rsFont.h revision a1ccecd965c07c2739f1258989526051a010bdab 
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
119protected:
120
121    friend class Font;
122
123    struct CacheTextureLine
124    {
125        uint32_t mMaxHeight;
126        uint32_t mMaxWidth;
127        uint32_t mCurrentRow;
128        uint32_t mCurrentCol;
129
130        CacheTextureLine(uint32_t maxHeight, uint32_t maxWidth, uint32_t currentRow, uint32_t currentCol) :
131            mMaxHeight(maxHeight), mMaxWidth(maxWidth), mCurrentRow(currentRow), mCurrentCol(currentCol) {
132        }
133
134        bool fitBitmap(FT_Bitmap *bitmap, uint32_t *retOriginX, uint32_t *retOriginY) {
135            if((uint32_t)bitmap->rows > mMaxHeight) {
136                return false;
137            }
138
139            if(mCurrentCol + (uint32_t)bitmap->width < mMaxWidth) {
140               *retOriginX = mCurrentCol;
141               *retOriginY = mCurrentRow;
142               mCurrentCol += bitmap->width;
143               return true;
144            }
145
146            return false;
147        }
148    };
149
150    Vector<CacheTextureLine*> mCacheLines;
151
152    Context *mRSC;
153
154    // Free type library, we only need one copy
155    FT_Library mLibrary;
156    FT_Library getLib();
157    Vector<Font*> mActiveFonts;
158
159    // Render state for the font
160    ObjectBaseRef<ProgramFragment> mFontShaderF;
161    ObjectBaseRef<Sampler> mFontSampler;
162    ObjectBaseRef<ProgramStore> mFontProgramStore;
163    void initRenderState();
164
165    // Texture to cache glyph bitmaps
166    ObjectBaseRef<Allocation> mTextTexture;
167    void initTextTexture();
168
169    bool cacheBitmap(FT_Bitmap *bitmap, uint32_t *retOriginX, uint32_t *retOriginY);
170    const Type* getCacheTextureType() {
171        return mTextTexture->getType();
172    }
173
174    void flushAllAndInvalidate();
175
176    // Pointer to vertex data to speed up frame to frame work
177    float *mTextMeshPtr;
178    uint32_t mCurrentQuadIndex;
179    uint32_t mMaxNumberOfQuads;
180
181    void initVertexArrayBuffers();
182    ObjectBaseRef<Allocation> mIndexBuffer;
183    ObjectBaseRef<Allocation> mVertexArray;
184
185
186    bool mInitialized;
187
188    void checkInit();
189
190    void issueDrawCommand();
191
192    void appendMeshQuad(float x1, float y1, float z1,
193                          float u1, float v1,
194                          float x2, float y2, float z2,
195                          float u2, float v2,
196                          float x3, float y3, float z3,
197                          float u3, float v3,
198                          float x4, float y4, float z4,
199                          float u4, float v4);
200
201};
202
203
204}
205}
206
207#endif
208