src/utils/SkDeferredCanvas.cpp - platform/external/skia - Gitiles

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */

 #include "SkDeferredCanvas.h"
 #include "SkDrawable.h"
 #include "SkPath.h"
 #include "SkRRect.h"
 #include "SkSurface.h"
 #include "SkTextBlob.h"
 #include "SkClipOpPriv.h"

 bool SkDeferredCanvas::Rec::isConcat(SkMatrix* m) const {
     switch (fType) {
         case kTrans_Type:
             m->setTranslate(fData.fTranslate.x(), fData.fTranslate.y());
             return true;
         case kScaleTrans_Type:
             m->setScaleTranslate(fData.fScaleTrans.fScale.x(),
                                  fData.fScaleTrans.fScale.y(),
                                  fData.fScaleTrans.fTrans.x(),
                                  fData.fScaleTrans.fTrans.y());
             return true;
         default:
             break;
     }
     return false;
 }

 void SkDeferredCanvas::Rec::setConcat(const SkMatrix& m) {
     SkASSERT(m.getType() <= (SkMatrix::kScale_Mask | SkMatrix::kTranslate_Mask));

     if (m.getType() <= SkMatrix::kTranslate_Mask) {
         fType = kTrans_Type;
         fData.fTranslate.set(m.getTranslateX(), m.getTranslateY());
     } else {
         fType = kScaleTrans_Type;
         fData.fScaleTrans.fScale.set(m.getScaleX(), m.getScaleY());
         fData.fScaleTrans.fTrans.set(m.getTranslateX(), m.getTranslateY());
     }
 }

 ///////////////////////////////////////////////////////////////////////////////////////////////////

 SkDeferredCanvas::SkDeferredCanvas(SkCanvas* canvas)
     : INHERITED(1, 1) {
     this->reset(canvas);
 }

 SkDeferredCanvas::~SkDeferredCanvas() {}

 void SkDeferredCanvas::reset(SkCanvas* canvas) {
     if (fCanvas) {
         this->flush();
         fCanvas = nullptr;
     }
     fRecs.reset();
     if (canvas) {
         this->resetForNextPicture(SkIRect::MakeSize(canvas->getBaseLayerSize()));
         fCanvas = canvas;
     }
 }

 void SkDeferredCanvas::push_save() {
     Rec* r = fRecs.append();
     r->fType = kSave_Type;
 }

 void SkDeferredCanvas::push_cliprect(const SkRect& bounds) {
     int index = fRecs.count() - 1;
     if (index >= 0 && fRecs[index].fType == kClipRect_Type) {
         if (!fRecs[index].fData.fBounds.intersect(bounds)) {
             fRecs[index].fData.fBounds.setEmpty();
         }
     } else {
         Rec* r = fRecs.append();
         r->fType = kClipRect_Type;
         r->fData.fBounds = bounds;
     }
 }

 bool SkDeferredCanvas::push_concat(const SkMatrix& mat) {
     if (mat.getType() > (SkMatrix::kScale_Mask | SkMatrix::kTranslate_Mask)) {
         return false;
     }
     // At the moment, we don't know which ops can scale and which can also flip, so
     // we reject negative scales for now
     if (mat.getScaleX() < 0 || mat.getScaleY() < 0) {
         return false;
     }

     int index = fRecs.count() - 1;
     SkMatrix m;
     if (index >= 0 && fRecs[index].isConcat(&m)) {
         m.preConcat(mat);
         fRecs[index].setConcat(m);
     } else {
         fRecs.append()->setConcat(mat);
     }
     return true;
 }

 void SkDeferredCanvas::emit(const Rec& rec) {
     switch (rec.fType) {
         case kSave_Type:
             fCanvas->save();
             this->INHERITED::willSave();
             break;
         case kClipRect_Type:
             fCanvas->clipRect(rec.fData.fBounds);
             this->INHERITED::onClipRect(rec.fData.fBounds,
                                         kIntersect_SkClipOp, kHard_ClipEdgeStyle);
             break;
         case kTrans_Type:
         case kScaleTrans_Type: {
             SkMatrix mat;
             rec.getConcat(&mat);
             fCanvas->concat(mat);
             this->INHERITED::didConcat(mat);
         } break;
     }
 }

 void SkDeferredCanvas::flush_le(int index) {
     SkASSERT(index >= -1 && index < fRecs.count());

     int count = index + 1;
     for (int i = 0; i < count; ++i) {
         this->emit(fRecs[i]);
     }
     fRecs.remove(0, count);
 }

 void SkDeferredCanvas::flush_all() {
     this->flush_le(fRecs.count() - 1);
 }

 void SkDeferredCanvas::flush_before_saves() {
     int i;
     for (i = fRecs.count() - 1; i >= 0; --i) {
         if (kSave_Type != fRecs[i].fType) {
             break;
         }
     }
     this->flush_le(i);
 }

 enum Flags {
     kNoTranslate_Flag   = 1 << 0,
     kNoClip_Flag        = 1 << 1,
     kNoCull_Flag        = 1 << 2,
     kNoScale_Flag       = 1 << 3,
 };

 void SkDeferredCanvas::flush_check(SkRect* bounds, const SkPaint* paint, unsigned flags) {
     if (paint) {
         if (paint->getShader() || paint->getImageFilter()) {
             flags |= kNoTranslate_Flag | kNoScale_Flag;
         }
         // TODO: replace these with code to enlarge the bounds conservatively?
         if (paint->getStyle() != SkPaint::kFill_Style || paint->getMaskFilter() ||
             paint->getImageFilter() || paint->getPathEffect())
         {
             flags |= kNoCull_Flag | kNoScale_Flag | kNoClip_Flag;
         }
         if (paint->getLooper()) {
             // to be conservative, we disable both, since embedded layers could have shaders
             // or strokes etc.
             flags |= kNoTranslate_Flag | kNoCull_Flag | kNoScale_Flag;
         }
     }
     bool canClip = !(flags & kNoClip_Flag);
     bool canTranslate = !(flags & kNoTranslate_Flag);
     bool canCull = !(flags & kNoCull_Flag);
     bool canScale = !(flags & kNoScale_Flag);

