounds checked at most 4
// times if it is an rrect.
int cnt = fDeque.count();
if (cnt > 5) {
return false;
}
if (cnt > 1) {
SkDeque::Iter iter(fDeque, SkDeque::Iter::kBack_IterStart);
SkAssertResult(static_cast<const Element*>(iter.prev()) == back);
while (const Element* prior = (const Element*)iter.prev()) {
if ((prior->getOp() != kIntersect_SkClipOp &&
prior->getOp() != kReplace_SkClipOp) ||
!prior->contains(backBounds)) {
return false;
}
if (prior->getOp() == kReplace_SkClipOp) {
break;
}
}
}
*rrect = back->asDeviceSpaceRRect();
*aa = back->isAA();
return true;
}
return false;
}
uint32_t SkClipStack::GetNextGenID() {
// 0-2 are reserved for invalid, empty & wide-open
static const uint32_t kFirstUnreservedGenID = 3;
static std::atomic<uint32_t> nextID{kFirstUnreservedGenID};
uint32_t id;
do {
id = nextID++;
} while (id < kFirstUnreservedGenID);
return id;
}
uint32_t SkClipStack::getTopmostGenID() const {
if (fDeque.empty()) {
return kWideOpenGenID;
}
const Element* back = static_cast<const Element*>(fDeque.back());
if (kInsideOut_BoundsType == back->fFiniteBoundType && back->fFiniteBound.isEmpty()) {
return kWideOpenGenID;
}
return back->getGenID();
}
#ifdef SK_DEBUG
void SkClipStack::Element::dump() const {
static const char* kTypeStrings[] = {
"empty",
"rect",
"rrect",
"path"
};
static_assert(0 == static_cast<int>(DeviceSpaceType::kEmpty), "enum mismatch");
static_assert(1 == static_cast<int>(DeviceSpaceType::kRect), "enum mismatch");
static_assert(2 == static_cast<int>(DeviceSpaceType::kRRect), "enum mismatch");
static_assert(3 == static_cast<int>(DeviceSpaceType::kPath), "enum mismatch");
static_assert(SK_ARRAY_COUNT(kTypeStrings) == kTypeCnt, "enum mismatch");
static const char* kOpStrings[] = {
"difference",
"intersect",
"union",
"xor",
"reverse-difference",
"replace",
};
static_assert(0 == static_cast<int>(kDifference_SkClipOp), "enum mismatch");
static_assert(1 == static_cast<int>(kIntersect_SkClipOp), "enum mismatch");
static_assert(2 == static_cast<int>(kUnion_SkClipOp), "enum mismatch");
static_assert(3 == static_cast<int>(kXOR_SkClipOp), "enum mismatch");
static_assert(4 == static_cast<int>(kReverseDifference_SkClipOp), "enum mismatch");
static_assert(5 == static_cast<int>(kReplace_SkClipOp), "enum mismatch");
static_assert(SK_ARRAY_COUNT(kOpStrings) == SkRegion::kOpCnt, "enum mismatch");
SkDebugf("Type: %s, Op: %s, AA: %s, Save Count: %d\n", kTypeStrings[(int)fDeviceSpaceType],
kOpStrings[static_cast<int>(fOp)], (fDoAA ? "yes" : "no"), fSaveCount);
switch (fDeviceSpaceType) {
case DeviceSpaceType::kEmpty:
SkDebugf("\n");
break;
case DeviceSpaceType::kRect:
this->getDeviceSpaceRect().dump();
SkDebugf("\n");
break;
case DeviceSpaceType::kRRect:
this->getDeviceSpaceRRect().dump();
SkDebugf("\n");
break;
case DeviceSpaceType::kPath:
this->getDeviceSpacePath().dump(nullptr, true, false);
break;
}
}
void SkClipStack::dump() const {
B2TIter iter(*this);
const Element* e;
while ((e = iter.next())) {
e->dump();
SkDebugf("\n");
}
}
#endif