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: #ifndef SkPictureUtils_DEFINED
michael@0: #define SkPictureUtils_DEFINED
michael@0: 
michael@0: #include "SkPicture.h"
michael@0: #include "SkTDArray.h"
michael@0: 
michael@0: class SkData;
michael@0: struct SkRect;
michael@0: 
michael@0: class SK_API SkPictureUtils {
michael@0: public:
michael@0:     /**
michael@0:      *  Given a rectangular visible "window" into the picture, return an array
michael@0:      *  of SkPixelRefs that might intersect that area. To keep the call fast,
michael@0:      *  the returned list is not guaranteed to be exact, so it may miss some,
michael@0:      *  and it may return false positives.
michael@0:      *
michael@0:      *  The pixelrefs returned in the SkData are already owned by the picture,
michael@0:      *  so the returned pointers are only valid while the picture is in scope
michael@0:      *  and remains unchanged.
michael@0:      */
michael@0:     static SkData* GatherPixelRefs(SkPicture* pict, const SkRect& area);
michael@0: 
michael@0:     /**
michael@0:      * SkPixelRefContainer provides a base class for more elaborate pixel ref
michael@0:      * query structures (e.g., rtrees, quad-trees, etc.)
michael@0:      */
michael@0:     class SkPixelRefContainer : public SkRefCnt {
michael@0:     public:
michael@0:         virtual void add(SkPixelRef* pr, const SkRect& rect) = 0;
michael@0: 
michael@0:         // The returned array may contain duplicates
michael@0:         virtual void query(const SkRect& queryRect, SkTDArray<SkPixelRef*> *result) = 0;
michael@0: 
michael@0:     private:
michael@0:         typedef SkRefCnt INHERITED;
michael@0:     };
michael@0: 
michael@0:     // Simple query structure that just stores a linked list of pixel refs
michael@0:     // and rects.
michael@0:     class SkPixelRefsAndRectsList : public SkPixelRefContainer {
michael@0:     public:
michael@0:         virtual void add(SkPixelRef* pr, const SkRect& rect) SK_OVERRIDE {
michael@0:             PixelRefAndRect *dst = fArray.append();
michael@0: 
michael@0:             dst->fPixelRef = pr;
michael@0:             dst->fRect = rect;
michael@0:         }
michael@0: 
michael@0:         virtual void query(const SkRect& queryRect, SkTDArray<SkPixelRef*> *result) SK_OVERRIDE {
michael@0:             for (int i = 0; i < fArray.count(); ++i) {
michael@0:                 if (SkRect::Intersects(fArray[i].fRect, queryRect)) {
michael@0:                     *result->append() = fArray[i].fPixelRef;
michael@0:                 }
michael@0:             }
michael@0:         }
michael@0: 
michael@0:     private:
michael@0:         struct PixelRefAndRect {
michael@0:             SkPixelRef* fPixelRef;
michael@0:             SkRect      fRect;
michael@0:         };
michael@0: 
michael@0:         SkTDArray<PixelRefAndRect> fArray;
michael@0: 
michael@0:         typedef SkPixelRefContainer INHERITED;
michael@0:     };
michael@0: 
michael@0:     /**
michael@0:      *  Fill the provided pixel ref container with the picture's pixel ref
michael@0:      *  and rect information.
michael@0:      */
michael@0:     static void GatherPixelRefsAndRects(SkPicture* pict, SkPixelRefContainer* prCont);
michael@0: };
michael@0: 
michael@0: #endif