rsFont.h revision d3e0ad43dc758c409fc23d1893dab67b18520c24 
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        // Hold on to the bitmap in case cache is invalidated
83        FT_Bitmap mBitmap;
84        bool mBitmapValid;
85    };
86
87    String8 mFontName;
88    uint32_t mFontSize;
89    uint32_t mDpi;
90
91    Font(Context *rsc);
92    bool init(const char *name, uint32_t fontSize, uint32_t dpi);
93
94    FT_Face mFace;
95    bool mInitialized;
96    bool mHasKerning;
97
98    DefaultKeyedVector<uint32_t, CachedGlyphInfo* > mCachedGlyphs;
99
100    CachedGlyphInfo *cacheGlyph(uint32_t glyph);
101    void updateGlyphCache(CachedGlyphInfo *glyph);
102    void drawCachedGlyph(CachedGlyphInfo *glyph, int x, int y);
103};
104
105class FontState
106{
107public:
108    FontState();
109    ~FontState();
110
111    void init(Context *rsc);
112    void deinit(Context *rsc);
113
114    ObjectBaseRef<Font> mDefault;
115    ObjectBaseRef<Font> mLast;
116
117    void renderText(const char *text, uint32_t len, uint32_t startIndex, int numGlyphs, int x, int y);
118    void renderText(const char *text, int x, int y);
119    void renderText(Allocation *alloc, int x, int y);
120    void renderText(Allocation *alloc, uint32_t start, int len, int x, int y);
121
122protected:
123
124    friend class Font;
125
126    struct CacheTextureLine
127    {
128        uint32_t mMaxHeight;
129        uint32_t mMaxWidth;
130        uint32_t mCurrentRow;
131        uint32_t mCurrentCol;
132
133        CacheTextureLine(uint32_t maxHeight, uint32_t maxWidth, uint32_t currentRow, uint32_t currentCol) :
134            mMaxHeight(maxHeight), mMaxWidth(maxWidth), mCurrentRow(currentRow), mCurrentCol(currentCol) {
135        }
136
137        bool fitBitmap(FT_Bitmap *bitmap, uint32_t *retOriginX, uint32_t *retOriginY) {
138            if((uint32_t)bitmap->rows > mMaxHeight) {
139                return false;
140            }
141
142            if(mCurrentCol + (uint32_t)bitmap->width < mMaxWidth) {
143               *retOriginX = mCurrentCol;
144               *retOriginY = mCurrentRow;
145               mCurrentCol += bitmap->width;
146               return true;
147            }
148
149            return false;
150        }
151    };
152
153    Vector<CacheTextureLine*> mCacheLines;
154
155    Context *mRSC;
156
157    // Free type library, we only need one copy
158    FT_Library mLibrary;
159    Vector<Font*> mActiveFonts;
160
161    // Render state for the font
162    ObjectBaseRef<ProgramFragment> mFontShaderF;
163    ObjectBaseRef<Sampler> mFontSampler;
164    ObjectBaseRef<ProgramStore> mFontProgramStore;
165    void initRenderState();
166
167    // Texture to cache glyph bitmaps
168    ObjectBaseRef<Allocation> mTextTexture;
169    void initTextTexture();
170
171    bool cacheBitmap(FT_Bitmap *bitmap, uint32_t *retOriginX, uint32_t *retOriginY);
172    const Type* getCacheTextureType() {
173        return mTextTexture->getType();
174    }
175
176    void flushAllAndInvalidate();
177
178    // Pointer to vertex data to speed up frame to frame work
179    float *mTextMeshPtr;
180    uint32_t mCurrentQuadIndex;
181    uint32_t mMaxNumberOfQuads;
182
183    void initVertexArrayBuffers();
184    ObjectBaseRef<Allocation> mIndexBuffer;
185    ObjectBaseRef<Allocation> mVertexArray;
186
187
188    bool mInitialized;
189
190    void checkInit();
191
192    void issueDrawCommand();
193
194    void appendMeshQuad(float x1, float y1, float z1,
195                          float u1, float v1,
196                          float x2, float y2, float z2,
197                          float u2, float v2,
198                          float x3, float y3, float z3,
199                          float u3, float v3,
200                          float x4, float y4, float z4,
201                          float u4, float v4);
202
203};
204
205
206}
207}
208
209#endif
210