     int i;
     for (i = fRecs.count() - 1; i >= 0; --i) {
         const Rec& rec = fRecs[i];
         switch (rec.fType) {
             case kSave_Type:
                 // continue to the next rec
                 break;
             case kClipRect_Type:
                 if (!canCull) {
                     goto STOP;
                 }
                 if (canClip) {
                     if (!bounds->intersect(rec.fData.fBounds)) {
                         bounds->setEmpty();
                         return;
                     }
                     // continue to the next rec
                 } else {
                     if (!rec.fData.fBounds.contains(*bounds)) {
                         goto STOP;
                     }
                     // continue to the next rec
                 }
                 break;
             case kTrans_Type:
                 if (canTranslate) {
                     bounds->offset(rec.fData.fTranslate.x(), rec.fData.fTranslate.y());
                     // continue to the next rec
                 } else {
                     goto STOP;
                 }
                 break;
             case kScaleTrans_Type:
                 if (canScale) {
                     SkMatrix m;
                     rec.getConcat(&m);
                     m.mapRectScaleTranslate(bounds, *bounds);
                 } else {
                     goto STOP;
                 }
                 break;
         }
     }
 STOP:
     this->flush_le(i);
 }

 void SkDeferredCanvas::flush_translate(SkScalar* x, SkScalar* y, const SkRect& bounds,
                                        const SkPaint* paint) {
     SkRect tmp = bounds;
     this->flush_check(&tmp, paint, kNoClip_Flag | kNoScale_Flag);
     *x += tmp.x() - bounds.x();
     *y += tmp.y() - bounds.y();
 }

 void SkDeferredCanvas::flush_translate(SkScalar* x, SkScalar* y, const SkPaint& paint) {
     SkRect tmp = SkRect::MakeXYWH(*x, *y, 1, 1);
     this->flush_check(&tmp, &paint, kNoClip_Flag | kNoCull_Flag | kNoScale_Flag);
     *x = tmp.x();
     *y = tmp.y();
 }

 ///////////////////////////////////////////////////////////////////////////////////////////////////

 void SkDeferredCanvas::willSave() {
     this->push_save();
 }

 SkCanvas::SaveLayerStrategy SkDeferredCanvas::getSaveLayerStrategy(const SaveLayerRec& rec) {
     this->flush_all();
     fCanvas->saveLayer(rec);
     this->INHERITED::getSaveLayerStrategy(rec);
     // No need for a layer.
     return kNoLayer_SaveLayerStrategy;
 }

 void SkDeferredCanvas::willRestore() {
     for (int i = fRecs.count() - 1; i >= 0; --i) {
         if (kSave_Type == fRecs[i].fType) {
             fRecs.setCount(i);  // pop off everything here and later
             return;
         }
     }
     for (int i = 0; i < fRecs.count(); ++i) {
         SkASSERT(kSave_Type != fRecs[i].fType);
     }
     fRecs.setCount(0);
     fCanvas->restore();
     this->INHERITED::willRestore();
 }

 void SkDeferredCanvas::didConcat(const SkMatrix& matrix) {
     if (matrix.isIdentity()) {
         return;
     }
     if (!this->push_concat(matrix)) {
         this->flush_all();
         fCanvas->concat(matrix);
         this->INHERITED::didConcat(matrix);
     }
 }

 void SkDeferredCanvas::didSetMatrix(const SkMatrix& matrix) {
     this->flush_all();
     fCanvas->setMatrix(matrix);
     this->INHERITED::didSetMatrix(matrix);
 }

 void SkDeferredCanvas::onClipRect(const SkRect& rect, SkClipOp op, ClipEdgeStyle edgeStyle) {
     if (kIntersect_SkClipOp == op) {
         this->push_cliprect(rect);
     } else {
         this->flush_all();
         fCanvas->clipRect(rect, op, kSoft_ClipEdgeStyle == edgeStyle);
         this->INHERITED::onClipRect(rect, op, edgeStyle);
     }
 }

 void SkDeferredCanvas::onClipRRect(const SkRRect& rrect, SkClipOp op, ClipEdgeStyle edgeStyle) {
     this->flush_all();
     fCanvas->clipRRect(rrect, op, kSoft_ClipEdgeStyle == edgeStyle);
     this->INHERITED::onClipRRect(rrect, op, edgeStyle);
 }

 void SkDeferredCanvas::onClipPath(const SkPath& path, SkClipOp op, ClipEdgeStyle edgeStyle) {
     this->flush_all();
     fCanvas->clipPath(path, op, kSoft_ClipEdgeStyle == edgeStyle);
     this->INHERITED::onClipPath(path, op, edgeStyle);
 }

 void SkDeferredCanvas::onClipRegion(const SkRegion& deviceRgn, SkClipOp op) {
     this->flush_all();
     fCanvas->clipRegion(deviceRgn, op);
     this->INHERITED::onClipRegion(deviceRgn, op);
 }

 void SkDeferredCanvas::onDrawPaint(const SkPaint& paint) {
     // TODO: Can we turn this into drawRect?
     this->flush_all();
     fCanvas->drawPaint(paint);
 }

 void SkDeferredCanvas::onDrawPoints(PointMode mode, size_t count, const SkPoint pts[],
                                 const SkPaint& paint) {
     this->flush_all();
     fCanvas->drawPoints(mode, count, pts, paint);
 }

 void SkDeferredCanvas::onDrawRect(const SkRect& rect, const SkPaint& paint) {
     SkRect modRect = rect;
     this->flush_check(&modRect, &paint);
     fCanvas->drawRect(modRect, paint);
 }

 void SkDeferredCanvas::onDrawRegion(const SkRegion& region, const SkPaint& paint) {
     this->flush_all();  // can we do better?
     fCanvas->drawRegion(region, paint);
 }

