add backdrop option to SaveLayerRec

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1523053003

Review URL: https://codereview.chromium.org/1523053003

6 files changed, 78 insertions, 23 deletions

diff --git a/src/core/SkCanvas.cpp b/src/core/SkCanvas.cpp
index e5ca9ce6c1..bc354ab3c3 100644
--- a/src/core/SkCanvas.cpp
+++ b/src/core/SkCanvas.cpp
@@ -114,7 +114,6 @@ bool SkCanvas::Internal_Private_GetTreatSpriteAsBitmap() {
 
 // experimental for faster tiled drawing...
 //#define SK_ENABLE_CLIP_QUICKREJECT
-
 //#define SK_TRACE_SAVERESTORE
 
 #ifdef SK_TRACE_SAVERESTORE
@@ -481,7 +480,7 @@ public:
                 // Make rawBounds include all paint outsets except for those due to image filters.
                 rawBounds = &apply_paint_to_bounds_sans_imagefilter(*fPaint, *rawBounds, &storage);
             }
-            (void)canvas->internalSaveLayer(SkCanvas::SaveLayerRec(rawBounds, &tmp, 0),
+            (void)canvas->internalSaveLayer(SkCanvas::SaveLayerRec(rawBounds, &tmp),
                                             SkCanvas::kFullLayer_SaveLayerStrategy);
             fTempLayerForImageFilter = true;
             // we remove the imagefilter/xfermode inside doNext()
@@ -1173,7 +1172,8 @@ int SkCanvas::saveLayer(const SaveLayerRec& origRec) {
     return this->getSaveCount() - 1;
 }
 
-static void draw_filter_into_device(SkBaseDevice* src, SkImageFilter* filter, SkBaseDevice* dst) {
+static void draw_filter_into_device(SkBaseDevice* src, const SkImageFilter* filter,
+                                    SkBaseDevice* dst, const SkMatrix& ctm) {
 
     SkBitmap srcBM;
 
@@ -1198,9 +1198,12 @@ static void draw_filter_into_device(SkBaseDevice* src, SkImageFilter* filter, Sk
 
     SkCanvas c(dst);
 
+    SkAutoTUnref<SkImageFilter> localF(filter->newWithLocalMatrix(ctm));
     SkPaint p;
-    p.setImageFilter(filter);
-    c.drawBitmap(srcBM, 0, 0, &p);
+    p.setImageFilter(localF);
+    const SkScalar x = SkIntToScalar(src->getOrigin().x());
+    const SkScalar y = SkIntToScalar(src->getOrigin().y());
+    c.drawBitmap(srcBM, x, y, &p);
 }
 
 void SkCanvas::internalSaveLayer(const SaveLayerRec& rec, SaveLayerStrategy strategy) {
@@ -1268,11 +1271,10 @@ void SkCanvas::internalSaveLayer(const SaveLayerRec& rec, SaveLayerStrategy stra
         }
         device = newDev;
     }
-
     device->setOrigin(ir.fLeft, ir.fTop);
 
-    if (0) {
-        draw_filter_into_device(fMCRec->fTopLayer->fDevice, nullptr, device);
+    if (rec.fBackdrop) {
+        draw_filter_into_device(fMCRec->fTopLayer->fDevice, rec.fBackdrop, device, fMCRec->fMatrix);
     }
 
     DeviceCM* layer =
diff --git a/src/core/SkPictureFlat.h b/src/core/SkPictureFlat.h
index cbacc8e664..4eee04fcda 100644
--- a/src/core/SkPictureFlat.h
+++ b/src/core/SkPictureFlat.h
@@ -75,9 +75,10 @@ enum DrawType {
     DRAW_IMAGE_NINE,
     DRAW_IMAGE_RECT,
 
-    SAVE_LAYER_SAVELAYERFLAGS,
+    SAVE_LAYER_SAVELAYERFLAGS_DEPRECATED_JAN_2016,
+    SAVE_LAYER_SAVELAYERREC,
 
-    LAST_DRAWTYPE_ENUM = SAVE_LAYER_SAVELAYERFLAGS,
+    LAST_DRAWTYPE_ENUM = SAVE_LAYER_SAVELAYERREC,
 };
 
