SkPaintFilterCanvas skip-draw support
At the time SkPaintFilterCanvas was introduced as a SkDrawFilter replacement,
no clients were relying on the draw veto logic. Now Chromium does.
To facilitate migrating off SkDrawFilter, let's augment SkPaintFilterCanvas
with skip-draw semantics.
A side effect of the CL is that now we call the filter virtual even for null
paints.
BUG=skia:4782
R=reed@google.com,robertphillips@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1577933002
Review URL: https://codereview.chromium.org/1577933002
diff --git a/include/utils/SkPaintFilterCanvas.h b/include/utils/SkPaintFilterCanvas.h
index 0ad7e25..505f965 100644
--- a/include/utils/SkPaintFilterCanvas.h
+++ b/include/utils/SkPaintFilterCanvas.h
@@ -9,10 +9,11 @@
#define SkPaintFilterCanvas_DEFINED
#include "SkNWayCanvas.h"
+#include "SkTLazy.h"
/** \class SkPaintFilterCanvas
- A utility proxy base class for implementing paint filters.
+ A utility proxy base class for implementing draw/paint filters.
*/
class SK_API SkPaintFilterCanvas : public SkNWayCanvas {
public:
@@ -48,13 +49,28 @@
protected:
/**
* Called with the paint that will be used to draw the specified type.
- * The implementation may modify the paint as they wish.
*
- * Note: The base implementation calls onFilterPaint() for top-level/explicit paints only.
+ * Upon return, if filteredPaint is initialized it will replace the original paint
+ * for the current draw. Note that that implementation is responsible for
+ * initializing *filteredPaint (e.g. via set(*paint)).
+ *
+ * The result bool is used to determine whether the draw op is to be
+ * executed (true) or skipped (false). When the draw is skipped, filteredPaint is
+ * ignored.
+ *
+ * Note: The base implementation calls onFilter() for top-level/explicit paints only.
* To also filter encapsulated paints (e.g. SkPicture, SkTextBlob), clients may need to
* override the relevant methods (i.e. drawPicture, drawTextBlob).
*/
- virtual void onFilterPaint(SkPaint* paint, Type type) const = 0;
+ virtual bool onFilter(const SkPaint* paint, Type type, SkTLazy<SkPaint>* filteredPaint) const {
+ if (paint) {
+ this->onFilterPaint(filteredPaint->set(*paint), type);
+ }
+ return true;
+ }
+
+ // DEPRECATED - do not use
+ virtual void onFilterPaint(SkPaint*, Type) const { }
void onDrawPaint(const SkPaint&) override;
void onDrawPoints(PointMode, size_t count, const SkPoint pts[], const SkPaint&) override;
@@ -66,11 +82,13 @@
void onDrawBitmap(const SkBitmap&, SkScalar left, SkScalar top, const SkPaint*) override;
void onDrawBitmapRect(const SkBitmap&, const SkRect* src, const SkRect& dst, const SkPaint*,
SrcRectConstraint) override;
+ void onDrawBitmapNine(const SkBitmap&, const SkIRect& center, const SkRect& dst,
+ const SkPaint*) override;
void onDrawImage(const SkImage*, SkScalar left, SkScalar top, const SkPaint*) override;
void onDrawImageRect(const SkImage*, const SkRect* src, const SkRect& dst,
const SkPaint*, SrcRectConstraint) override;
