1 /*
2  * FTGL - OpenGL font library
3  *
4  * Copyright (c) 2001-2004 Henry Maddocks <ftgl@opengl.geek.nz>
5  * Copyright (c) 2008 Sam Hocevar <sam@zoy.org>
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining
8  * a copy of this software and associated documentation files (the
9  * "Software"), to deal in the Software without restriction, including
10  * without limitation the rights to use, copy, modify, merge, publish,
11  * distribute, sublicense, and/or sell copies of the Software, and to
12  * permit persons to whom the Software is furnished to do so, subject to
13  * the following conditions:
14  *
15  * The above copyright notice and this permission notice shall be
16  * included in all copies or substantial portions of the Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
19  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
21  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
22  * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25  */
26 
27 #ifndef __FTTextureFontImpl__
28 #define __FTTextureFontImpl__
29 
30 #include "FTFontImpl.h"
31 
32 #include "../FTVector.h"
33 
34 class FTTextureGlyph;
35 
36 class FTTextureFontImpl : public FTFontImpl
37 {
38     friend class FTTextureFont;
39 
40     protected:
41         FTTextureFontImpl(FTFont *ftFont, const char* fontFilePath);
42 
43         FTTextureFontImpl(FTFont *ftFont, const unsigned char *pBufferBytes,
44                           size_t bufferSizeInBytes);
45 
46         virtual ~FTTextureFontImpl();
47 
48         /**
49          * Set the char size for the current face.
50          *
51          * @param size      the face size in points (1/72 inch)
52          * @param res       the resolution of the target device.
53          * @return          <code>true</code> if size was set correctly
54          */
55         virtual bool FaceSize(const unsigned int size,
56                               const unsigned int res = 72);
57 
58         virtual FTPoint Render(const char *s, const int len,
59                                FTPoint position, FTPoint spacing,
60                                int renderMode);
61 
62         virtual FTPoint Render(const wchar_t *s, const int len,
63                                FTPoint position, FTPoint spacing,
64                                int renderMode);
65 
66     private:
67         /**
68          * Create an FTTextureGlyph object for the base class.
69          */
70         FTGlyph* MakeGlyphImpl(FT_GlyphSlot ftGlyph);
71 
72         /**
73          * Get the size of a block of memory required to layout the glyphs
74          *
75          * Calculates a width and height based on the glyph sizes and the
76          * number of glyphs. It over estimates.
77          */
78         inline void CalculateTextureSize();
79 
80         /**
81          * Creates a 'blank' OpenGL texture object.
82          *
83          * The format is GL_ALPHA and the params are
84          * GL_TEXTURE_WRAP_S = GL_CLAMP
85          * GL_TEXTURE_WRAP_T = GL_CLAMP
86          * GL_TEXTURE_MAG_FILTER = GL_LINEAR
87          * GL_TEXTURE_MIN_FILTER = GL_LINEAR
88          * Note that mipmapping is NOT used
89          */
90         inline GLuint CreateTexture();
91 
92         /**
93          * The maximum texture dimension on this OpenGL implemetation
94          */
95         GLsizei maximumGLTextureSize;
96 
97         /**
98          * The minimum texture width required to hold the glyphs
99          */
100         GLsizei textureWidth;
101 
102         /**
103          * The minimum texture height required to hold the glyphs
104          */
105         GLsizei textureHeight;
106 
107         /**
108          *An array of texture ids
109          */
110         FTVector<GLuint> textureIDList;
111 
112         /**
113          * The max height for glyphs in the current font
114          */
115         int glyphHeight;
116 
117         /**
118          * The max width for glyphs in the current font
119          */
120         int glyphWidth;
121 
122         /**
123          * A value to be added to the height and width to ensure that
124          * glyphs don't overlap in the texture
125          */
126         unsigned int padding;
127 
128         /**
129          *
130          */
131         unsigned int numGlyphs;
132 
133         /**
134          */
135         unsigned int remGlyphs;
136 
137         /**
138          */
139         int xOffset;
140 
141         /**
142          */
143         int yOffset;
144 
145         /* Internal generic Render() implementation */
146         template <typename T>
147         inline FTPoint RenderI(const T *s, const int len,
148                                FTPoint position, FTPoint spacing, int mode);
149 };
150 
151 #endif // __FTTextureFontImpl__
152 
153