 void SkDeferredCanvas::onDrawOval(const SkRect& rect, const SkPaint& paint) {
     SkRect modRect = rect;
     this->flush_check(&modRect, &paint, kNoClip_Flag);
     fCanvas->drawOval(modRect, paint);
 }

 void SkDeferredCanvas::onDrawArc(const SkRect& rect, SkScalar startAngle, SkScalar sweepAngle,
                                  bool useCenter, const SkPaint& paint) {
     SkRect modRect = rect;
     this->flush_check(&modRect, &paint, kNoClip_Flag);
     fCanvas->drawArc(modRect, startAngle, sweepAngle, useCenter, paint);
 }

 static SkRRect make_offset(const SkRRect& src, SkScalar dx, SkScalar dy) {
     SkRRect dst = src;
     dst.offset(dx, dy);
     return dst;
 }

 void SkDeferredCanvas::onDrawRRect(const SkRRect& rrect, const SkPaint& paint) {
     SkRect modRect = rrect.getBounds();
     this->flush_check(&modRect, &paint, kNoClip_Flag);
     fCanvas->drawRRect(make_offset(rrect,
                                    modRect.x() - rrect.getBounds().x(),
                                    modRect.y() - rrect.getBounds().y()), paint);
 }

 void SkDeferredCanvas::onDrawDRRect(const SkRRect& outer, const SkRRect& inner, const SkPaint& paint) {
     this->flush_all();
     fCanvas->drawDRRect(outer, inner, paint);
 }

 void SkDeferredCanvas::onDrawPath(const SkPath& path, const SkPaint& paint) {
     if (path.isInverseFillType()) {
         this->flush_before_saves();
     } else {
         SkRect modRect = path.getBounds();
         this->flush_check(&modRect, &paint, kNoClip_Flag | kNoTranslate_Flag | kNoScale_Flag);
     }
     fCanvas->drawPath(path, paint);
 }

 void SkDeferredCanvas::onDrawBitmap(const SkBitmap& bitmap, SkScalar x, SkScalar y,
                                 const SkPaint* paint) {
     const SkScalar w = SkIntToScalar(bitmap.width());
     const SkScalar h = SkIntToScalar(bitmap.height());
     SkRect bounds = SkRect::MakeXYWH(x, y, w, h);
     this->flush_check(&bounds, paint, kNoClip_Flag);
     if (bounds.width() == w && bounds.height() == h) {
         fCanvas->drawBitmap(bitmap, bounds.x(), bounds.y(), paint);
     } else {
         fCanvas->drawBitmapRect(bitmap, bounds, paint);
     }
 }

 void SkDeferredCanvas::onDrawBitmapRect(const SkBitmap& bitmap, const SkRect* src, const SkRect& dst,
                                     const SkPaint* paint, SrcRectConstraint constraint) {
     SkRect modRect = dst;
     this->flush_check(&modRect, paint, kNoClip_Flag);
     fCanvas->legacy_drawBitmapRect(bitmap, src, modRect, paint, constraint);
 }

 void SkDeferredCanvas::onDrawBitmapNine(const SkBitmap& bitmap, const SkIRect& center,
                                     const SkRect& dst, const SkPaint* paint) {
     SkRect modRect = dst;
     this->flush_check(&modRect, paint, kNoClip_Flag);
     fCanvas->drawBitmapNine(bitmap, center, modRect, paint);
 }

 void SkDeferredCanvas::onDrawBitmapLattice(const SkBitmap& bitmap, const Lattice& lattice,
                                            const SkRect& dst, const SkPaint* paint) {
     SkRect modRect = dst;
     this->flush_check(&modRect, paint, kNoClip_Flag);
     fCanvas->drawBitmapLattice(bitmap, lattice, modRect, paint);
 }

 void SkDeferredCanvas::onDrawImageNine(const SkImage* image, const SkIRect& center,
                                        const SkRect& dst, const SkPaint* paint) {
     SkRect modRect = dst;
     this->flush_check(&modRect, paint, kNoClip_Flag);
     fCanvas->drawImageNine(image, center, modRect, paint);
 }

 void SkDeferredCanvas::onDrawImage(const SkImage* image, SkScalar x, SkScalar y,
                                    const SkPaint* paint) {
     const SkScalar w = SkIntToScalar(image->width());
     const SkScalar h = SkIntToScalar(image->height());
     SkRect bounds = SkRect::MakeXYWH(x, y, w, h);
     this->flush_check(&bounds, paint, kNoClip_Flag);
     if (bounds.width() == w && bounds.height() == h) {
         fCanvas->drawImage(image, bounds.x(), bounds.y(), paint);
     } else {
         fCanvas->drawImageRect(image, bounds, paint);
     }
 }

 void SkDeferredCanvas::onDrawImageRect(const SkImage* image, const SkRect* src, const SkRect& dst,
                                    const SkPaint* paint, SrcRectConstraint constraint) {
     SkRect modRect = dst;
     this->flush_check(&modRect, paint, kNoClip_Flag);
     fCanvas->legacy_drawImageRect(image, src, modRect, paint, constraint);
 }

 void SkDeferredCanvas::onDrawImageLattice(const SkImage* image, const Lattice& lattice,
                                           const SkRect& dst, const SkPaint* paint) {
     SkRect modRect = dst;
     this->flush_check(&modRect, paint, kNoClip_Flag);
     fCanvas->drawImageLattice(image, lattice, modRect, paint);
 }

 void SkDeferredCanvas::onDrawText(const void* text, size_t byteLength, SkScalar x, SkScalar y,
                                   const SkPaint& paint) {
     this->flush_translate(&x, &y, paint);
     fCanvas->drawText(text, byteLength, x, y, paint);
 }

