include/effects/SkDropShadowImageFilter.h

/*
 * Copyright 2013 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#ifndef SkDropShadowImageFilter_DEFINED
#define SkDropShadowImageFilter_DEFINED

#include "SkColor.h"
#include "SkFlattenable.h"
#include "SkImageFilter.h"
#include "SkScalar.h"

class SK_API SkDropShadowImageFilter : public SkImageFilter {
public:
    enum ShadowMode {
        kDrawShadowAndForeground_ShadowMode,
        kDrawShadowOnly_ShadowMode,

        kLast_ShadowMode = kDrawShadowOnly_ShadowMode
    };

    static const int kShadowModeCount = kLast_ShadowMode+1;

    static sk_sp<SkImageFilter> Make(SkScalar dx, SkScalar dy, SkScalar sigmaX, SkScalar sigmaY,
                                     SkColor color, ShadowMode shadowMode,
                                     sk_sp<SkImageFilter> input,
                                     const CropRect* cropRect = nullptr);

    SkRect computeFastBounds(const SkRect&) const override;

    Factory getFactory() const override { return CreateProc; }

protected:
    void flatten(SkWriteBuffer&) const override;
    sk_sp<SkSpecialImage> onFilterImage(SkSpecialImage* source, const Context&,
                                        SkIPoint* offset) const override;
    sk_sp<SkImageFilter> onMakeColorSpace(SkColorSpaceXformer*) const override;
    SkIRect onFilterNodeBounds(const SkIRect& src, const SkMatrix& ctm,
                               MapDirection, const SkIRect* inputRect) const override;

private:
    SkDropShadowImageFilter(SkScalar dx, SkScalar dy, SkScalar sigmaX, SkScalar sigmaY, SkColor,
                            ShadowMode shadowMode, sk_sp<SkImageFilter> input,
                            const CropRect* cropRect);
    static sk_sp<SkFlattenable> CreateProc(SkReadBuffer&);
    friend class SkFlattenable::PrivateInitializer;

    SkScalar fDx, fDy, fSigmaX, fSigmaY;
    SkColor fColor;
    ShadowMode fShadowMode;

    typedef SkImageFilter INHERITED;
};

#endif