SkCanvas::resetForNextPicture()

src/core/SkCanvas.cpp

 /*
  * Copyright 2008 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkCanvas.h"
 #include "SkCanvasPriv.h"
 #include "SkBitmapDevice.h"
@@ skipping 117 matching lines @@
     }
 
     ~DeviceCM() {
         if (fDevice) {
             fDevice->onDetachFromCanvas();
             fDevice->unref();
         }
         SkDELETE(fPaint);
     }
 
+    void reset(const SkIRect& bounds) {
+        SkASSERT(!fPaint);
+        SkASSERT(!fNext);
+        SkASSERT(fDevice);
+        fClip.setRect(bounds);
+    }
+
     void updateMC(const SkMatrix& totalMatrix, const SkRasterClip& totalClip,
                   const SkClipStack& clipStack, SkRasterClip* updateClip) {
         int x = fDevice->getOrigin().x();
         int y = fDevice->getOrigin().y();
         int width = fDevice->width();
         int height = fDevice->height();
 
         if ((x | y) == 0) {
             fMatrix = &totalMatrix;
             fClip = totalClip;
@@ skipping 69 matching lines @@
         fDeferredSaveCount = 0;
 
         // don't bother initializing fNext
         inc_rec();
     }
     ~MCRec() {
         SkSafeUnref(fFilter);
         SkDELETE(fLayer);
         dec_rec();
     }
+
+    void reset(const SkIRect& bounds) {
+        SkASSERT(fLayer);
+        SkASSERT(fDeferredSaveCount == 0);
+
+        fMatrix.reset();
+        fRasterClip.setRect(bounds);
+        fLayer->reset(bounds);
+    }
 };
 
 class SkDrawIter : public SkDraw {
 public:
     SkDrawIter(SkCanvas* canvas, bool skipEmptyClips = true) {
         canvas = canvas->canvasForDrawIter();
         fCanvas = canvas;
         canvas->updateDeviceCMCache();
 
         fClipStack = canvas->fClipStack;
@@ skipping 181 matching lines @@
 #define LOOPER_BEGIN(paint, type, bounds)                           \
     this->predrawNotify();                                          \
     AutoDrawLooper  looper(this, fProps, paint, false, bounds);     \
     while (looper.next(type)) {                                     \
         SkDrawIter          iter(this);
 
 #define LOOPER_END    }
 
 ////////////////////////////////////////////////////////////////////////////
 
+void SkCanvas::resetForNextPicture(const SkIRect& bounds) {
+    this->restoreToCount(1);
+    fCachedLocalClipBounds.setEmpty();
+    fCachedLocalClipBoundsDirty = true;
+    fClipStack->reset();
+    fMCRec->reset(bounds);
+
+    // We're peering through a lot of structs here.  Only at this scope do we
+    // know that the device is an SkBitmapDevice (really an SkNoPixelsBitmapDevice).
+    static_cast<SkBitmapDevice*>(fMCRec->fLayer->fDevice)->setNewSize(bounds.size());
+}
+
 SkBaseDevice* SkCanvas::init(SkBaseDevice* device, InitFlags flags) {
     fConservativeRasterClip = SkToBool(flags & kConservativeRasterClip_InitFlag);
     fCachedLocalClipBounds.setEmpty();
     fCachedLocalClipBoundsDirty = true;
     fAllowSoftClip = true;
     fAllowSimplifyClip = false;
     fDeviceCMDirty = true;
     fSaveCount = 1;
     fMetaData = NULL;
 
@@ skipping 2081 matching lines @@
     }
 
     if (matrix) {
         canvas->concat(*matrix);
     }
 }
 
 SkAutoCanvasMatrixPaint::~SkAutoCanvasMatrixPaint() {
     fCanvas->restoreToCount(fSaveCount);
 }