 void SkDeferredCanvas::onDrawPosText(const void* text, size_t byteLength, const SkPoint pos[],
                                  const SkPaint& paint) {
     this->flush_before_saves();
     fCanvas->drawPosText(text, byteLength, pos, paint);
 }

 void SkDeferredCanvas::onDrawPosTextH(const void* text, size_t byteLength, const SkScalar xpos[],
                                   SkScalar constY, const SkPaint& paint) {
     this->flush_before_saves();
     fCanvas->drawPosTextH(text, byteLength, xpos, constY, paint);
 }

 void SkDeferredCanvas::onDrawTextOnPath(const void* text, size_t byteLength, const SkPath& path,
                                     const SkMatrix* matrix, const SkPaint& paint) {
     this->flush_before_saves();
     fCanvas->drawTextOnPath(text, byteLength, path, matrix, paint);
 }

 void SkDeferredCanvas::onDrawTextRSXform(const void* text, size_t byteLength,
                                          const SkRSXform xform[], const SkRect* cullRect,
                                          const SkPaint& paint) {
     if (cullRect) {
         SkRect modRect = *cullRect;
         // only allow culling
         this->flush_check(&modRect, &paint, kNoClip_Flag | kNoScale_Flag | kNoTranslate_Flag);
     } else {
         this->flush_before_saves();
     }
     fCanvas->drawTextRSXform(text, byteLength, xform, cullRect, paint);
 }

 void SkDeferredCanvas::onDrawTextBlob(const SkTextBlob* blob, SkScalar x, SkScalar y,
                                   const SkPaint &paint) {
     this->flush_translate(&x, &y, blob->bounds(), &paint);
     fCanvas->drawTextBlob(blob, x, y, paint);
 }

 #include "SkPicture.h"
 #include "SkCanvasPriv.h"
 void SkDeferredCanvas::onDrawPicture(const SkPicture* picture, const SkMatrix* matrix,
                                  const SkPaint* paint) {
 #if 0
     SkAutoCanvasMatrixPaint acmp(this, matrix, paint, picture->cullRect());
     picture->playback(this);
 #else
     this->flush_before_saves();
     fCanvas->drawPicture(picture, matrix, paint);
 #endif
 }

 void SkDeferredCanvas::onDrawDrawable(SkDrawable* drawable, const SkMatrix* matrix) {
     // TODO: investigate culling and applying concat to the matrix
 #if 0
     drawable->draw(this, matrix);
 #else
     this->flush_before_saves();
     fCanvas->drawDrawable(drawable, matrix);
 #endif
 }

 void SkDeferredCanvas::onDrawAtlas(const SkImage* image, const SkRSXform xform[],
                                    const SkRect rects[], const SkColor colors[],
                                    int count, SkBlendMode bmode,
                                    const SkRect* cull, const SkPaint* paint) {
     this->flush_before_saves();
     fCanvas->drawAtlas(image, xform, rects, colors, count, bmode, cull, paint);
 }

 void SkDeferredCanvas::onDrawVertices(VertexMode vmode, int vertexCount,
                                   const SkPoint vertices[], const SkPoint texs[],
                                   const SkColor colors[], SkBlendMode bmode,
                                   const uint16_t indices[], int indexCount,
                                   const SkPaint& paint) {
     this->flush_before_saves();
     fCanvas->drawVertices(vmode, vertexCount, vertices, texs, colors, bmode,
                            indices, indexCount, paint);
 }

 void SkDeferredCanvas::onDrawPatch(const SkPoint cubics[12], const SkColor colors[4],
                                const SkPoint texCoords[4], SkBlendMode bmode,
                                const SkPaint& paint) {
     this->flush_before_saves();
     fCanvas->drawPatch(cubics, colors, texCoords, bmode, paint);
 }

 void SkDeferredCanvas::onDrawAnnotation(const SkRect& rect, const char key[], SkData* data) {
     SkRect modRect = rect;
     this->flush_check(&modRect, nullptr, kNoClip_Flag);
     fCanvas->drawAnnotation(modRect, key, data);
 }

 #ifdef SK_SUPPORT_LEGACY_DRAWFILTER
 SkDrawFilter* SkDeferredCanvas::setDrawFilter(SkDrawFilter* filter) {
     fCanvas->setDrawFilter(filter);
     return this->INHERITED::setDrawFilter(filter);
 }
 #endif

 ///////////////////////////////////////////////////////////////////////////////////////////////////

 sk_sp<SkSurface> SkDeferredCanvas::onNewSurface(const SkImageInfo& info,
                                                 const SkSurfaceProps& props) {
     return fCanvas->makeSurface(info, &props);
 }
 SkISize SkDeferredCanvas::getBaseLayerSize() const { return fCanvas->getBaseLayerSize(); }
 SkRect SkDeferredCanvas::onGetLocalClipBounds() const {
     return fCanvas->getLocalClipBounds();
 }
 SkIRect SkDeferredCanvas::onGetDeviceClipBounds() const {
     return fCanvas->getDeviceClipBounds();
 }
 bool SkDeferredCanvas::isClipEmpty() const { return fCanvas->isClipEmpty(); }
 bool SkDeferredCanvas::isClipRect() const { return fCanvas->isClipRect(); }
 bool SkDeferredCanvas::onPeekPixels(SkPixmap* pixmap) { return fCanvas->peekPixels(pixmap); }
 bool SkDeferredCanvas::onAccessTopLayerPixels(SkPixmap* pixmap) {
     SkImageInfo info;
     size_t rowBytes;
     SkIPoint* origin = nullptr;
     void* addr = fCanvas->accessTopLayerPixels(&info, &rowBytes, origin);
     if (addr) {
         *pixmap = SkPixmap(info, addr, rowBytes);
         return true;
     }
     return false;
 }
 SkImageInfo SkDeferredCanvas::onImageInfo() const { return fCanvas->imageInfo(); }
 bool SkDeferredCanvas::onGetProps(SkSurfaceProps* props) const { return fCanvas->getProps(props); }
 void SkDeferredCanvas::onFlush() {
     this->flush_all();
     return fCanvas->flush();
 }
	/*
	* Copyright 2016 Google Inc.
	*
	* Use of this source code is governed by a BSD-style license that can be
	* found in the LICENSE file.
	*/