 // In the 'match' method, this constant will match any flavor of DRAW_BITMAP*
@@ -95,6 +96,13 @@ enum DrawAtlasFlags {
     DRAW_ATLAS_HAS_CULL     = 1 << 1,
 };
 
+enum SaveLayerRecFlatFlags {
+    SAVELAYERREC_HAS_BOUNDS     = 1 << 0,
+    SAVELAYERREC_HAS_PAINT      = 1 << 1,
+    SAVELAYERREC_HAS_BACKDROP   = 1 << 2,
+    SAVELAYERREC_HAS_FLAGS      = 1 << 3,
+};
+
 ///////////////////////////////////////////////////////////////////////////////
 // clipparams are packed in 5 bits
 //  doAA:1 | regionOp:4
diff --git a/src/core/SkPicturePlayback.cpp b/src/core/SkPicturePlayback.cpp
index 82b8f0e578..4b028f714e 100644
--- a/src/core/SkPicturePlayback.cpp
+++ b/src/core/SkPicturePlayback.cpp
@@ -483,11 +483,29 @@ void SkPicturePlayback::handleOp(SkReader32* reader,
             auto flags = SkCanvas::LegacySaveFlagsToSaveLayerFlags(reader->readInt());
             canvas->saveLayer(SkCanvas::SaveLayerRec(boundsPtr, paint, flags));
         } break;
-        case SAVE_LAYER_SAVELAYERFLAGS: {
+        case SAVE_LAYER_SAVELAYERFLAGS_DEPRECATED_JAN_2016: {
             const SkRect* boundsPtr = get_rect_ptr(reader);
             const SkPaint* paint = fPictureData->getPaint(reader);
             canvas->saveLayer(SkCanvas::SaveLayerRec(boundsPtr, paint, reader->readInt()));
         } break;
+        case SAVE_LAYER_SAVELAYERREC: {
+            SkCanvas::SaveLayerRec rec(nullptr, nullptr, nullptr, 0);
+            const uint32_t flatFlags = reader->readInt();
+            if (flatFlags & SAVELAYERREC_HAS_BOUNDS) {
+                rec.fBounds = &reader->skipT<SkRect>();
+            }
+            if (flatFlags & SAVELAYERREC_HAS_PAINT) {
+                rec.fPaint = fPictureData->getPaint(reader);
+            }
+            if (flatFlags & SAVELAYERREC_HAS_BACKDROP) {
+                const SkPaint* paint = fPictureData->getPaint(reader);
+                rec.fBackdrop = paint->getImageFilter();
+            }
+            if (flatFlags & SAVELAYERREC_HAS_FLAGS) {
+                rec.fSaveLayerFlags = reader->readInt();
+            }
+            canvas->saveLayer(rec);
+        } break;
         case SCALE: {
             SkScalar sx = reader->readScalar();
             SkScalar sy = reader->readScalar();
diff --git a/src/core/SkPictureRecord.cpp b/src/core/SkPictureRecord.cpp
index 7907ee0d29..2822a1ac16 100644
--- a/src/core/SkPictureRecord.cpp
+++ b/src/core/SkPictureRecord.cpp
@@ -76,19 +76,44 @@ SkCanvas::SaveLayerStrategy SkPictureRecord::getSaveLayerStrategy(const SaveLaye
 void SkPictureRecord::recordSaveLayer(const SaveLayerRec& rec) {
     fContentInfo.onSaveLayer();
 
-    // op + bool for 'bounds'
+    // op + flatflags
     size_t size = 2 * kUInt32Size;
+    uint32_t flatFlags = 0;
+
     if (rec.fBounds) {
-        size += sizeof(*rec.fBounds); // + rect
+        flatFlags |= SAVELAYERREC_HAS_BOUNDS;
+        size += sizeof(*rec.fBounds);
+    }
+    if (rec.fPaint) {
+        flatFlags |= SAVELAYERREC_HAS_PAINT;
+        size += sizeof(uint32_t); // index
+    }
+    if (rec.fBackdrop) {
+        flatFlags |= SAVELAYERREC_HAS_BACKDROP;
+        size += sizeof(uint32_t); // (paint) index
+    }
+    if (rec.fSaveLayerFlags) {
+        flatFlags |= SAVELAYERREC_HAS_FLAGS;
+        size += sizeof(uint32_t);
     }
-    // + paint index + flags
-    size += 2 * kUInt32Size;
-
-    size_t initialOffset = this->addDraw(SAVE_LAYER_SAVELAYERFLAGS, &size);
-    this->addRectPtr(rec.fBounds);
-    this->addPaintPtr(rec.fPaint);
-    this->addInt(rec.fSaveLayerFlags);
 
