/*
* Copyright 2012 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkPictureUtils.h"
#include "SkCanvas.h"
#include "SkData.h"
#include "SkDevice.h"
#include "SkPixelRef.h"
#include "SkShader.h"
#include "SkRRect.h"
class PixelRefSet {
public:
PixelRefSet(SkTDArray<SkPixelRef*>* array) : fArray(array) {}
// This does a linear search on existing pixelrefs, so if this list gets big
// we should use a more complex sorted/hashy thing.
//
void add(SkPixelRef* pr) {
uint32_t genID = pr->getGenerationID();
if (fGenID.find(genID) < 0) {
*fArray->append() = pr;
*fGenID.append() = genID;
// SkDebugf("--- adding [%d] %x %d\n", fArray->count() - 1, pr, genID);
} else {
// SkDebugf("--- already have %x %d\n", pr, genID);
}
}
private:
SkTDArray<SkPixelRef*>* fArray;
SkTDArray<uint32_t> fGenID;
};
static void not_supported() {
SkASSERT(!"this method should never be called");
}
static void nothing_to_do() {}
/**
* This device will route all bitmaps (primitives and in shaders) to its PRSet.
* It should never actually draw anything, so there need not be any pixels
* behind its device-bitmap.
*/
class GatherPixelRefDevice : public SkDevice {
private:
PixelRefSet* fPRSet;
void addBitmap(const SkBitmap& bm) {
fPRSet->add(bm.pixelRef());
}
void addBitmapFromPaint(const SkPaint& paint) {
SkShader* shader = paint.getShader();
if (shader) {
SkBitmap bm;
// Check whether the shader is a gradient in order to short-circuit
// call to asABitmap to prevent generation of bitmaps from
// gradient shaders, which implement asABitmap.
if (SkShader::kNone_GradientType == shader->asAGradient(NULL) &&
shader->asABitmap(&bm, NULL, NULL)) {
fPRSet->add(bm.pixelRef());
}
}
}
public:
GatherPixelRefDevice(const SkBitmap& bm, PixelRefSet* prset) : SkDevice(bm) {
fPRSet = prset;
}
virtual void clear(SkColor color) SK_OVERRIDE {
nothing_to_do();
}
virtual void writePixels(const SkBitmap& bitmap, int x, int y,
SkCanvas::Config8888 config8888) SK_OVERRIDE {
not_supported();
}
virtual void drawPaint(const SkDraw&, const SkPaint& paint) SK_OVERRIDE {
this->addBitmapFromPaint(paint);
}
virtual void drawPoints(const SkDraw&, SkCanvas::PointMode mode, size_t count,
const SkPoint[], const SkPaint& paint) SK_OVERRIDE {
this->addBitmapFromPaint(paint);
}
virtual void drawRect(const SkDraw&, const SkRect&,
const SkPaint& paint) SK_OVERRIDE {
this->addBitmapFromPaint(paint);
}
virtual void drawOval(const SkDraw&, const SkRect&,
const SkPaint& paint) SK_OVERRIDE {
this->addBitmapFromPaint(paint);
}
virtual void drawPath(const SkDraw&, const SkPath& path,
const SkPaint& paint, const SkMatrix* prePathMatrix,
bool pathIsMutable) SK_OVERRIDE {
this->addBitmapFromPaint(paint);
}
virtual void drawBitmap(const SkDraw&, const SkBitmap& bitmap,
const SkIRect* srcRectOrNull,
const SkMatrix&, const SkPaint&) SK_OVERRIDE {
this->addBitmap(bitmap);
}
virtual void drawBitmapRect(const SkDraw&, const SkBitmap& bitmap,
const SkRect* srcOrNull, const SkRect& dst,
const SkPaint&) SK_OVERRIDE {
this->addBitmap(bitmap);
}
virtual void drawSprite(const SkDraw&, const SkBitmap& bitmap,
int x, int y, const SkPaint& paint) SK_OVERRIDE {
this->addBitmap(bitmap);
}
virtual void drawText(const SkDraw&, const void* text, size_t len,
SkScalar x, SkScalar y,
const SkPaint& paint) SK_OVERRIDE {
this->addBitmapFromPaint(paint);
}
virtual void drawPosText(const SkDraw&, const void* text, size_t len,
const SkScalar pos[], SkScalar constY,
int, const SkPaint& paint) SK_OVERRIDE {
this->addBitmapFromPaint(paint);
}
virtual void drawTextOnPath(const SkDraw&, const void* text, size_t len,
const SkPath& path, const SkMatrix* matrix,
const SkPaint& paint) SK_OVERRIDE {
this->addBitmapFromPaint(paint);
}
virtual void drawVertices(const SkDraw&, SkCanvas::VertexMode, int vertexCount,
const SkPoint verts[], const SkPoint texs[],
const SkColor colors[], SkXfermode* xmode,
const uint16_t indices[], int indexCount,
const SkPaint& paint) SK_OVERRIDE {
this->addBitmapFromPaint(paint);
}
virtual void drawDevice(const SkDraw&, SkDevice*, int x, int y,
const SkPaint&) SK_OVERRIDE {
nothing_to_do();
}
protected:
virtual bool onReadPixels(const SkBitmap& bitmap,
int x, int y,
SkCanvas::Config8888 config8888) SK_OVERRIDE {
not_supported();
return false;
}
};
class NoSaveLayerCanvas : public SkCanvas {
public:
NoSaveLayerCanvas(SkDevice* device) : INHERITED(device) {}
// turn saveLayer() into save() for speed, should not affect correctness.
virtual int saveLayer(const SkRect* bounds, const SkPaint* paint,
SaveFlags flags) SK_OVERRIDE {
// Like SkPictureRecord, we don't want to create layers, but we do need
// to respect the save and (possibly) its rect-clip.
int count = this->INHERITED::save(flags);
if (bounds) {
this->INHERITED::clipRectBounds(bounds, flags, NULL);
}
return count;
}
// disable aa for speed
virtual bool clipRect(const SkRect& rect, SkRegion::Op op,
bool doAA) SK_OVERRIDE {
return this->INHERITED::clipRect(rect, op, false);
}
// for speed, just respect the bounds, and disable AA. May give us a few
// false positives and negatives.
virtual bool clipPath(const SkPath& path, SkRegion::Op op,
bool doAA) SK_OVERRIDE {
return this->INHERITED::clipRect(path.getBounds(), op, false);
}
virtual bool clipRRect(const SkRRect& rrect, SkRegion::Op op,
bool doAA) SK_OVERRIDE {
return this->INHERITED::clipRect(rrect.getBounds(), op, false);
}
private:
typedef SkCanvas INHERITED;
};
SkData* SkPictureUtils::GatherPixelRefs(SkPicture* pict, const SkRect& area) {
if (NULL == pict) {
return NULL;
}
// this test also handles if either area or pict's width/height are empty
if (!SkRect::Intersects(area,
SkRect::MakeWH(SkIntToScalar(pict->width()),
SkIntToScalar(pict->height())))) {
return NULL;
}
SkTDArray<SkPixelRef*> array;
PixelRefSet prset(&array);
SkBitmap emptyBitmap;
emptyBitmap.setConfig(SkBitmap::kARGB_8888_Config, pict->width(), pict->height());
// note: we do not set any pixels (shouldn't need to)
GatherPixelRefDevice device(emptyBitmap, &prset);
NoSaveLayerCanvas canvas(&device);
canvas.clipRect(area, SkRegion::kIntersect_Op, false);
canvas.drawPicture(*pict);
SkData* data = NULL;
int count = array.count();
if (count > 0) {
data = SkData::NewFromMalloc(array.detach(), count * sizeof(SkPixelRef*));
}
return data;
}