	#include "SkDeferredCanvas.h"
	#include "SkDrawable.h"
	#include "SkPath.h"
	#include "SkRRect.h"
	#include "SkSurface.h"
	#include "SkTextBlob.h"
	#include "SkClipOpPriv.h"

	bool SkDeferredCanvas::Rec::isConcat(SkMatrix* m) const {
	switch (fType) {
	case kTrans_Type:
	m->setTranslate(fData.fTranslate.x(), fData.fTranslate.y());
	return true;
	case kScaleTrans_Type:
	m->setScaleTranslate(fData.fScaleTrans.fScale.x(),
	fData.fScaleTrans.fScale.y(),
	fData.fScaleTrans.fTrans.x(),
	fData.fScaleTrans.fTrans.y());
	return true;
	default:
	break;
	}
	return false;
	}

	void SkDeferredCanvas::Rec::setConcat(const SkMatrix& m) {
	SkASSERT(m.getType() <= (SkMatrix::kScale_Mask \| SkMatrix::kTranslate_Mask));

	if (m.getType() <= SkMatrix::kTranslate_Mask) {
	fType = kTrans_Type;
	fData.fTranslate.set(m.getTranslateX(), m.getTranslateY());
	} else {
	fType = kScaleTrans_Type;
	fData.fScaleTrans.fScale.set(m.getScaleX(), m.getScaleY());
	fData.fScaleTrans.fTrans.set(m.getTranslateX(), m.getTranslateY());
	}
	}

	///////////////////////////////////////////////////////////////////////////////////////////////////

	SkDeferredCanvas::SkDeferredCanvas(SkCanvas* canvas)
	: INHERITED(1, 1) {
	this->reset(canvas);
	}

	SkDeferredCanvas::~SkDeferredCanvas() {}

	void SkDeferredCanvas::reset(SkCanvas* canvas) {
	if (fCanvas) {
	this->flush();
	fCanvas = nullptr;
	}
	fRecs.reset();
	if (canvas) {
	this->resetForNextPicture(SkIRect::MakeSize(canvas->getBaseLayerSize()));
	fCanvas = canvas;
	}
	}

	void SkDeferredCanvas::push_save() {
	Rec* r = fRecs.append();
	r->fType = kSave_Type;
	}

	void SkDeferredCanvas::push_cliprect(const SkRect& bounds) {
	int index = fRecs.count() - 1;
	if (index >= 0 && fRecs[index].fType == kClipRect_Type) {
	if (!fRecs[index].fData.fBounds.intersect(bounds)) {
	fRecs[index].fData.fBounds.setEmpty();
	}
	} else {
	Rec* r = fRecs.append();
	r->fType = kClipRect_Type;
	r->fData.fBounds = bounds;
	}
	}

	bool SkDeferredCanvas::push_concat(const SkMatrix& mat) {
	if (mat.getType() > (SkMatrix::kScale_Mask \| SkMatrix::kTranslate_Mask)) {
	return false;
	}
	// At the moment, we don't know which ops can scale and which can also flip, so
	// we reject negative scales for now
	if (mat.getScaleX() < 0 \|\| mat.getScaleY() < 0) {
	return false;
	}

	int index = fRecs.count() - 1;
	SkMatrix m;
	if (index >= 0 && fRecs[index].isConcat(&m)) {
	m.preConcat(mat);
	fRecs[index].setConcat(m);
	} else {
	fRecs.append()->setConcat(mat);
	}
	return true;
	}

	void SkDeferredCanvas::emit(const Rec& rec) {
	switch (rec.fType) {
	case kSave_Type:
	fCanvas->save();
	this->INHERITED::willSave();
	break;
	case kClipRect_Type:
	fCanvas->clipRect(rec.fData.fBounds);
	this->INHERITED::onClipRect(rec.fData.fBounds,
	kIntersect_SkClipOp, kHard_ClipEdgeStyle);
	break;
	case kTrans_Type:
	case kScaleTrans_Type: {
	SkMatrix mat;
	rec.getConcat(&mat);
	fCanvas->concat(mat);
	this->INHERITED::didConcat(mat);
	} break;
	}
	}

	void SkDeferredCanvas::flush_le(int index) {
	SkASSERT(index >= -1 && index < fRecs.count());

	int count = index + 1;
	for (int i = 0; i < count; ++i) {
	this->emit(fRecs[i]);
	}
	fRecs.remove(0, count);
	}

	void SkDeferredCanvas::flush_all() {
	this->flush_le(fRecs.count() - 1);
	}

	void SkDeferredCanvas::flush_before_saves() {
	int i;
	for (i = fRecs.count() - 1; i >= 0; --i) {
	if (kSave_Type != fRecs[i].fType) {
	break;
	}
	}
	this->flush_le(i);
	}

	enum Flags {
	kNoTranslate_Flag = 1 << 0,
	kNoClip_Flag = 1 << 1,
	kNoCull_Flag = 1 << 2,
	kNoScale_Flag = 1 << 3,
	};

	void SkDeferredCanvas::flush_check(SkRect* bounds, const SkPaint* paint, unsigned flags) {
	if (paint) {
	if (paint->getShader() \|\| paint->getImageFilter()) {
	flags \|= kNoTranslate_Flag \| kNoScale_Flag;
	}
	// TODO: replace these with code to enlarge the bounds conservatively?
	if (paint->getStyle() != SkPaint::kFill_Style \|\| paint->getMaskFilter() \|\|
	paint->getImageFilter() \|\| paint->getPathEffect())
	{
	flags \|= kNoCull_Flag \| kNoScale_Flag \| kNoClip_Flag;
	}
	if (paint->getLooper()) {
	// to be conservative, we disable both, since embedded layers could have shaders
	// or strokes etc.
	flags \|= kNoTranslate_Flag \| kNoCull_Flag \| kNoScale_Flag;
	}
	}
	bool canClip = !(flags & kNoClip_Flag);
	bool canTranslate = !(flags & kNoTranslate_Flag);
	bool canCull = !(flags & kNoCull_Flag);
	bool canScale = !(flags & kNoScale_Flag);