- void onDrawBitmapNine(const SkBitmap&, const SkIRect& center, const SkRect& dst,
- const SkPaint*) override;
+ void onDrawImageNine(const SkImage*, const SkIRect& center, const SkRect& dst,
+ const SkPaint*) override;
void onDrawVertices(VertexMode vmode, int vertexCount,
const SkPoint vertices[], const SkPoint texs[],
const SkColor colors[], SkXfermode* xmode,
diff --git a/samplecode/SampleApp.cpp b/samplecode/SampleApp.cpp
index 9f0bd45..ce2cfb2 100644
--- a/samplecode/SampleApp.cpp
+++ b/samplecode/SampleApp.cpp
@@ -465,34 +465,39 @@
public:
FlagsFilterCanvas(SkCanvas* canvas, SkOSMenu::TriState lcd, SkOSMenu::TriState aa,
SkOSMenu::TriState subpixel, int hinting, int filterQuality)
- : INHERITED(canvas->imageInfo().width(), canvas->imageInfo().height())
+ : INHERITED(canvas)
, fLCDState(lcd)
, fAAState(aa)
, fSubpixelState(subpixel)
, fHintingState(hinting)
, fFilterQualityIndex(filterQuality) {
SkASSERT((unsigned)filterQuality < SK_ARRAY_COUNT(gFilterQualityStates));
-
- this->addCanvas(canvas);
}
protected:
- void onFilterPaint(SkPaint* paint, Type t) const override {
+ bool onFilter(const SkPaint* paint, Type t, SkTLazy<SkPaint>* filteredPaint) const override {
+ if (!paint) {
+ return true;
+ }
+
+ filteredPaint->set(*paint);
if (kText_Type == t && SkOSMenu::kMixedState != fLCDState) {
- paint->setLCDRenderText(SkOSMenu::kOnState == fLCDState);
+ filteredPaint->get()->setLCDRenderText(SkOSMenu::kOnState == fLCDState);
}
if (SkOSMenu::kMixedState != fAAState) {
- paint->setAntiAlias(SkOSMenu::kOnState == fAAState);
+ filteredPaint->get()->setAntiAlias(SkOSMenu::kOnState == fAAState);
}
if (0 != fFilterQualityIndex) {
- paint->setFilterQuality(gFilterQualityStates[fFilterQualityIndex].fQuality);
+ filteredPaint->get()->setFilterQuality(
+ gFilterQualityStates[fFilterQualityIndex].fQuality);
}
if (SkOSMenu::kMixedState != fSubpixelState) {
- paint->setSubpixelText(SkOSMenu::kOnState == fSubpixelState);
+ filteredPaint->get()->setSubpixelText(SkOSMenu::kOnState == fSubpixelState);
}
if (0 != fHintingState && fHintingState < (int)SK_ARRAY_COUNT(gHintingStates)) {
- paint->setHinting(gHintingStates[fHintingState].hinting);
+ filteredPaint->get()->setHinting(gHintingStates[fHintingState].hinting);
}
+ return true;
}
private:
diff --git a/src/utils/SkPaintFilterCanvas.cpp b/src/utils/SkPaintFilterCanvas.cpp
index ce1e4b7..0a5b7e6 100644
--- a/src/utils/SkPaintFilterCanvas.cpp
+++ b/src/utils/SkPaintFilterCanvas.cpp
@@ -12,20 +12,24 @@
class SkPaintFilterCanvas::AutoPaintFilter {
public:
- AutoPaintFilter(const SkPaintFilterCanvas* canvas, Type type, const SkPaint* paint) {
- if (paint) {
- canvas->onFilterPaint(fLazyPaint.set(*paint), type);
- }
+ AutoPaintFilter(const SkPaintFilterCanvas* canvas, Type type, const SkPaint* paint)
+ : fOrigPaint(paint) {
+ fShouldDraw = canvas->onFilter(fOrigPaint, type, &fFilteredPaint);
}
- AutoPaintFilter(const SkPaintFilterCanvas* canvas, Type type, const SkPaint& paint) {
- canvas->onFilterPaint(fLazyPaint.set(paint), type);
