rsFont.h revision e7ae69f4a70f1813cf8086ebd9714192c635300a 
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    CachedGlyphInfo* getCachedUTFChar(int32_t utfChar);
97
98    CachedGlyphInfo *cacheGlyph(uint32_t glyph);
99    void updateGlyphCache(CachedGlyphInfo *glyph);
100    void drawCachedGlyph(CachedGlyphInfo *glyph, int x, int y);
101};
102
103class FontState
104{
105public:
106    FontState();
107    ~FontState();
108
109    void init(Context *rsc);
110    void deinit(Context *rsc);
111
112    ObjectBaseRef<Font> mDefault;
113    ObjectBaseRef<Font> mLast;
114
115    void renderText(const char *text, uint32_t len, uint32_t startIndex, int numGlyphs, int x, int y);
116    void renderText(const char *text, int x, int y);
117    void renderText(Allocation *alloc, int x, int y);
118    void renderText(Allocation *alloc, uint32_t start, int len, int x, int y);
119
120    void setFontColor(float r, float g, float b, float a);
121    void getFontColor(float *r, float *g, float *b, float *a) const;
122
123protected:
124
125    friend class Font;
126
127    struct CacheTextureLine
128    {
129        uint32_t mMaxHeight;
130        uint32_t mMaxWidth;
131        uint32_t mCurrentRow;
132        uint32_t mCurrentCol;
133        bool mDirty;
134
135        CacheTextureLine(uint32_t maxHeight, uint32_t maxWidth, uint32_t currentRow, uint32_t currentCol) :
136            mMaxHeight(maxHeight), mMaxWidth(maxWidth), mCurrentRow(currentRow), mCurrentCol(currentCol),
137            mDirty(false)  {
138        }
139
140        bool fitBitmap(FT_Bitmap *bitmap, uint32_t *retOriginX, uint32_t *retOriginY) {
141            if((uint32_t)bitmap->rows > mMaxHeight) {
142                return false;
143            }
144
145            if(mCurrentCol + (uint32_t)bitmap->width < mMaxWidth) {
146               *retOriginX = mCurrentCol;
147               *retOriginY = mCurrentRow;
148               mCurrentCol += bitmap->width;
149               mDirty = true;
150               return true;
151            }
152
153            return false;
154        }
155    };
156
157    Vector<CacheTextureLine*> mCacheLines;
158    uint32_t getRemainingCacheCapacity();
159
160    void precacheLatin(Font *font);
161    String8 mLatinPrecache;
162
163    Context *mRSC;
164
165    float mFontColor[4];
166    bool mFontColorDirty;
167
168    // Free type library, we only need one copy
169    FT_Library mLibrary;
170    FT_Library getLib();
171    Vector<Font*> mActiveFonts;
172
173    // Render state for the font
174    ObjectBaseRef<Allocation> mFontShaderFConstant;
175    ObjectBaseRef<ProgramFragment> mFontShaderF;
176    ObjectBaseRef<Sampler> mFontSampler;
177    ObjectBaseRef<ProgramStore> mFontProgramStore;
178    void initRenderState();
179
180    // Texture to cache glyph bitmaps
181    ObjectBaseRef<Allocation> mTextTexture;
182    void initTextTexture();
183
184    bool cacheBitmap(FT_Bitmap *bitmap, uint32_t *retOriginX, uint32_t *retOriginY);
185    const Type* getCacheTextureType() {
186        return mTextTexture->getType();
187    }
188
189    void flushAllAndInvalidate();
190
191    // Pointer to vertex data to speed up frame to frame work
192    float *mTextMeshPtr;
193    uint32_t mCurrentQuadIndex;
194    uint32_t mMaxNumberOfQuads;
195
196    void initVertexArrayBuffers();
197    ObjectBaseRef<Allocation> mIndexBuffer;
198    ObjectBaseRef<Allocation> mVertexArray;
199
200
201    bool mInitialized;
202
203    void checkInit();
204
205    void issueDrawCommand();
206
207    void appendMeshQuad(float x1, float y1, float z1,
208                          float u1, float v1,
209                          float x2, float y2, float z2,
210                          float u2, float v2,
211                          float x3, float y3, float z3,
212                          float u3, float v3,
213                          float x4, float y4, float z4,
214                          float u4, float v4);
215
216};
217
218
219}
220}
221
222#endif
223