	int i;
	for (i = fRecs.count() - 1; i >= 0; --i) {
	const Rec& rec = fRecs[i];
	switch (rec.fType) {
	case kSave_Type:
	// continue to the next rec
	break;
	case kClipRect_Type:
	if (!canCull) {
	goto STOP;
	}
	if (canClip) {
	if (!bounds->intersect(rec.fData.fBounds)) {
	bounds->setEmpty();
	return;
	}
	// continue to the next rec
	} else {
	if (!rec.fData.fBounds.contains(*bounds)) {
	goto STOP;
	}
	// continue to the next rec
	}
	break;
	case kTrans_Type:
	if (canTranslate) {
	bounds->offset(rec.fData.fTranslate.x(), rec.fData.fTranslate.y());
	// continue to the next rec
	} else {
	goto STOP;
	}
	break;
	case kScaleTrans_Type:
	if (canScale) {
	SkMatrix m;
	rec.getConcat(&m);
	m.mapRectScaleTranslate(bounds, *bounds);
	} else {
	goto STOP;
	}
	break;
	}
	}
	STOP:
	this->flush_le(i);
	}

	void SkDeferredCanvas::flush_translate(SkScalar* x, SkScalar* y, const SkRect& bounds,
	const SkPaint* paint) {
	SkRect tmp = bounds;
	this->flush_check(&tmp, paint, kNoClip_Flag \| kNoScale_Flag);
	*x += tmp.x() - bounds.x();
	*y += tmp.y() - bounds.y();
	}

	void SkDeferredCanvas::flush_translate(SkScalar* x, SkScalar* y, const SkPaint& paint) {
	SkRect tmp = SkRect::MakeXYWH(x, y, 1, 1);
	this->flush_check(&tmp, &paint, kNoClip_Flag \| kNoCull_Flag \| kNoScale_Flag);
	*x = tmp.x();
	*y = tmp.y();
	}

	///////////////////////////////////////////////////////////////////////////////////////////////////

	void SkDeferredCanvas::willSave() {
	this->push_save();
	}

	SkCanvas::SaveLayerStrategy SkDeferredCanvas::getSaveLayerStrategy(const SaveLayerRec& rec) {
	this->flush_all();
	fCanvas->saveLayer(rec);
	this->INHERITED::getSaveLayerStrategy(rec);
	// No need for a layer.
	return kNoLayer_SaveLayerStrategy;
	}

	void SkDeferredCanvas::willRestore() {
	for (int i = fRecs.count() - 1; i >= 0; --i) {
	if (kSave_Type == fRecs[i].fType) {
	fRecs.setCount(i); // pop off everything here and later
	return;
	}
	}
	for (int i = 0; i < fRecs.count(); ++i) {
	SkASSERT(kSave_Type != fRecs[i].fType);
	}
	fRecs.setCount(0);
	fCanvas->restore();
	this->INHERITED::willRestore();
	}

	void SkDeferredCanvas::didConcat(const SkMatrix& matrix) {
	if (matrix.isIdentity()) {
	return;
	}
	if (!this->push_concat(matrix)) {
	this->flush_all();
	fCanvas->concat(matrix);
	this->INHERITED::didConcat(matrix);
	}
	}

	void SkDeferredCanvas::didSetMatrix(const SkMatrix& matrix) {
	this->flush_all();
	fCanvas->setMatrix(matrix);
	this->INHERITED::didSetMatrix(matrix);
	}

	void SkDeferredCanvas::onClipRect(const SkRect& rect, SkClipOp op, ClipEdgeStyle edgeStyle) {
	if (kIntersect_SkClipOp == op) {
	this->push_cliprect(rect);
	} else {
	this->flush_all();
	fCanvas->clipRect(rect, op, kSoft_ClipEdgeStyle == edgeStyle);
	this->INHERITED::onClipRect(rect, op, edgeStyle);
	}
	}

	void SkDeferredCanvas::onClipRRect(const SkRRect& rrect, SkClipOp op, ClipEdgeStyle edgeStyle) {
	this->flush_all();
	fCanvas->clipRRect(rrect, op, kSoft_ClipEdgeStyle == edgeStyle);
	this->INHERITED::onClipRRect(rrect, op, edgeStyle);
	}

	void SkDeferredCanvas::onClipPath(const SkPath& path, SkClipOp op, ClipEdgeStyle edgeStyle) {
	this->flush_all();
	fCanvas->clipPath(path, op, kSoft_ClipEdgeStyle == edgeStyle);
	this->INHERITED::onClipPath(path, op, edgeStyle);
	}

	void SkDeferredCanvas::onClipRegion(const SkRegion& deviceRgn, SkClipOp op) {
	this->flush_all();
	fCanvas->clipRegion(deviceRgn, op);
	this->INHERITED::onClipRegion(deviceRgn, op);
	}

	void SkDeferredCanvas::onDrawPaint(const SkPaint& paint) {
	// TODO: Can we turn this into drawRect?
	this->flush_all();
	fCanvas->drawPaint(paint);
	}

	void SkDeferredCanvas::onDrawPoints(PointMode mode, size_t count, const SkPoint pts[],
	const SkPaint& paint) {
	this->flush_all();
	fCanvas->drawPoints(mode, count, pts, paint);
	}

	void SkDeferredCanvas::onDrawRect(const SkRect& rect, const SkPaint& paint) {
	SkRect modRect = rect;
	this->flush_check(&modRect, &paint);
	fCanvas->drawRect(modRect, paint);
	}