+ AutoPaintFilter(const SkPaintFilterCanvas* canvas, Type type, const SkPaint& paint)
+ : AutoPaintFilter(canvas, type, &paint) { }
+
+ const SkPaint* paint() const {
+ return fFilteredPaint.isValid() ? fFilteredPaint.get() : fOrigPaint;
}
- const SkPaint* paint() const { return fLazyPaint.getMaybeNull(); }
+ bool shouldDraw() const { return fShouldDraw; }
private:
- SkTLazy<SkPaint> fLazyPaint;
+ const SkPaint* fOrigPaint;
+ SkTLazy<SkPaint> fFilteredPaint;
+ bool fShouldDraw;
};
SkPaintFilterCanvas::SkPaintFilterCanvas(int width, int height) : INHERITED(width, height) { }
@@ -44,70 +48,102 @@
void SkPaintFilterCanvas::onDrawPaint(const SkPaint& paint) {
AutoPaintFilter apf(this, kPaint_Type, paint);
- this->INHERITED::onDrawPaint(*apf.paint());
+ if (apf.shouldDraw()) {
+ this->INHERITED::onDrawPaint(*apf.paint());
+ }
}
void SkPaintFilterCanvas::onDrawPoints(PointMode mode, size_t count, const SkPoint pts[],
const SkPaint& paint) {
AutoPaintFilter apf(this, kPoint_Type, paint);
- this->INHERITED::onDrawPoints(mode, count, pts, *apf.paint());
+ if (apf.shouldDraw()) {
+ this->INHERITED::onDrawPoints(mode, count, pts, *apf.paint());
+ }
}
void SkPaintFilterCanvas::onDrawRect(const SkRect& rect, const SkPaint& paint) {
AutoPaintFilter apf(this, kRect_Type, paint);
- this->INHERITED::onDrawRect(rect, *apf.paint());
+ if (apf.shouldDraw()) {
+ this->INHERITED::onDrawRect(rect, *apf.paint());
+ }
}
void SkPaintFilterCanvas::onDrawRRect(const SkRRect& rrect, const SkPaint& paint) {
AutoPaintFilter apf(this, kRRect_Type, paint);
- this->INHERITED::onDrawRRect(rrect, *apf.paint());
+ if (apf.shouldDraw()) {
+ this->INHERITED::onDrawRRect(rrect, *apf.paint());
+ }
}
void SkPaintFilterCanvas::onDrawDRRect(const SkRRect& outer, const SkRRect& inner,
const SkPaint& paint) {
AutoPaintFilter apf(this, kDRRect_Type, paint);
- this->INHERITED::onDrawDRRect(outer, inner, *apf.paint());
+ if (apf.shouldDraw()) {
+ this->INHERITED::onDrawDRRect(outer, inner, *apf.paint());
+ }
}
void SkPaintFilterCanvas::onDrawOval(const SkRect& rect, const SkPaint& paint) {
AutoPaintFilter apf(this, kOval_Type, paint);
- this->INHERITED::onDrawOval(rect, *apf.paint());
+ if (apf.shouldDraw()) {
+ this->INHERITED::onDrawOval(rect, *apf.paint());
+ }
}
void SkPaintFilterCanvas::onDrawPath(const SkPath& path, const SkPaint& paint) {
AutoPaintFilter apf(this, kPath_Type, paint);
- this->INHERITED::onDrawPath(path, *apf.paint());
+ if (apf.shouldDraw()) {
+ this->INHERITED::onDrawPath(path, *apf.paint());
+ }
}
void SkPaintFilterCanvas::onDrawBitmap(const SkBitmap& bm, SkScalar left, SkScalar top,
const SkPaint* paint) {
AutoPaintFilter apf(this, kBitmap_Type, paint);
- this->INHERITED::onDrawBitmap(bm, left, top, apf.paint());
+ if (apf.shouldDraw()) {
+ this->INHERITED::onDrawBitmap(bm, left, top, apf.paint());
+ }
}
void SkPaintFilterCanvas::onDrawBitmapRect(const SkBitmap& bm, const SkRect* src, const SkRect& dst,
const SkPaint* paint, SrcRectConstraint constraint) {
AutoPaintFilter apf(this, kBitmap_Type, paint);
