xref: /external/skia/include/effects/SkBlurMaskFilter.h

/*
 * Copyright (C) 2006 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef SkBlurMaskFilter_DEFINED
#define SkBlurMaskFilter_DEFINED

// we include this since our callers will need to at least be able to ref/unref
#include "SkMaskFilter.h"
#include "SkScalar.h"

class SkBlurMaskFilter {
public:
    enum BlurStyle {
        kNormal_BlurStyle,  //!< fuzzy inside and outside
        kSolid_BlurStyle,   //!< solid inside, fuzzy outside
        kOuter_BlurStyle,   //!< nothing inside, fuzzy outside
        kInner_BlurStyle,   //!< fuzzy inside, nothing outside

        kBlurStyleCount
    };

    enum BlurFlags {
        kNone_BlurFlag = 0x00,
        /** The blur layer's radius is not affected by transforms */
        kIgnoreTransform_BlurFlag = 0x01,
        /** mask for all blur flags */
        kAll_BlurFlag = 0x01
    };

    /** Create a blur maskfilter.
        @param radius   The radius to extend the blur from the original mask. Must be > 0.
        @param style    The BlurStyle to use
        @param flags    Flags to use - defaults to none
        @return The new blur maskfilter
    */
    static SkMaskFilter* Create(SkScalar radius, BlurStyle style,
                                uint32_t flags = kNone_BlurFlag);

    /** Create an emboss maskfilter
        @param direction    array of 3 scalars [x, y, z] specifying the direction of the light source
        @param ambient      0...1 amount of ambient light
        @param specular     coefficient for specular highlights (e.g. 8)
        @param blurRadius   amount to blur before applying lighting (e.g. 3)
        @return the emboss maskfilter
    */
    static SkMaskFilter* CreateEmboss(  const SkScalar direction[3],
                                        SkScalar ambient, SkScalar specular,
                                        SkScalar blurRadius);

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

#endif