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 "SkBitmapDevice.h"
michael@0: #include "SkCanvas.h"
michael@0: #include "SkData.h"
michael@0: #include "SkNoSaveLayerCanvas.h"
michael@0: #include "SkPictureUtils.h"
michael@0: #include "SkPixelRef.h"
michael@0: #include "SkRRect.h"
michael@0: #include "SkShader.h"
michael@0: 
michael@0: class PixelRefSet {
michael@0: public:
michael@0:     PixelRefSet(SkTDArray<SkPixelRef*>* array) : fArray(array) {}
michael@0: 
michael@0:     // This does a linear search on existing pixelrefs, so if this list gets big
michael@0:     // we should use a more complex sorted/hashy thing.
michael@0:     //
michael@0:     void add(SkPixelRef* pr) {
michael@0:         uint32_t genID = pr->getGenerationID();
michael@0:         if (fGenID.find(genID) < 0) {
michael@0:             *fArray->append() = pr;
michael@0:             *fGenID.append() = genID;
michael@0: //            SkDebugf("--- adding [%d] %x %d\n", fArray->count() - 1, pr, genID);
michael@0:         } else {
michael@0: //            SkDebugf("--- already have %x %d\n", pr, genID);
michael@0:         }
michael@0:     }
michael@0: 
michael@0: private:
michael@0:     SkTDArray<SkPixelRef*>* fArray;
michael@0:     SkTDArray<uint32_t>     fGenID;
michael@0: };
michael@0: 
michael@0: static void not_supported() {
michael@0:     SkDEBUGFAIL("this method should never be called");
michael@0: }
michael@0: 
michael@0: static void nothing_to_do() {}
michael@0: 
michael@0: /**
michael@0:  *  This device will route all bitmaps (primitives and in shaders) to its PRSet.
michael@0:  *  It should never actually draw anything, so there need not be any pixels
michael@0:  *  behind its device.
michael@0:  */
michael@0: class GatherPixelRefDevice : public SkBaseDevice {
michael@0: public:
michael@0:     SK_DECLARE_INST_COUNT(GatherPixelRefDevice)
michael@0: 
michael@0:     GatherPixelRefDevice(int width, int height, PixelRefSet* prset) {
michael@0:         fSize.set(width, height);
michael@0:         fEmptyBitmap.setConfig(SkImageInfo::MakeUnknown(width, height));
michael@0:         fPRSet = prset;
michael@0:     }
michael@0: 
michael@0:     virtual int width() const SK_OVERRIDE { return fSize.width(); }
michael@0:     virtual int height() const SK_OVERRIDE { return fSize.height(); }
michael@0:     virtual bool isOpaque() const SK_OVERRIDE { return false; }
michael@0:     virtual SkBitmap::Config config() const SK_OVERRIDE {
michael@0:         return SkBitmap::kNo_Config;
michael@0:     }
michael@0:     virtual GrRenderTarget* accessRenderTarget() SK_OVERRIDE { return NULL; }
michael@0:     virtual bool filterTextFlags(const SkPaint& paint, TextFlags*) SK_OVERRIDE {
michael@0:         return false;
michael@0:     }
michael@0:     // TODO: allow this call to return failure, or move to SkBitmapDevice only.
michael@0:     virtual const SkBitmap& onAccessBitmap() SK_OVERRIDE {
michael@0:         return fEmptyBitmap;
michael@0:     }
michael@0:     virtual void lockPixels() SK_OVERRIDE { nothing_to_do(); }
michael@0:     virtual void unlockPixels() SK_OVERRIDE { nothing_to_do(); }
michael@0:     virtual bool allowImageFilter(const SkImageFilter*) SK_OVERRIDE { return false; }
michael@0:     virtual bool canHandleImageFilter(const SkImageFilter*) SK_OVERRIDE { return false; }
michael@0:     virtual bool filterImage(const SkImageFilter*, const SkBitmap&, const SkImageFilter::Context&,
michael@0:                              SkBitmap* result, SkIPoint* offset) SK_OVERRIDE {
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     virtual void clear(SkColor color) SK_OVERRIDE {
michael@0:         nothing_to_do();
michael@0:     }
michael@0: 
michael@0: #ifdef SK_SUPPORT_LEGACY_WRITEPIXELSCONFIG
michael@0:     virtual void writePixels(const SkBitmap& bitmap, int x, int y,
michael@0:                              SkCanvas::Config8888 config8888) SK_OVERRIDE {
michael@0:         not_supported();
michael@0:     }
michael@0: #endif
michael@0: 
michael@0:     virtual void drawPaint(const SkDraw&, const SkPaint& paint) SK_OVERRIDE {
michael@0:         this->addBitmapFromPaint(paint);
michael@0:     }
michael@0:     virtual void drawPoints(const SkDraw&, SkCanvas::PointMode mode, size_t count,
michael@0:                             const SkPoint[], const SkPaint& paint) SK_OVERRIDE {
michael@0:         this->addBitmapFromPaint(paint);
michael@0:     }
michael@0:     virtual void drawRect(const SkDraw&, const SkRect&,
michael@0:                           const SkPaint& paint) SK_OVERRIDE {
michael@0:         this->addBitmapFromPaint(paint);
michael@0:     }
michael@0:     virtual void drawRRect(const SkDraw&, const SkRRect&,
michael@0:                            const SkPaint& paint) SK_OVERRIDE {
michael@0:         this->addBitmapFromPaint(paint);
michael@0:     }
michael@0:     virtual void drawOval(const SkDraw&, const SkRect&,
michael@0:                           const SkPaint& paint) SK_OVERRIDE {
michael@0:         this->addBitmapFromPaint(paint);
michael@0:     }
michael@0:     virtual void drawPath(const SkDraw&, const SkPath& path,
michael@0:                           const SkPaint& paint, const SkMatrix* prePathMatrix,
michael@0:                           bool pathIsMutable) SK_OVERRIDE {
michael@0:         this->addBitmapFromPaint(paint);
michael@0:     }
michael@0:     virtual void drawBitmap(const SkDraw&, const SkBitmap& bitmap,
michael@0:                             const SkMatrix&, const SkPaint& paint) SK_OVERRIDE {
michael@0:         this->addBitmap(bitmap);
michael@0:         if (SkBitmap::kA8_Config == bitmap.config()) {
michael@0:             this->addBitmapFromPaint(paint);
michael@0:         }
michael@0:     }
michael@0:     virtual void drawBitmapRect(const SkDraw&, const SkBitmap& bitmap,
michael@0:                                 const SkRect* srcOrNull, const SkRect& dst,
michael@0:                                 const SkPaint& paint,
michael@0:                                 SkCanvas::DrawBitmapRectFlags flags) SK_OVERRIDE {
michael@0:         this->addBitmap(bitmap);
michael@0:         if (SkBitmap::kA8_Config == bitmap.config()) {
michael@0:             this->addBitmapFromPaint(paint);
michael@0:         }
michael@0:     }
michael@0:     virtual void drawSprite(const SkDraw&, const SkBitmap& bitmap,
michael@0:                             int x, int y, const SkPaint& paint) SK_OVERRIDE {
michael@0:         this->addBitmap(bitmap);
michael@0:     }
michael@0:     virtual void drawText(const SkDraw&, const void* text, size_t len,
michael@0:                           SkScalar x, SkScalar y,
michael@0:                           const SkPaint& paint) SK_OVERRIDE {
michael@0:         this->addBitmapFromPaint(paint);
michael@0:     }
michael@0:     virtual void drawPosText(const SkDraw&, const void* text, size_t len,
michael@0:                              const SkScalar pos[], SkScalar constY,
michael@0:                              int, const SkPaint& paint) SK_OVERRIDE {
michael@0:         this->addBitmapFromPaint(paint);
michael@0:     }
michael@0:     virtual void drawTextOnPath(const SkDraw&, const void* text, size_t len,
michael@0:                                 const SkPath& path, const SkMatrix* matrix,
michael@0:                                 const SkPaint& paint) SK_OVERRIDE {
michael@0:         this->addBitmapFromPaint(paint);
michael@0:     }
michael@0:     virtual void drawVertices(const SkDraw&, SkCanvas::VertexMode, int vertexCount,
michael@0:                               const SkPoint verts[], const SkPoint texs[],
michael@0:                               const SkColor colors[], SkXfermode* xmode,
michael@0:                               const uint16_t indices[], int indexCount,
michael@0:                               const SkPaint& paint) SK_OVERRIDE {
michael@0:         this->addBitmapFromPaint(paint);
michael@0:     }
michael@0:     virtual void drawDevice(const SkDraw&, SkBaseDevice*, int x, int y,
michael@0:                             const SkPaint&) SK_OVERRIDE {
michael@0:         nothing_to_do();
michael@0:     }
michael@0: 
michael@0: protected:
michael@0:     virtual bool onReadPixels(const SkBitmap& bitmap,
michael@0:                               int x, int y,
michael@0:                               SkCanvas::Config8888 config8888) SK_OVERRIDE {
michael@0:         not_supported();
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     virtual void replaceBitmapBackendForRasterSurface(const SkBitmap&) SK_OVERRIDE {
michael@0:         not_supported();
michael@0:     }
michael@0:     virtual SkBaseDevice* onCreateDevice(const SkImageInfo& info, Usage usage) SK_OVERRIDE {
michael@0:         // we expect to only get called via savelayer, in which case it is fine.
michael@0:         SkASSERT(kSaveLayer_Usage == usage);
michael@0:         return SkNEW_ARGS(GatherPixelRefDevice, (info.width(), info.height(), fPRSet));
michael@0:     }
michael@0:     virtual void flush() SK_OVERRIDE {}
michael@0: 
michael@0: private:
michael@0:     PixelRefSet*  fPRSet;
michael@0:     SkBitmap fEmptyBitmap;  // legacy -- need to remove the need for this guy
michael@0:     SkISize fSize;
michael@0: 
michael@0:     void addBitmap(const SkBitmap& bm) {
michael@0:       fPRSet->add(bm.pixelRef());
michael@0:     }
michael@0: 
michael@0:     void addBitmapFromPaint(const SkPaint& paint) {
michael@0:       SkShader* shader = paint.getShader();
michael@0:       if (shader) {
michael@0:           SkBitmap bm;
michael@0:           // Check whether the shader is a gradient in order to short-circuit
michael@0:           // call to asABitmap to prevent generation of bitmaps from
michael@0:           // gradient shaders, which implement asABitmap.
michael@0:           if (SkShader::kNone_GradientType == shader->asAGradient(NULL) &&
michael@0:               shader->asABitmap(&bm, NULL, NULL)) {
michael@0:               fPRSet->add(bm.pixelRef());
michael@0:           }
michael@0:       }
michael@0:     }
michael@0: 
michael@0:     typedef SkBaseDevice INHERITED;
michael@0: };
michael@0: 
michael@0: SkData* SkPictureUtils::GatherPixelRefs(SkPicture* pict, const SkRect& area) {
michael@0:     if (NULL == pict) {
michael@0:         return NULL;
michael@0:     }
michael@0: 
michael@0:     // this test also handles if either area or pict's width/height are empty
michael@0:     if (!SkRect::Intersects(area,
michael@0:                             SkRect::MakeWH(SkIntToScalar(pict->width()),
michael@0:                                            SkIntToScalar(pict->height())))) {
michael@0:         return NULL;
michael@0:     }
michael@0: 
michael@0:     SkTDArray<SkPixelRef*> array;
michael@0:     PixelRefSet prset(&array);
michael@0: 
michael@0:     GatherPixelRefDevice device(pict->width(), pict->height(), &prset);
michael@0:     SkNoSaveLayerCanvas canvas(&device);
michael@0: 
michael@0:     canvas.clipRect(area, SkRegion::kIntersect_Op, false);
michael@0:     canvas.drawPicture(*pict);
michael@0: 
michael@0:     SkData* data = NULL;
michael@0:     int count = array.count();
michael@0:     if (count > 0) {
michael@0:         data = SkData::NewFromMalloc(array.detach(), count * sizeof(SkPixelRef*));
michael@0:     }
michael@0:     return data;
michael@0: }