- this->INHERITED::onDrawBitmapRect(bm, src, dst, apf.paint(), constraint);
+ if (apf.shouldDraw()) {
+ this->INHERITED::onDrawBitmapRect(bm, src, dst, apf.paint(), constraint);
+ }
+}
+
+void SkPaintFilterCanvas::onDrawBitmapNine(const SkBitmap& bm, const SkIRect& center,
+ const SkRect& dst, const SkPaint* paint) {
+ AutoPaintFilter apf(this, kBitmap_Type, paint);
+ if (apf.shouldDraw()) {
+ this->INHERITED::onDrawBitmapNine(bm, center, dst, apf.paint());
+ }
}
void SkPaintFilterCanvas::onDrawImage(const SkImage* image, SkScalar left, SkScalar top,
const SkPaint* paint) {
AutoPaintFilter apf(this, kBitmap_Type, paint);
- this->INHERITED::onDrawImage(image, left, top, apf.paint());
+ if (apf.shouldDraw()) {
+ this->INHERITED::onDrawImage(image, left, top, apf.paint());
+ }
}
void SkPaintFilterCanvas::onDrawImageRect(const SkImage* image, const SkRect* src,
const SkRect& dst, const SkPaint* paint,
SrcRectConstraint constraint) {
AutoPaintFilter apf(this, kBitmap_Type, paint);
- this->INHERITED::onDrawImageRect(image, src, dst, apf.paint(), constraint);
+ if (apf.shouldDraw()) {
+ this->INHERITED::onDrawImageRect(image, src, dst, apf.paint(), constraint);
+ }
}
-void SkPaintFilterCanvas::onDrawBitmapNine(const SkBitmap& bm, const SkIRect& center,
- const SkRect& dst, const SkPaint* paint) {
+void SkPaintFilterCanvas::onDrawImageNine(const SkImage* image, const SkIRect& center,
+ const SkRect& dst, const SkPaint* paint) {
AutoPaintFilter apf(this, kBitmap_Type, paint);
- this->INHERITED::onDrawBitmapNine(bm, center, dst, apf.paint());
+ if (apf.shouldDraw()) {
+ this->INHERITED::onDrawImageNine(image, center, dst, apf.paint());
+ }
}
void SkPaintFilterCanvas::onDrawVertices(VertexMode vmode, int vertexCount,
@@ -116,49 +152,65 @@
const uint16_t indices[], int indexCount,
const SkPaint& paint) {
AutoPaintFilter apf(this, kVertices_Type, paint);
- this->INHERITED::onDrawVertices(vmode, vertexCount, vertices, texs, colors, xmode, indices,
- indexCount, *apf.paint());
+ if (apf.shouldDraw()) {
+ this->INHERITED::onDrawVertices(vmode, vertexCount, vertices, texs, colors, xmode, indices,
+ indexCount, *apf.paint());
+ }
}
void SkPaintFilterCanvas::onDrawPatch(const SkPoint cubics[], const SkColor colors[],
const SkPoint texCoords[], SkXfermode* xmode,
const SkPaint& paint) {
AutoPaintFilter apf(this, kPatch_Type, paint);
- this->INHERITED::onDrawPatch(cubics, colors, texCoords, xmode, *apf.paint());
+ if (apf.shouldDraw()) {
+ this->INHERITED::onDrawPatch(cubics, colors, texCoords, xmode, *apf.paint());
+ }
}
void SkPaintFilterCanvas::onDrawPicture(const SkPicture* picture, const SkMatrix* m,
const SkPaint* paint) {
AutoPaintFilter apf(this, kPicture_Type, paint);
- this->INHERITED::onDrawPicture(picture, m, apf.paint());
+ if (apf.shouldDraw()) {
+ this->INHERITED::onDrawPicture(picture, m, apf.paint());
+ }
}
void SkPaintFilterCanvas::onDrawText(const void* text, size_t byteLength, SkScalar x, SkScalar y,
const SkPaint& paint) {
AutoPaintFilter apf(this, kText_Type, paint);
