SkDrawLooper.h

/*
 * Copyright 2011 The Android Open Source Project
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */


#ifndef SkDrawLooper_DEFINED
#define SkDrawLooper_DEFINED

#include "SkBlurTypes.h"
#include "SkFlattenable.h"
#include "SkPoint.h"
#include "SkColor.h"

class  SkArenaAlloc;
class  SkCanvas;
class  SkColorSpaceXformer;
class  SkPaint;
struct SkRect;
class  SkString;

class SK_API SkDrawLooper : public SkFlattenable {
public:
    class SK_API Context : ::SkNoncopyable {
    public:
        Context() {}
        virtual ~Context() {}

        virtual bool next(SkCanvas* canvas, SkPaint* paint) = 0;
    };

    virtual Context* makeContext(SkCanvas*, SkArenaAlloc*) const = 0;

    bool canComputeFastBounds(const SkPaint& paint) const;
    void computeFastBounds(const SkPaint& paint, const SkRect& src, SkRect* dst) const;

    struct BlurShadowRec {
        SkScalar        fSigma;
        SkVector        fOffset;
        SkColor         fColor;
        SkBlurStyle     fStyle;
        SkBlurQuality   fQuality;
    };
    virtual bool asABlurShadow(BlurShadowRec*) const;

    SK_TO_STRING_PUREVIRT()
    SK_DEFINE_FLATTENABLE_TYPE(SkDrawLooper)

protected:
    sk_sp<SkDrawLooper> makeColorSpace(SkColorSpaceXformer* xformer) const {
        return this->onMakeColorSpace(xformer);
    }
    virtual sk_sp<SkDrawLooper> onMakeColorSpace(SkColorSpaceXformer*) const = 0;

    SkDrawLooper() {}

private:
    friend class SkColorSpaceXformer;

    typedef SkFlattenable INHERITED;
};

#endif