rsFont.h revision 9fc9f0375a92fe22fecb3782b18a5c6060a07290 
1/*
2 * Copyright (C) 2009 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_RS_FONT_H
18#define ANDROID_RS_FONT_H
19
20#include "RenderScript.h"
21#include "rsStream.h"
22#include <utils/String8.h>
23#include <utils/Vector.h>
24#include <utils/KeyedVector.h>
25
26#include <ft2build.h>
27#include FT_FREETYPE_H
28
29// ---------------------------------------------------------------------------
30namespace android {
31
32namespace renderscript {
33
34class FontState;
35
36class Font : public ObjectBase
37{
38public:
39    ~Font();
40
41    // Pointer to the utf data, length of data, where to start, number of glyphs ot read
42    // (each glyph may be longer than a char because we are dealing with utf data)
43    // Last two variables are the initial pen position
44    void renderUTF(const char *text, uint32_t len, uint32_t start, int numGlyphs, int x, int y);
45
46    // Currently files do not get serialized,
47    // but we need to inherit from ObjectBase for ref tracking
48    virtual void serialize(OStream *stream) const {
49    }
50    virtual RsA3DClassID getClassId() const {
51        return RS_A3D_CLASS_ID_UNKNOWN;
52    }
53
54    static Font * create(Context *rsc, const char *name, uint32_t fontSize, uint32_t dpi);
55
56protected:
57
58    friend class FontState;
59
60    void invalidateTextureCache();
61    struct CachedGlyphInfo
62    {
63        // Has the cache been invalidated?
64        bool mIsValid;
65        // Location of the cached glyph in the bitmap
66        // in case we need to resize the texture
67        uint32_t mBitmapMinX;
68        uint32_t mBitmapMinY;
69        uint32_t mBitmapWidth;
70        uint32_t mBitmapHeight;
71        // Also cache texture coords for the quad
72        float mBitmapMinU;
73        float mBitmapMinV;
74        float mBitmapMaxU;
75        float mBitmapMaxV;
76        // Minimize how much we call freetype
77        FT_UInt mGlyphIndex;
78        FT_Vector mAdvance;
79        // Values below contain a glyph's origin in the bitmap
80        FT_Int mBitmapLeft;
81        FT_Int mBitmapTop;
82    };
83
84    String8 mFontName;
85    uint32_t mFontSize;
86    uint32_t mDpi;
87
88    Font(Context *rsc);
89    bool init(const char *name, uint32_t fontSize, uint32_t dpi);
90
91    FT_Face mFace;
92    bool mInitialized;
93    bool mHasKerning;
94
95    DefaultKeyedVector<uint32_t, CachedGlyphInfo* > mCachedGlyphs;
96
97    CachedGlyphInfo *cacheGlyph(uint32_t glyph);
98    void updateGlyphCache(CachedGlyphInfo *glyph);
99    void drawCachedGlyph(CachedGlyphInfo *glyph, int x, int y);
100};
101
102class FontState
103{
104public:
105    FontState();
106    ~FontState();
107
108    void init(Context *rsc);
109    void deinit(Context *rsc);
110
111    ObjectBaseRef<Font> mDefault;
112    ObjectBaseRef<Font> mLast;
113
114    void renderText(const char *text, uint32_t len, uint32_t startIndex, int numGlyphs, int x, int y);
115    void renderText(const char *text, int x, int y);
116    void renderText(Allocation *alloc, int x, int y);
117    void renderText(Allocation *alloc, uint32_t start, int len, int x, int y);
118
119    void setFontColor(float r, float g, float b, float a);
120
121protected:
122
123    friend class Font;
124
125    struct CacheTextureLine
126    {
127        uint32_t mMaxHeight;
128        uint32_t mMaxWidth;
129        uint32_t mCurrentRow;
130        uint32_t mCurrentCol;
131
132        CacheTextureLine(uint32_t maxHeight, uint32_t maxWidth, uint32_t currentRow, uint32_t currentCol) :
133            mMaxHeight(maxHeight), mMaxWidth(maxWidth), mCurrentRow(currentRow), mCurrentCol(currentCol) {
134        }
135
136        bool fitBitmap(FT_Bitmap *bitmap, uint32_t *retOriginX, uint32_t *retOriginY) {
137            if((uint32_t)bitmap->rows > mMaxHeight) {
138                return false;
139            }
140
141            if(mCurrentCol + (uint32_t)bitmap->width < mMaxWidth) {
142               *retOriginX = mCurrentCol;
143               *retOriginY = mCurrentRow;
144               mCurrentCol += bitmap->width;
145               return true;
146            }
147
148            return false;
149        }
150    };
151
152    Vector<CacheTextureLine*> mCacheLines;
153
154    Context *mRSC;
155
156    float mFontColor[4];
157    bool mFontColorDirty;
158
159    // Free type library, we only need one copy
160    FT_Library mLibrary;
161    FT_Library getLib();
162    Vector<Font*> mActiveFonts;
163
164    // Render state for the font
165    ObjectBaseRef<ProgramFragment> mFontShaderF;
166    ObjectBaseRef<Sampler> mFontSampler;
167    ObjectBaseRef<ProgramStore> mFontProgramStore;
168    void initRenderState();
169
170    // Texture to cache glyph bitmaps
171    ObjectBaseRef<Allocation> mTextTexture;
172    void initTextTexture();
173
174    bool cacheBitmap(FT_Bitmap *bitmap, uint32_t *retOriginX, uint32_t *retOriginY);
175    const Type* getCacheTextureType() {
176        return mTextTexture->getType();
177    }
178
179    void flushAllAndInvalidate();
180
181    // Pointer to vertex data to speed up frame to frame work
182    float *mTextMeshPtr;
183    uint32_t mCurrentQuadIndex;
184    uint32_t mMaxNumberOfQuads;
185
186    void initVertexArrayBuffers();
187    ObjectBaseRef<Allocation> mIndexBuffer;
188    ObjectBaseRef<Allocation> mVertexArray;
189
190
191    bool mInitialized;
192
193    void checkInit();
194
195    void issueDrawCommand();
196
197    void appendMeshQuad(float x1, float y1, float z1,
198                          float u1, float v1,
199                          float x2, float y2, float z2,
200                          float u2, float v2,
201                          float x3, float y3, float z3,
202                          float u3, float v3,
203                          float x4, float y4, float z4,
204                          float u4, float v4);
205
206};
207
208
209}
210}
211
212#endif
213