Moving updateClipConservativelyUsingBounds into SkCanvas
This method is being moved from SkPictureRecord to become a protected member of SkCanvas so that other classes derived from SkCanvas can use it.
This Patch also applies the fix provided by updateClipConservativelyUsingBounds to SkPictureUtils::GatherPixelRefs
BUG=https://code.google.com/p/chromium/issues/detail?id=244893
Review URL: https://codereview.chromium.org/15894005
git-svn-id: http://skia.googlecode.com/svn/trunk@9326 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/include/core/SkCanvas.h b/include/core/SkCanvas.h
index 821f86b..b315797 100644
--- a/include/core/SkCanvas.h
+++ b/include/core/SkCanvas.h
@@ -1011,6 +1011,11 @@
bool clipRectBounds(const SkRect* bounds, SaveFlags flags,
SkIRect* intersection);
+ // Called by child classes that override clipPath and clipRRect to only
+ // track fast conservative clip bounds, rather than exact clips.
+ bool updateClipConservativelyUsingBounds(const SkRect&, SkRegion::Op,
+ bool inverseFilled);
+
// notify our surface (if we have one) that we are about to draw, so it
// can perform copy-on-write or invalidate any cached images
void predrawNotify();
diff --git a/src/core/SkCanvas.cpp b/src/core/SkCanvas.cpp
index e26007f..d8fd0a4 100644
--- a/src/core/SkCanvas.cpp
+++ b/src/core/SkCanvas.cpp
@@ -1279,6 +1279,80 @@
return clipPathHelper(this, fMCRec->fRasterClip, devPath, op, doAA);
}
+bool SkCanvas::updateClipConservativelyUsingBounds(const SkRect& bounds, SkRegion::Op op,
+ bool inverseFilled) {
+ // This is for updating the clip conservatively using only bounds
+ // information.
+ // Contract:
+ // The current clip must contain the true clip. The true
+ // clip is the clip that would have normally been computed
+ // by calls to clipPath and clipRRect
+ // Objective:
+ // Keep the current clip as small as possible without
+ // breaking the contract, using only clip bounding rectangles
+ // (for performance).
+
+ // N.B.: This *never* calls back through a virtual on canvas, so subclasses
+ // don't have to worry about getting caught in a loop. Thus anywhere
+ // we call a virtual method, we explicitly prefix it with
+ // SkCanvas:: to be sure to call the base-class.
+
+ if (inverseFilled) {
+ switch (op) {
+ case SkRegion::kIntersect_Op:
+ case SkRegion::kDifference_Op:
+ // These ops can only shrink the current clip. So leaving
+ // the clip unchanges conservatively respects the contract.
+ return this->getClipDeviceBounds(NULL);
+ case SkRegion::kUnion_Op:
+ case SkRegion::kReplace_Op:
+ case SkRegion::kReverseDifference_Op:
+ case SkRegion::kXOR_Op:
+ {
+ // These ops can grow the current clip up to the extents of
+ // the input clip, which is inverse filled, so we just set
+ // the current clip to the device bounds.
+ SkRect deviceBounds;
+ SkIRect deviceIBounds;
+ this->getDevice()->getGlobalBounds(&deviceIBounds);
+ deviceBounds = SkRect::MakeFromIRect(deviceIBounds);
+ this->SkCanvas::save(SkCanvas::kMatrix_SaveFlag);
+ // set the clip in device space
+ this->SkCanvas::setMatrix(SkMatrix::I());
+ bool result = this->SkCanvas::clipRect(deviceBounds,
+ SkRegion::kReplace_Op, false);
+ this->SkCanvas::restore(); //pop the matrix, but keep the clip
+ return result;
+ }
+ default:
+ SkASSERT(0); // unhandled op?
+ }
+ } else {
+ // Not inverse filled
+ switch (op) {
+ case SkRegion::kIntersect_Op:
+ case SkRegion::kUnion_Op:
+ case SkRegion::kReplace_Op:
+ return this->SkCanvas::clipRect(bounds, op, false);
+ case SkRegion::kDifference_Op:
+ // Difference can only shrink the current clip.
+ // Leaving clip unchanged conservatively fullfills the contract.
+ return this->getClipDeviceBounds(NULL);
+ case SkRegion::kReverseDifference_Op:
+ // To reverse, we swap in the bounds with a replace op.
+ // As with difference, leave it unchanged.
+ return this->SkCanvas::clipRect(bounds, SkRegion::kReplace_Op, false);
+ case SkRegion::kXOR_Op:
+ // Be conservative, based on (A XOR B) always included in (A union B),
+ // which is always included in (bounds(A) union bounds(B))
+ return this->SkCanvas::clipRect(bounds, SkRegion::kUnion_Op, false);
+ default:
+ SkASSERT(0); // unhandled op?