	void SkDeferredCanvas::onDrawRegion(const SkRegion& region, const SkPaint& paint) {
	this->flush_all(); // can we do better?
	fCanvas->drawRegion(region, paint);
	}

	void SkDeferredCanvas::onDrawOval(const SkRect& rect, const SkPaint& paint) {
	SkRect modRect = rect;
	this->flush_check(&modRect, &paint, kNoClip_Flag);
	fCanvas->drawOval(modRect, paint);
	}

	void SkDeferredCanvas::onDrawArc(const SkRect& rect, SkScalar startAngle, SkScalar sweepAngle,
	bool useCenter, const SkPaint& paint) {
	SkRect modRect = rect;
	this->flush_check(&modRect, &paint, kNoClip_Flag);
	fCanvas->drawArc(modRect, startAngle, sweepAngle, useCenter, paint);
	}

	static SkRRect make_offset(const SkRRect& src, SkScalar dx, SkScalar dy) {
	SkRRect dst = src;
	dst.offset(dx, dy);
	return dst;
	}

	void SkDeferredCanvas::onDrawRRect(const SkRRect& rrect, const SkPaint& paint) {
	SkRect modRect = rrect.getBounds();
	this->flush_check(&modRect, &paint, kNoClip_Flag);
	fCanvas->drawRRect(make_offset(rrect,
	modRect.x() - rrect.getBounds().x(),
	modRect.y() - rrect.getBounds().y()), paint);
	}

	void SkDeferredCanvas::onDrawDRRect(const SkRRect& outer, const SkRRect& inner, const SkPaint& paint) {
	this->flush_all();
	fCanvas->drawDRRect(outer, inner, paint);
	}

	void SkDeferredCanvas::onDrawPath(const SkPath& path, const SkPaint& paint) {
	if (path.isInverseFillType()) {
	this->flush_before_saves();
	} else {
	SkRect modRect = path.getBounds();
	this->flush_check(&modRect, &paint, kNoClip_Flag \| kNoTranslate_Flag \| kNoScale_Flag);
	}
	fCanvas->drawPath(path, paint);
	}

	void SkDeferredCanvas::onDrawBitmap(const SkBitmap& bitmap, SkScalar x, SkScalar y,
	const SkPaint* paint) {
	const SkScalar w = SkIntToScalar(bitmap.width());
	const SkScalar h = SkIntToScalar(bitmap.height());
	SkRect bounds = SkRect::MakeXYWH(x, y, w, h);
	this->flush_check(&bounds, paint, kNoClip_Flag);
	if (bounds.width() == w && bounds.height() == h) {
	fCanvas->drawBitmap(bitmap, bounds.x(), bounds.y(), paint);
	} else {
	fCanvas->drawBitmapRect(bitmap, bounds, paint);
	}
	}

	void SkDeferredCanvas::onDrawBitmapRect(const SkBitmap& bitmap, const SkRect* src, const SkRect& dst,
	const SkPaint* paint, SrcRectConstraint constraint) {
	SkRect modRect = dst;
	this->flush_check(&modRect, paint, kNoClip_Flag);
	fCanvas->legacy_drawBitmapRect(bitmap, src, modRect, paint, constraint);
	}

	void SkDeferredCanvas::onDrawBitmapNine(const SkBitmap& bitmap, const SkIRect& center,
	const SkRect& dst, const SkPaint* paint) {
	SkRect modRect = dst;
	this->flush_check(&modRect, paint, kNoClip_Flag);
	fCanvas->drawBitmapNine(bitmap, center, modRect, paint);
	}

	void SkDeferredCanvas::onDrawBitmapLattice(const SkBitmap& bitmap, const Lattice& lattice,
	const SkRect& dst, const SkPaint* paint) {
	SkRect modRect = dst;
	this->flush_check(&modRect, paint, kNoClip_Flag);
	fCanvas->drawBitmapLattice(bitmap, lattice, modRect, paint);
	}

	void SkDeferredCanvas::onDrawImageNine(const SkImage* image, const SkIRect& center,
	const SkRect& dst, const SkPaint* paint) {
	SkRect modRect = dst;
	this->flush_check(&modRect, paint, kNoClip_Flag);
	fCanvas->drawImageNine(image, center, modRect, paint);
	}

	void SkDeferredCanvas::onDrawImage(const SkImage* image, SkScalar x, SkScalar y,
	const SkPaint* paint) {
	const SkScalar w = SkIntToScalar(image->width());
	const SkScalar h = SkIntToScalar(image->height());
	SkRect bounds = SkRect::MakeXYWH(x, y, w, h);
	this->flush_check(&bounds, paint, kNoClip_Flag);
	if (bounds.width() == w && bounds.height() == h) {
	fCanvas->drawImage(image, bounds.x(), bounds.y(), paint);
	} else {
	fCanvas->drawImageRect(image, bounds, paint);
	}
	}

	void SkDeferredCanvas::onDrawImageRect(const SkImage* image, const SkRect* src, const SkRect& dst,
	const SkPaint* paint, SrcRectConstraint constraint) {
	SkRect modRect = dst;
	this->flush_check(&modRect, paint, kNoClip_Flag);
	fCanvas->legacy_drawImageRect(image, src, modRect, paint, constraint);
	}

	void SkDeferredCanvas::onDrawImageLattice(const SkImage* image, const Lattice& lattice,
	const SkRect& dst, const SkPaint* paint) {
	SkRect modRect = dst;
	this->flush_check(&modRect, paint, kNoClip_Flag);
	fCanvas->drawImageLattice(image, lattice, modRect, paint);
	}

	void SkDeferredCanvas::onDrawText(const void* text, size_t byteLength, SkScalar x, SkScalar y,
	const SkPaint& paint) {
	this->flush_translate(&x, &y, paint);
	fCanvas->drawText(text, byteLength, x, y, paint);
	}