- this->INHERITED::onDrawText(text, byteLength, x, y, *apf.paint());
+ if (apf.shouldDraw()) {
+ this->INHERITED::onDrawText(text, byteLength, x, y, *apf.paint());
+ }
}
void SkPaintFilterCanvas::onDrawPosText(const void* text, size_t byteLength, const SkPoint pos[],
const SkPaint& paint) {
AutoPaintFilter apf(this, kText_Type, paint);
- this->INHERITED::onDrawPosText(text, byteLength, pos, *apf.paint());
+ if (apf.shouldDraw()) {
+ this->INHERITED::onDrawPosText(text, byteLength, pos, *apf.paint());
+ }
}
void SkPaintFilterCanvas::onDrawPosTextH(const void* text, size_t byteLength, const SkScalar xpos[],
SkScalar constY, const SkPaint& paint) {
AutoPaintFilter apf(this, kText_Type, paint);
- this->INHERITED::onDrawPosTextH(text, byteLength, xpos, constY, *apf.paint());
+ if (apf.shouldDraw()) {
+ this->INHERITED::onDrawPosTextH(text, byteLength, xpos, constY, *apf.paint());
+ }
}
void SkPaintFilterCanvas::onDrawTextOnPath(const void* text, size_t byteLength, const SkPath& path,
const SkMatrix* matrix, const SkPaint& paint) {
AutoPaintFilter apf(this, kText_Type, paint);
- this->INHERITED::onDrawTextOnPath(text, byteLength, path, matrix, *apf.paint());
+ if (apf.shouldDraw()) {
+ this->INHERITED::onDrawTextOnPath(text, byteLength, path, matrix, *apf.paint());
+ }
}
void SkPaintFilterCanvas::onDrawTextBlob(const SkTextBlob* blob, SkScalar x, SkScalar y,
const SkPaint& paint) {
AutoPaintFilter apf(this, kTextBlob_Type, paint);
- this->INHERITED::onDrawTextBlob(blob, x, y, *apf.paint());
+ if (apf.shouldDraw()) {
+ this->INHERITED::onDrawTextBlob(blob, x, y, *apf.paint());
+ }
}
diff --git a/src/utils/debugger/SkDebugCanvas.cpp b/src/utils/debugger/SkDebugCanvas.cpp
index 560976c..9f11a9e 100644
--- a/src/utils/debugger/SkDebugCanvas.cpp
+++ b/src/utils/debugger/SkDebugCanvas.cpp
@@ -69,15 +69,19 @@
, fFilterQuality(quality) {}
protected:
- void onFilterPaint(SkPaint* paint, Type) const override {
- if (nullptr != fOverdrawXfermode.get()) {
- paint->setAntiAlias(false);
- paint->setXfermode(fOverdrawXfermode.get());
- }
+ bool onFilter(const SkPaint* paint, Type, SkTLazy<SkPaint>* filteredPaint) const override {
+ if (paint) {
+ filteredPaint->set(*paint);
+ if (nullptr != fOverdrawXfermode.get()) {
+ filteredPaint->get()->setAntiAlias(false);
+ filteredPaint->get()->setXfermode(fOverdrawXfermode.get());
+ }
- if (fOverrideFilterQuality) {
- paint->setFilterQuality(fFilterQuality);
+ if (fOverrideFilterQuality) {
+ filteredPaint->get()->setFilterQuality(fFilterQuality);
+ }
}
+ return true;
}
void onDrawPicture(const SkPicture* picture,
diff --git a/tests/CanvasTest.cpp b/tests/CanvasTest.cpp
index 87705dc..516dd05 100644
--- a/tests/CanvasTest.cpp
+++ b/tests/CanvasTest.cpp
@@ -730,7 +730,7 @@
MockFilterCanvas(SkCanvas* canvas) : INHERITED(canvas) { }
protected:
- void onFilterPaint(SkPaint *paint, Type type) const override { }
+ bool onFilter(const SkPaint*, Type, SkTLazy<SkPaint>*) const override { return true; }
private:
typedef SkPaintFilterCanvas INHERITED;