GammaFontRenderer.h revision 42ddc18d108f789705ad4eb697ce9599ad322507 
1/*
2 * Copyright (C) 2010 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 ANDROID_HWUI_GAMMA_FONT_RENDERER_H
18#define ANDROID_HWUI_GAMMA_FONT_RENDERER_H
19
20#include <SkPaint.h>
21
22#include "FontRenderer.h"
23#include "Program.h"
24
25namespace android {
26namespace uirenderer {
27
28class GammaFontRenderer {
29public:
30    virtual ~GammaFontRenderer();
31
32    virtual void clear() = 0;
33    virtual void flush() = 0;
34
35    virtual FontRenderer& getFontRenderer(const SkPaint* paint) = 0;
36
37    virtual uint32_t getFontRendererCount() const = 0;
38    virtual uint32_t getFontRendererSize(uint32_t fontRenderer, GLenum format) const = 0;
39
40    virtual void describe(ProgramDescription& description, const SkPaint* paint) const = 0;
41    virtual void setupProgram(ProgramDescription& description, Program* program) const = 0;
42
43    virtual void endPrecaching() = 0;
44
45    static GammaFontRenderer* createRenderer();
46
47protected:
48    GammaFontRenderer();
49
50    int mBlackThreshold;
51    int mWhiteThreshold;
52
53    float mGamma;
54};
55
56class ShaderGammaFontRenderer: public GammaFontRenderer {
57public:
58    ~ShaderGammaFontRenderer() {
59        delete mRenderer;
60    }
61
62    void clear() {
63        delete mRenderer;
64        mRenderer = NULL;
65    }
66
67    void flush() {
68        if (mRenderer) {
69            mRenderer->flushLargeCaches();
70        }
71    }
72
73    FontRenderer& getFontRenderer(const SkPaint* /* paint */) {
74        if (!mRenderer) {
75            mRenderer = new FontRenderer;
76        }
77        return *mRenderer;
78    }
79
80    uint32_t getFontRendererCount() const {
81        return 1;
82    }
83
84    uint32_t getFontRendererSize(uint32_t /* fontRenderer */, GLenum format) const {
85        return mRenderer ? mRenderer->getCacheSize(format) : 0;
86    }
87
88    void describe(ProgramDescription& description, const SkPaint* paint) const;
89    void setupProgram(ProgramDescription& description, Program* program) const;
90
91    void endPrecaching();
92
93private:
94    ShaderGammaFontRenderer(bool multiGamma);
95
96    FontRenderer* mRenderer;
97    bool mMultiGamma;
98
99    friend class GammaFontRenderer;
100};
101
102class LookupGammaFontRenderer: public GammaFontRenderer {
103public:
104    ~LookupGammaFontRenderer() {
105        delete mRenderer;
106    }
107
108    void clear() {
109        delete mRenderer;
110        mRenderer = NULL;
111    }
112
113    void flush() {
114        if (mRenderer) {
115            mRenderer->flushLargeCaches();
116        }
117    }
118
119    FontRenderer& getFontRenderer(const SkPaint* /* paint */) {
120        if (!mRenderer) {
121            mRenderer = new FontRenderer;
122            mRenderer->setGammaTable(&mGammaTable[0]);
123        }
124        return *mRenderer;
125    }
126
127    uint32_t getFontRendererCount() const {
128        return 1;
129    }
130
131    uint32_t getFontRendererSize(uint32_t /* fontRenderer */, GLenum format) const {
132        return mRenderer ? mRenderer->getCacheSize(format) : 0;
133    }
134
135    void describe(ProgramDescription& /* description */, const SkPaint* /* paint */) const {
136    }
137
138    void setupProgram(ProgramDescription& /* description */, Program* /* program */) const {
139    }
140
141    void endPrecaching();
142
143private:
144    LookupGammaFontRenderer();
145
146    FontRenderer* mRenderer;
147    uint8_t mGammaTable[256];
148
149    friend class GammaFontRenderer;
150};
151
152class Lookup3GammaFontRenderer: public GammaFontRenderer {
153public:
154    ~Lookup3GammaFontRenderer();
155
156    void clear();
157    void flush();
158
159    FontRenderer& getFontRenderer(const SkPaint* paint);
160
161    uint32_t getFontRendererCount() const {
162        return kGammaCount;
163    }
164
165    uint32_t getFontRendererSize(uint32_t fontRenderer, GLenum format) const {
166        if (fontRenderer >= kGammaCount) return 0;
167
168        FontRenderer* renderer = mRenderers[fontRenderer];
169        if (!renderer) return 0;
170
171        return renderer->getCacheSize(format);
172    }
173
174    void describe(ProgramDescription& /* description */, const SkPaint* /* paint */) const {
175    }
176
177    void setupProgram(ProgramDescription& /* description */, Program* /* program */) const {
178    }
179
180    void endPrecaching();
181
182private:
183    Lookup3GammaFontRenderer();
184
185    enum Gamma {
186        kGammaDefault = 0,
187        kGammaBlack = 1,
188        kGammaWhite = 2,
189        kGammaCount = 3
190    };
191
192    FontRenderer* getRenderer(Gamma gamma);
193
194    uint32_t mRenderersUsageCount[kGammaCount];
195    FontRenderer* mRenderers[kGammaCount];
196
197    uint8_t mGammaTable[256 * kGammaCount];
198
199    friend class GammaFontRenderer;
200};
201
202}; // namespace uirenderer
203}; // namespace android
204
205#endif // ANDROID_HWUI_GAMMA_FONT_RENDERER_H
206