	void SkDeferredCanvas::onDrawPosText(const void* text, size_t byteLength, const SkPoint pos[],
	const SkPaint& paint) {
	this->flush_before_saves();
	fCanvas->drawPosText(text, byteLength, pos, paint);
	}

	void SkDeferredCanvas::onDrawPosTextH(const void* text, size_t byteLength, const SkScalar xpos[],
	SkScalar constY, const SkPaint& paint) {
	this->flush_before_saves();
	fCanvas->drawPosTextH(text, byteLength, xpos, constY, paint);
	}

	void SkDeferredCanvas::onDrawTextOnPath(const void* text, size_t byteLength, const SkPath& path,
	const SkMatrix* matrix, const SkPaint& paint) {
	this->flush_before_saves();
	fCanvas->drawTextOnPath(text, byteLength, path, matrix, paint);
	}

	void SkDeferredCanvas::onDrawTextRSXform(const void* text, size_t byteLength,
	const SkRSXform xform[], const SkRect* cullRect,
	const SkPaint& paint) {
	if (cullRect) {
	SkRect modRect = *cullRect;
	// only allow culling
	this->flush_check(&modRect, &paint, kNoClip_Flag \| kNoScale_Flag \| kNoTranslate_Flag);
	} else {
	this->flush_before_saves();
	}
	fCanvas->drawTextRSXform(text, byteLength, xform, cullRect, paint);
	}

	void SkDeferredCanvas::onDrawTextBlob(const SkTextBlob* blob, SkScalar x, SkScalar y,
	const SkPaint &paint) {
	this->flush_translate(&x, &y, blob->bounds(), &paint);
	fCanvas->drawTextBlob(blob, x, y, paint);
	}

	#include "SkPicture.h"
	#include "SkCanvasPriv.h"
	void SkDeferredCanvas::onDrawPicture(const SkPicture* picture, const SkMatrix* matrix,
	const SkPaint* paint) {
	#if 0
	SkAutoCanvasMatrixPaint acmp(this, matrix, paint, picture->cullRect());
	picture->playback(this);
	#else
	this->flush_before_saves();
	fCanvas->drawPicture(picture, matrix, paint);
	#endif
	}

	void SkDeferredCanvas::onDrawDrawable(SkDrawable* drawable, const SkMatrix* matrix) {
	// TODO: investigate culling and applying concat to the matrix
	#if 0
	drawable->draw(this, matrix);
	#else
	this->flush_before_saves();
	fCanvas->drawDrawable(drawable, matrix);
	#endif
	}

	void SkDeferredCanvas::onDrawAtlas(const SkImage* image, const SkRSXform xform[],
	const SkRect rects[], const SkColor colors[],
	int count, SkBlendMode bmode,
	const SkRect* cull, const SkPaint* paint) {
	this->flush_before_saves();
	fCanvas->drawAtlas(image, xform, rects, colors, count, bmode, cull, paint);
	}

	void SkDeferredCanvas::onDrawVertices(VertexMode vmode, int vertexCount,
	const SkPoint vertices[], const SkPoint texs[],
	const SkColor colors[], SkBlendMode bmode,
	const uint16_t indices[], int indexCount,
	const SkPaint& paint) {
	this->flush_before_saves();
	fCanvas->drawVertices(vmode, vertexCount, vertices, texs, colors, bmode,
	indices, indexCount, paint);
	}

	void SkDeferredCanvas::onDrawPatch(const SkPoint cubics[12], const SkColor colors[4],
	const SkPoint texCoords[4], SkBlendMode bmode,
	const SkPaint& paint) {
	this->flush_before_saves();
	fCanvas->drawPatch(cubics, colors, texCoords, bmode, paint);
	}

	void SkDeferredCanvas::onDrawAnnotation(const SkRect& rect, const char key[], SkData* data) {
	SkRect modRect = rect;
	this->flush_check(&modRect, nullptr, kNoClip_Flag);
	fCanvas->drawAnnotation(modRect, key, data);
	}

	#ifdef SK_SUPPORT_LEGACY_DRAWFILTER
	SkDrawFilter* SkDeferredCanvas::setDrawFilter(SkDrawFilter* filter) {
	fCanvas->setDrawFilter(filter);
	return this->INHERITED::setDrawFilter(filter);
	}
	#endif

	///////////////////////////////////////////////////////////////////////////////////////////////////

	sk_sp<SkSurface> SkDeferredCanvas::onNewSurface(const SkImageInfo& info,
	const SkSurfaceProps& props) {
	return fCanvas->makeSurface(info, &props);
	}
	SkISize SkDeferredCanvas::getBaseLayerSize() const { return fCanvas->getBaseLayerSize(); }
	SkRect SkDeferredCanvas::onGetLocalClipBounds() const {
	return fCanvas->getLocalClipBounds();
	}
	SkIRect SkDeferredCanvas::onGetDeviceClipBounds() const {
	return fCanvas->getDeviceClipBounds();
	}
	bool SkDeferredCanvas::isClipEmpty() const { return fCanvas->isClipEmpty(); }
	bool SkDeferredCanvas::isClipRect() const { return fCanvas->isClipRect(); }
	bool SkDeferredCanvas::onPeekPixels(SkPixmap* pixmap) { return fCanvas->peekPixels(pixmap); }
	bool SkDeferredCanvas::onAccessTopLayerPixels(SkPixmap* pixmap) {
	SkImageInfo info;
	size_t rowBytes;
	SkIPoint* origin = nullptr;
	void* addr = fCanvas->accessTopLayerPixels(&info, &rowBytes, origin);
	if (addr) {
	*pixmap = SkPixmap(info, addr, rowBytes);
	return true;
	}
	return false;
	}
	SkImageInfo SkDeferredCanvas::onImageInfo() const { return fCanvas->imageInfo(); }
	bool SkDeferredCanvas::onGetProps(SkSurfaceProps* props) const { return fCanvas->getProps(props); }
	void SkDeferredCanvas::onFlush() {
	this->flush_all();
	return fCanvas->flush();
	}