xref: /external/skqp/include/effects/SkRRectsGaussianEdgeMaskFilter.h

/*
 * Copyright 2016 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#ifndef SkRRectsGaussianEdgeMaskFilter_DEFINED
#define SkRRectsGaussianEdgeMaskFilter_DEFINED

#include "SkMaskFilter.h"
#include "SkScalar.h"

class SkRRect;

class SK_API SkRRectsGaussianEdgeMaskFilter {
public:
    /** Returns a mask filter that applies a Gaussian blur depending on distance to the edge
     *  of the intersection of two round rects.
     *  Currently this is only useable with round rects that have the same radii at
     *  all the corners and for which the x & y radii are equal.
     *
     *  In order to minimize fill the coverage geometry that should be drawn should be no larger
     *  than the intersection of the bounding boxes of the two round rects. Ambitious users can
     *  omit the center area of the coverage geometry if it is known to be occluded.
     */
    static sk_sp<SkMaskFilter> Make(const SkRRect& first,
                                    const SkRRect& second,
                                    SkScalar radius);

    SK_DECLARE_FLATTENABLE_REGISTRAR_GROUP()

private:
    SkRRectsGaussianEdgeMaskFilter(); // can't be instantiated
};

#endif