michael@0: /*
michael@0:  * Copyright 2012 Google Inc.
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: 
michael@0: #include "SkSurface_Base.h"
michael@0: #include "SkImagePriv.h"
michael@0: #include "SkCanvas.h"
michael@0: #include "SkDevice.h"
michael@0: #include "SkMallocPixelRef.h"
michael@0: 
michael@0: static const size_t kIgnoreRowBytesValue = (size_t)~0;
michael@0: 
michael@0: class SkSurface_Raster : public SkSurface_Base {
michael@0: public:
michael@0:     static bool Valid(const SkImageInfo&, size_t rb = kIgnoreRowBytesValue);
michael@0: 
michael@0:     SkSurface_Raster(const SkImageInfo&, void*, size_t rb);
michael@0:     SkSurface_Raster(SkPixelRef*);
michael@0: 
michael@0:     virtual SkCanvas* onNewCanvas() SK_OVERRIDE;
michael@0:     virtual SkSurface* onNewSurface(const SkImageInfo&) SK_OVERRIDE;
michael@0:     virtual SkImage* onNewImageSnapshot() SK_OVERRIDE;
michael@0:     virtual void onDraw(SkCanvas*, SkScalar x, SkScalar y,
michael@0:                         const SkPaint*) SK_OVERRIDE;
michael@0:     virtual void onCopyOnWrite(ContentChangeMode) SK_OVERRIDE;
michael@0: 
michael@0: private:
michael@0:     SkBitmap    fBitmap;
michael@0:     bool        fWeOwnThePixels;
michael@0: 
michael@0:     typedef SkSurface_Base INHERITED;
michael@0: };
michael@0: 
michael@0: ///////////////////////////////////////////////////////////////////////////////
michael@0: 
michael@0: bool SkSurface_Raster::Valid(const SkImageInfo& info, size_t rowBytes) {
michael@0:     static const size_t kMaxTotalSize = SK_MaxS32;
michael@0: 
michael@0:     int shift = 0;
michael@0:     switch (info.fColorType) {
michael@0:         case kAlpha_8_SkColorType:
michael@0:             shift = 0;
michael@0:             break;
michael@0:         case kRGB_565_SkColorType:
michael@0:             shift = 1;
michael@0:             break;
michael@0:         case kPMColor_SkColorType:
michael@0:             shift = 2;
michael@0:             break;
michael@0:         default:
michael@0:             return false;
michael@0:     }
michael@0: 
michael@0:     if (kIgnoreRowBytesValue == rowBytes) {
michael@0:         return true;
michael@0:     }
michael@0: 
michael@0:     uint64_t minRB = (uint64_t)info.fWidth << shift;
michael@0:     if (minRB > rowBytes) {
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     size_t alignedRowBytes = rowBytes >> shift << shift;
michael@0:     if (alignedRowBytes != rowBytes) {
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     uint64_t size = sk_64_mul(info.fHeight, rowBytes);
michael@0:     if (size > kMaxTotalSize) {
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: SkSurface_Raster::SkSurface_Raster(const SkImageInfo& info, void* pixels, size_t rb)
michael@0:     : INHERITED(info)
michael@0: {
michael@0:     fBitmap.setConfig(info, rb);
michael@0:     fBitmap.setPixels(pixels);
michael@0:     fWeOwnThePixels = false;    // We are "Direct"
michael@0: }
michael@0: 
michael@0: SkSurface_Raster::SkSurface_Raster(SkPixelRef* pr)
michael@0:     : INHERITED(pr->info().fWidth, pr->info().fHeight)
michael@0: {
michael@0:     const SkImageInfo& info = pr->info();
michael@0: 
michael@0:     fBitmap.setConfig(info, info.minRowBytes());
michael@0:     fBitmap.setPixelRef(pr);
michael@0:     fWeOwnThePixels = true;
michael@0: 
michael@0:     if (!info.isOpaque()) {
michael@0:         fBitmap.eraseColor(SK_ColorTRANSPARENT);
michael@0:     }
michael@0: }
michael@0: 
michael@0: SkCanvas* SkSurface_Raster::onNewCanvas() {
michael@0:     return SkNEW_ARGS(SkCanvas, (fBitmap));
michael@0: }
michael@0: 
michael@0: SkSurface* SkSurface_Raster::onNewSurface(const SkImageInfo& info) {
michael@0:     return SkSurface::NewRaster(info);
michael@0: }
michael@0: 
michael@0: void SkSurface_Raster::onDraw(SkCanvas* canvas, SkScalar x, SkScalar y,
michael@0:                               const SkPaint* paint) {
michael@0:     canvas->drawBitmap(fBitmap, x, y, paint);
michael@0: }
michael@0: 
michael@0: SkImage* SkSurface_Raster::onNewImageSnapshot() {
michael@0:     return SkNewImageFromBitmap(fBitmap, fWeOwnThePixels);
michael@0: }
michael@0: 
michael@0: void SkSurface_Raster::onCopyOnWrite(ContentChangeMode mode) {
michael@0:     // are we sharing pixelrefs with the image?
michael@0:     SkASSERT(NULL != this->getCachedImage());
michael@0:     if (SkBitmapImageGetPixelRef(this->getCachedImage()) == fBitmap.pixelRef()) {
michael@0:         SkASSERT(fWeOwnThePixels);
michael@0:         if (kDiscard_ContentChangeMode == mode) {
michael@0:             fBitmap.setPixelRef(NULL);
michael@0:             fBitmap.allocPixels();
michael@0:         } else {
michael@0:             SkBitmap prev(fBitmap);
michael@0:             prev.deepCopyTo(&fBitmap);
michael@0:         }
michael@0:         // Now fBitmap is a deep copy of itself (and therefore different from
michael@0:         // what is being used by the image. Next we update the canvas to use
michael@0:         // this as its backend, so we can't modify the image's pixels anymore.
michael@0:         SkASSERT(NULL != this->getCachedCanvas());
michael@0:         this->getCachedCanvas()->getDevice()->replaceBitmapBackendForRasterSurface(fBitmap);
michael@0:     }
michael@0: }
michael@0: 
michael@0: ///////////////////////////////////////////////////////////////////////////////
michael@0: 
michael@0: SkSurface* SkSurface::NewRasterDirect(const SkImageInfo& info, void* pixels, size_t rowBytes) {
michael@0:     if (!SkSurface_Raster::Valid(info, rowBytes)) {
michael@0:         return NULL;
michael@0:     }
michael@0:     if (NULL == pixels) {
michael@0:         return NULL;
michael@0:     }
michael@0: 
michael@0:     return SkNEW_ARGS(SkSurface_Raster, (info, pixels, rowBytes));
michael@0: }
michael@0: 
michael@0: SkSurface* SkSurface::NewRaster(const SkImageInfo& info) {
michael@0:     if (!SkSurface_Raster::Valid(info)) {
michael@0:         return NULL;
michael@0:     }
michael@0: 
michael@0:     SkAutoTUnref<SkPixelRef> pr(SkMallocPixelRef::NewAllocate(info, 0, NULL));
michael@0:     if (NULL == pr.get()) {
michael@0:         return NULL;
michael@0:     }
michael@0:     return SkNEW_ARGS(SkSurface_Raster, (pr));
michael@0: }