include/core/SkDrawFilter.h

/*
 * Copyright (C) 2011 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 SkDrawFilter_DEFINED
#define SkDrawFilter_DEFINED

#include "SkRefCnt.h"

class SkCanvas;
class SkPaint;

/**
 *  Right before something is being draw, filter() is called with the
 *  paint. The filter may modify the paint as it wishes, which will then be
 *  used for the actual drawing. Note: this modification only lasts for the
 *  current draw, as a temporary copy of the paint is used.
 */
class SkDrawFilter : public SkRefCnt {
public:
    enum Type {
        kPaint_Type,
        kPoint_Type,
        kLine_Type,
        kBitmap_Type,
        kRect_Type,
        kPath_Type,
        kText_Type
    };

    /**
     *  Called with the paint that will be used to draw the specified type.
     *  The implementation may modify the paint as they wish.
     */
    virtual void filter(SkPaint*, Type) = 0;
};

#endif