+ }
+ }
+ return true;
+}
+
bool SkCanvas::clipRegion(const SkRegion& rgn, SkRegion::Op op) {
AutoValidateClip avc(this);
diff --git a/src/core/SkPictureRecord.cpp b/src/core/SkPictureRecord.cpp
index fc85028..9157363 100644
--- a/src/core/SkPictureRecord.cpp
+++ b/src/core/SkPictureRecord.cpp
@@ -759,7 +759,7 @@
validate(initialOffset, size);
if (fRecordFlags & SkPicture::kUsePathBoundsForClip_RecordingFlag) {
- return this->updateClipConservativelyUsingBounds(rrect.getBounds(), op, doAA, false);
+ return this->updateClipConservativelyUsingBounds(rrect.getBounds(), op, false);
} else {
return this->INHERITED::clipRRect(rrect, op, doAA);
}
@@ -787,83 +787,13 @@
validate(initialOffset, size);
if (fRecordFlags & SkPicture::kUsePathBoundsForClip_RecordingFlag) {
- return this->updateClipConservativelyUsingBounds(path.getBounds(), op, doAA,
+ return this->updateClipConservativelyUsingBounds(path.getBounds(), op,
path.isInverseFillType());
} else {
return this->INHERITED::clipPath(path, op, doAA);
}
}
-bool SkPictureRecord::updateClipConservativelyUsingBounds(const SkRect& bounds, SkRegion::Op op,
- bool doAA, bool inverseFilled) {
- // This is for updating the clip when kUsePathBoundsForClip_RecordingFlag
- // is set. The current clip of the recording canvas is used for quick
- // culling of clipped-out primitives, which must not yield any false
- // positives, while still rejecting as many as possible.
- // Contract:
- // The current clip must contain the true clip. The true
- // clip is the clip that would have been computed with
- // kUsePathBoundsForClip_RecordingFlag disabled.
- // Objective:
- // Keep the current clip as small as possible without
- // breaking the contract, using only clip bounding rectangles
- // (for performance).
- if (inverseFilled) {
- switch (op) {
- case SkRegion::kIntersect_Op:
- case SkRegion::kDifference_Op:
- // These ops can only shrink the current clip. So leaving
- // the clip unchanges conservatively respects the contract.
- return this->getClipDeviceBounds(NULL);
- case SkRegion::kUnion_Op:
- case SkRegion::kReplace_Op:
- case SkRegion::kReverseDifference_Op:
- case SkRegion::kXOR_Op:
- {
- // These ops can grow the current clip up to the extents of
- // the input clip, which is inverse filled, so we just set
- // the current clip to the device bounds.
- SkRect deviceBounds;
- SkIRect deviceIBounds;
- this->getDevice()->getGlobalBounds(&deviceIBounds);
- deviceBounds = SkRect::MakeFromIRect(deviceIBounds);
- this->INHERITED::save(SkCanvas::kMatrix_SaveFlag);
- // set the clip in device space
- this->INHERITED::setMatrix(SkMatrix::I());
- bool result = this->INHERITED::clipRect(deviceBounds,
- SkRegion::kReplace_Op, doAA);
- this->INHERITED::restore(); //pop the matrix, but keep the clip
- return result;
- }
- default:
- SkASSERT(0); // unhandled op?
- }
- } else {
- // Not inverse filled
- switch (op) {
- case SkRegion::kIntersect_Op:
- case SkRegion::kUnion_Op:
- case SkRegion::kReplace_Op:
- return this->INHERITED::clipRect(bounds, op, doAA);
- case SkRegion::kDifference_Op:
- // Difference can only shrink the current clip.
- // Leaving clip unchanged conservatively fullfills the contract.
- return this->getClipDeviceBounds(NULL);
- case SkRegion::kReverseDifference_Op:
- // To reverse, we swap in the bounds with a replace op.
- // As with difference, leave it unchanged.
- return this->INHERITED::clipRect(bounds, SkRegion::kReplace_Op, doAA);
- case SkRegion::kXOR_Op:
- // Be conservative, based on (A XOR B) always included in (A union B),
- // which is always included in (bounds(A) union bounds(B))
- return this->INHERITED::clipRect(bounds, SkRegion::kUnion_Op, doAA);
- default:
- SkASSERT(0); // unhandled op?
- }
- }
- return true;
-}
-
bool SkPictureRecord::clipRegion(const SkRegion& region, SkRegion::Op op) {
// op + region index + clip params
uint32_t size = 3 * kUInt32Size;
diff --git a/src/core/SkPictureRecord.h b/src/core/SkPictureRecord.h
index 95ce5d2..0ea857d 100644
--- a/src/core/SkPictureRecord.h
+++ b/src/core/SkPictureRecord.h
@@ -106,8 +106,6 @@
void endRecording();
private:
- bool updateClipConservativelyUsingBounds(const SkRect&, SkRegion::Op,
- bool doAA, bool inverseFilled);
void handleOptimization(int opt);
void recordRestoreOffsetPlaceholder(SkRegion::Op);
void fillRestoreOffsetPlaceholdersForCurrentStackLevel(
diff --git a/src/utils/SkPictureUtils.cpp b/src/utils/SkPictureUtils.cpp
index de4b440..5ef9e48 100644
--- a/src/utils/SkPictureUtils.cpp
+++ b/src/utils/SkPictureUtils.cpp
@@ -180,11 +180,11 @@
// false positives and negatives.
virtual bool clipPath(const SkPath& path, SkRegion::Op op,
bool doAA) SK_OVERRIDE {
- return this->INHERITED::clipRect(path.getBounds(), op, false);
+ return this->updateClipConservativelyUsingBounds(path.getBounds(), op, path.isInverseFillType());
}
virtual bool clipRRect(const SkRRect& rrect, SkRegion::Op op,
bool doAA) SK_OVERRIDE {
- return this->INHERITED::clipRect(rrect.getBounds(), op, false);
+ return this->updateClipConservativelyUsingBounds(rrect.getBounds(), op, false);
}
private: