Shrink saveLayer device bounds when it supplies an explicit bounds and has a complex paint
This CL shrinks the bound computed for saveLayers that possess both an explicit
bound and a complex paint (e.g., one that affects transparent black). In this
case the bound of the layer should be the clipped explicit bound rather then
the clip prior/after the saveLayer/restore block.
In the following the first bound is the currently computed bound
while the second is the new/desired one:
For a 100x100 picture
saveLayer (no bound, no paint) [ 0 0 100 100 ] [ 50 50 100 100 ]
setMatrix (translate 50, 50) [ 0 0 100 100 ] [ 50 50 100 100 ]
saveLayer (bound of 0, 0, 50, 50 - complex paint) [ 0 0 100 100 ] [ 50 50 100 100 ]
restore [ 0 0 100 100 ] [ 50 50 100 100 ]
restore [ 0 0 100 100 ] [ 50 50 100 100 ]
Review URL: https://codereview.chromium.org/696763002
diff --git a/src/core/SkPicture.cpp b/src/core/SkPicture.cpp
index 98c28e6..dccb822 100644
--- a/src/core/SkPicture.cpp
+++ b/src/core/SkPicture.cpp
@@ -631,7 +631,7 @@
, fAnalysis(*fRecord) {
// TODO: delay as much of this work until just before first playback?
if (fBBH.get()) {
- SkRecordFillBounds(*fRecord, fBBH.get());
+ SkRecordFillBounds(this->cullRect(), *fRecord, fBBH.get());
}
this->needsNewGenID();
}
diff --git a/src/core/SkRecordDraw.cpp b/src/core/SkRecordDraw.cpp
index ad13270..07c02b6 100644
--- a/src/core/SkRecordDraw.cpp
+++ b/src/core/SkRecordDraw.cpp
@@ -116,14 +116,6 @@
DRAW(DrawData, drawData(r.data, r.length));
#undef DRAW
-
-// This looks silly, I know. Why not just use SkRect::MakeLargest()?
-// In practice, this is well large enough, and it has a few extra advantages:
-// it fits in an SkIRect, and we can munge it a little in both SkRect and
-// SKIRect space without worrying about overflow.
-static const SkRect kUnbounded = { -2e9f, -2e9f, 2e9f, 2e9f };
-
-
// This is an SkRecord visitor that fills an SkBBoxHierarchy.
//
// The interesting part here is how to calculate bounds for ops which don't
@@ -144,11 +136,13 @@
// in for all the control ops we stashed away.
class FillBounds : SkNoncopyable {
public:
- FillBounds(const SkRecord& record, SkBBoxHierarchy* bbh) : fBounds(record.count()) {
+ FillBounds(const SkRect& cullRect, const SkRecord& record, SkBBoxHierarchy* bbh)
+ : fCullRect(cullRect)
+ , fBounds(record.count()) {
// Calculate bounds for all ops. This won't go quite in order, so we'll need
// to store the bounds separately then feed them in to the BBH later in order.
fCTM = &SkMatrix::I();
- fCurrentClipBounds = kUnbounded;
+ fCurrentClipBounds = fCullRect;
for (fCurrentOp = 0; fCurrentOp < record.count(); fCurrentOp++) {
record.visit<void>(fCurrentOp, *this);
}
@@ -161,7 +155,7 @@
// Any control ops not part of any Save/Restore block draw everywhere.
while (!fControlIndices.isEmpty()) {
- this->popControl(kUnbounded);
+ this->popControl(fCullRect);
}
// Finally feed all stored bounds into the BBH. They'll be returned in this order.
@@ -204,7 +198,7 @@
Bounds clip = SkRect::Make(devBounds);
// We don't call adjustAndMap() because as its last step it would intersect the adjusted
// clip bounds with the previous clip, exactly what we can't do when the clip grows.
- fCurrentClipBounds = this->adjustForSaveLayerPaints(&clip) ? clip : kUnbounded;
+ fCurrentClipBounds = this->adjustForSaveLayerPaints(&clip) ? clip : fCullRect;
}
// Restore holds the devBounds for the clip after the {save,saveLayer}/restore block completes.
@@ -216,7 +210,7 @@
const int kSavesToIgnore = 1;
Bounds clip = SkRect::Make(op.devBounds);
fCurrentClipBounds =
- this->adjustForSaveLayerPaints(&clip, kSavesToIgnore) ? clip : kUnbounded;
+ this->adjustForSaveLayerPaints(&clip, kSavesToIgnore) ? clip : fCullRect;
}
// We also take advantage of SaveLayer bounds when present to further cut the clip down.
@@ -253,7 +247,14 @@
void pushSaveBlock(const SkPaint* paint) {
// Starting a new Save block. Push a new entry to represent that.
- SaveBounds sb = { 0, Bounds::MakeEmpty(), paint };
+ SaveBounds sb;
+ sb.controlOps = 0;
+ // If the paint affects transparent black, the bound shouldn't be smaller
+ // than the current clip bounds.
+ sb.bounds =
+ PaintMayAffectTransparentBlack(paint) ? fCurrentClipBounds : Bounds::MakeEmpty();
+ sb.paint = paint;
+
fSaveStack.push(sb);
this->pushControl();
}
@@ -303,19 +304,15 @@
SaveBounds sb;
fSaveStack.pop(&sb);
- // If the paint affects transparent black, we can't trust any of our calculated bounds.
- const Bounds& bounds =
- PaintMayAffectTransparentBlack(sb.paint) ? fCurrentClipBounds : sb.bounds;
-
while (sb.controlOps --> 0) {
- this->popControl(bounds);
+ this->popControl(sb.bounds);
}
// This whole Save block may be part another Save block.
- this->updateSaveBounds(bounds);
+ this->updateSaveBounds(sb.bounds);
// If called from a real Restore (not a phony one for balance), it'll need the bounds.
- return bounds;
+ return sb.bounds;
}
void pushControl() {
@@ -340,7 +337,7 @@
// FIXME: this method could use better bounds
Bounds bounds(const DrawText&) const { return fCurrentClipBounds; }
- Bounds bounds(const Clear&) const { return kUnbounded; } // Ignores the clip.
+ Bounds bounds(const Clear&) const { return fCullRect; } // Ignores the clip.
Bounds bounds(const DrawPaint&) const { return fCurrentClipBounds; }
Bounds bounds(const NoOp&) const { return Bounds::MakeEmpty(); } // NoOps don't draw.
@@ -537,6 +534,9 @@
return rect;
}
+ // We do not guarantee anything for operations outside of the cull rect
+ const SkRect fCullRect;
+
// Conservative identity-space bounds for each op in the SkRecord.
SkAutoTMalloc<Bounds> fBounds;
@@ -554,6 +554,6 @@
} // namespace SkRecords
-void SkRecordFillBounds(const SkRecord& record, SkBBoxHierarchy* bbh) {
- SkRecords::FillBounds(record, bbh);
+void SkRecordFillBounds(const SkRect& cullRect, const SkRecord& record, SkBBoxHierarchy* bbh) {
+ SkRecords::FillBounds(cullRect, record, bbh);
}
diff --git a/src/core/SkRecordDraw.h b/src/core/SkRecordDraw.h
index 75921d1..701e835 100644
--- a/src/core/SkRecordDraw.h
+++ b/src/core/SkRecordDraw.h
@@ -15,7 +15,7 @@
#include "SkRecord.h"
// Fill a BBH to be used by SkRecordDraw to accelerate playback.
-void SkRecordFillBounds(const SkRecord&, SkBBoxHierarchy*);
+void SkRecordFillBounds(const SkRect& cullRect, const SkRecord&, SkBBoxHierarchy*);
// Draw an SkRecord into an SkCanvas. A convenience wrapper around SkRecords::Draw.
void SkRecordDraw(const SkRecord&, SkCanvas*, const SkBBoxHierarchy*, SkDrawPictureCallback*);
diff --git a/tests/RecordDrawTest.cpp b/tests/RecordDrawTest.cpp
index 6105c00..1dcd133 100644
--- a/tests/RecordDrawTest.cpp
+++ b/tests/RecordDrawTest.cpp
@@ -137,7 +137,7 @@
recorder.restore();
TestBBH bbh;
- SkRecordFillBounds(record, &bbh);
+ SkRecordFillBounds(SkRect::MakeWH(SkIntToScalar(W), SkIntToScalar(H)), record, &bbh);
REPORTER_ASSERT(r, bbh.fEntries.count() == 5);
for (int i = 0; i < bbh.fEntries.count(); i++) {
@@ -163,14 +163,14 @@
recorder.drawPosText(text, bytes, pos, SkPaint());
TestBBH bbh;
- SkRecordFillBounds(record, &bbh);
+ SkRecordFillBounds(SkRect::MakeWH(SkIntToScalar(W), SkIntToScalar(H)), record, &bbh);
REPORTER_ASSERT(r, bbh.fEntries.count() == 2);
// We can make these next assertions confidently because SkRecordFillBounds
// builds its bounds by overestimating font metrics in a platform-independent way.
// If that changes, these tests will need to be more flexible.
- REPORTER_ASSERT(r, sloppy_rect_eq(bbh.fEntries[0].bounds, SkRect::MakeLTRB(-110, 0, 140, 60)));
- REPORTER_ASSERT(r, sloppy_rect_eq(bbh.fEntries[1].bounds, SkRect::MakeLTRB(-80, 20, 180, 100)));
+ REPORTER_ASSERT(r, sloppy_rect_eq(bbh.fEntries[0].bounds, SkRect::MakeLTRB(0, 0, 140, 60)));
+ REPORTER_ASSERT(r, sloppy_rect_eq(bbh.fEntries[1].bounds, SkRect::MakeLTRB(0, 20, 180, 100)));
}
// Base test to ensure start/stop range is respected
@@ -251,7 +251,7 @@
// The second bug showed up as adjusting the picture bounds (0,0,50,50) by the drop shadow too.
// The saveLayer, clipRect, and restore bounds were incorrectly (0,0,70,50).
TestBBH bbh;
- SkRecordFillBounds(record, &bbh);
+ SkRecordFillBounds(SkRect::MakeWH(50, 50), record, &bbh);
REPORTER_ASSERT(r, bbh.fEntries.count() == 4);
REPORTER_ASSERT(r, sloppy_rect_eq(bbh.fEntries[0].bounds, SkRect::MakeLTRB(0, 0, 50, 50)));
REPORTER_ASSERT(r, sloppy_rect_eq(bbh.fEntries[1].bounds, SkRect::MakeLTRB(0, 0, 50, 50)));
@@ -259,6 +259,29 @@
REPORTER_ASSERT(r, sloppy_rect_eq(bbh.fEntries[3].bounds, SkRect::MakeLTRB(0, 0, 50, 50)));
}
+// When a saveLayer provides an explicit bound and has a complex paint (e.g., one that
+// affects transparent black), that bound should serve to shrink the area of the required
+// backing store.
+DEF_TEST(RecordDraw_SaveLayerBoundsAffectsClipBounds, r) {
+ SkRecord record;
+ SkRecorder recorder(&record, 50, 50);
+
+ SkPaint p;
+ p.setXfermodeMode(SkXfermode::kSrc_Mode);
+
+ SkRect bounds = SkRect::MakeLTRB(10, 10, 40, 40);
+ recorder.saveLayer(&bounds, &p);
+ recorder.drawRect(SkRect::MakeLTRB(20, 20, 30, 30), SkPaint());
+ recorder.restore();
+
+ TestBBH bbh;
+ SkRecordFillBounds(SkRect::MakeWH(50, 50), record, &bbh);
+ REPORTER_ASSERT(r, bbh.fEntries.count() == 3);
+ REPORTER_ASSERT(r, sloppy_rect_eq(bbh.fEntries[0].bounds, SkRect::MakeLTRB(10, 10, 40, 40)));
+ REPORTER_ASSERT(r, sloppy_rect_eq(bbh.fEntries[1].bounds, SkRect::MakeLTRB(20, 20, 30, 30)));
+ REPORTER_ASSERT(r, sloppy_rect_eq(bbh.fEntries[2].bounds, SkRect::MakeLTRB(10, 10, 40, 40)));
+}
+
DEF_TEST(RecordDraw_drawImage, r){
class SkCanvasMock : public SkCanvas {
public: