skia2/include/utils/SkPictureUtils.h
2014-11-19 10:41:14 -08:00

92 lines
2.8 KiB
C++

/*
* Copyright 2012 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkPictureUtils_DEFINED
#define SkPictureUtils_DEFINED
#include "SkPicture.h"
#include "SkTDArray.h"
class SkData;
struct SkRect;
class SK_API SkPictureUtils {
public:
/**
* Given a rectangular visible "window" into the picture, return an array
* of SkPixelRefs that might intersect that area. To keep the call fast,
* the returned list is not guaranteed to be exact, so it may miss some,
* and it may return false positives.
*
* The pixelrefs returned in the SkData are already owned by the picture,
* so the returned pointers are only valid while the picture is in scope
* and remains unchanged.
*/
static SkData* GatherPixelRefs(const SkPicture* pict, const SkRect& area);
/**
* SkPixelRefContainer provides a base class for more elaborate pixel ref
* query structures (e.g., rtrees, quad-trees, etc.)
*/
class SkPixelRefContainer : public SkRefCnt {
public:
virtual void add(SkPixelRef* pr, const SkRect& rect) = 0;
// The returned array may contain duplicates
virtual void query(const SkRect& queryRect, SkTDArray<SkPixelRef*> *result) = 0;
private:
typedef SkRefCnt INHERITED;
};
// Simple query structure that just stores a linked list of pixel refs
// and rects.
class SkPixelRefsAndRectsList : public SkPixelRefContainer {
public:
virtual void add(SkPixelRef* pr, const SkRect& rect) SK_OVERRIDE {
PixelRefAndRect *dst = fArray.append();
dst->fPixelRef = pr;
dst->fRect = rect;
}
virtual void query(const SkRect& queryRect, SkTDArray<SkPixelRef*> *result) SK_OVERRIDE {
for (int i = 0; i < fArray.count(); ++i) {
if (SkRect::Intersects(fArray[i].fRect, queryRect)) {
*result->append() = fArray[i].fPixelRef;
}
}
}
private:
struct PixelRefAndRect {
SkPixelRef* fPixelRef;
SkRect fRect;
};
SkTDArray<PixelRefAndRect> fArray;
typedef SkPixelRefContainer INHERITED;
};
/**
* Fill the provided pixel ref container with the picture's pixel ref
* and rect information.
*/
static void GatherPixelRefsAndRects(SkPicture* pict, SkPixelRefContainer* prCont);
/**
* How many bytes are allocated to hold the SkPicture.
* Includes operations, parameters, bounding data, deletion listeners;
* includes nested SkPictures, but does not include large objects that
* SkRecord holds a reference to (e.g. paths, or pixels backing bitmaps).
*/
static size_t ApproximateBytesUsed(const SkPicture* pict);
};
#endif