SkTransparentShader.h revision 8a1c16ff38322f0210116fa7293eb8817c7e477e 
1/*
2 * Copyright (C) 2006 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef SkTransparentShader_DEFINED
18#define SkTransparentShader_DEFINED
19
20#include "SkShader.h"
21
22class SkTransparentShader : public SkShader {
23public:
24    SkTransparentShader() {}
25    virtual uint32_t getFlags();
26    virtual bool    setContext( const SkBitmap& device,
27                                const SkPaint& paint,
28                                const SkMatrix& matrix);
29    virtual void    shadeSpan(int x, int y, SkPMColor[], int count);
30    virtual void    shadeSpan16(int x, int y, uint16_t span[], int count);
31
32    // overrides for SkFlattenable
33    virtual Factory getFactory() { return Create; }
34    virtual void flatten(SkFlattenableWriteBuffer& buffer)
35    {
36        this->INHERITED::flatten(buffer);
37    }
38
39private:
40    // these are a cache from the call to setContext()
41    const SkBitmap* fDevice;
42    uint8_t         fAlpha;
43
44    SkTransparentShader(SkFlattenableReadBuffer& buffer) : INHERITED(buffer) {}
45
46    static SkFlattenable* Create(SkFlattenableReadBuffer& buffer)
47    {
48        return SkNEW_ARGS(SkTransparentShader, (buffer));
49    }
50
51    typedef SkShader INHERITED;
52};
53
54#endif
55
56