+    const size_t initialOffset = this->addDraw(SAVE_LAYER_SAVELAYERREC, &size);
+    this->addInt(flatFlags);
+    if (flatFlags & SAVELAYERREC_HAS_BOUNDS) {
+        this->addRect(*rec.fBounds);
+    }
+    if (flatFlags & SAVELAYERREC_HAS_PAINT) {
+        this->addPaintPtr(rec.fPaint);
+    }
+    if (flatFlags & SAVELAYERREC_HAS_BACKDROP) {
+        // overkill, but we didn't already track single flattenables, so using a paint for that
+        SkPaint paint;
+        paint.setImageFilter(const_cast<SkImageFilter*>(rec.fBackdrop));
+        this->addPaint(paint);
+    }
+    if (flatFlags & SAVELAYERREC_HAS_FLAGS) {
+        this->addInt(rec.fSaveLayerFlags);
+    }
     this->validate(initialOffset, size);
 }
 
@@ -224,7 +249,8 @@ void SkPictureRecord::fillRestoreOffsetPlaceholdersForCurrentStackLevel(uint32_t
         uint32_t opSize;
         DrawType drawOp = peek_op_and_size(&fWriter, -offset, &opSize);
         SkASSERT(SAVE_LAYER_SAVEFLAGS_DEPRECATED != drawOp);
-        SkASSERT(SAVE == drawOp || SAVE_LAYER_SAVELAYERFLAGS == drawOp);
+        SkASSERT(SAVE_LAYER_SAVELAYERFLAGS_DEPRECATED_JAN_2016 != drawOp);
+        SkASSERT(SAVE == drawOp || SAVE_LAYER_SAVELAYERREC == drawOp);
     }
 #endif
 }
diff --git a/src/core/SkRecordDraw.cpp b/src/core/SkRecordDraw.cpp
index 01846676b6..5ca9517d3f 100644
--- a/src/core/SkRecordDraw.cpp
+++ b/src/core/SkRecordDraw.cpp
@@ -78,7 +78,7 @@ template <> void Draw::draw(const NoOp&) {}
 #define DRAW(T, call) template <> void Draw::draw(const T& r) { fCanvas->call; }
 DRAW(Restore, restore());
 DRAW(Save, save());
-DRAW(SaveLayer, saveLayer(SkCanvas::SaveLayerRec(r.bounds, r.paint, r.saveLayerFlags)));
+DRAW(SaveLayer, saveLayer(SkCanvas::SaveLayerRec(r.bounds, r.paint, r.backdrop, r.saveLayerFlags)));
 DRAW(SetMatrix, setMatrix(SkMatrix::Concat(fInitialCTM, r.matrix)));
 DRAW(Concat, concat(r.matrix));
 
diff --git a/src/core/SkRecorder.cpp b/src/core/SkRecorder.cpp
index 67429a691e..01c28dfc2b 100644
--- a/src/core/SkRecorder.cpp
+++ b/src/core/SkRecorder.cpp
@@ -337,7 +337,8 @@ void SkRecorder::willSave() {
 }
 
 SkCanvas::SaveLayerStrategy SkRecorder::getSaveLayerStrategy(const SaveLayerRec& rec) {
-    APPEND(SaveLayer, this->copy(rec.fBounds), this->copy(rec.fPaint), rec.fSaveLayerFlags);
+    APPEND(SaveLayer,
+           this->copy(rec.fBounds), this->copy(rec.fPaint), rec.fBackdrop, rec.fSaveLayerFlags);
     return SkCanvas::kNoLayer_SaveLayerStrategy;
 }