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Diffstat (limited to 'docs')
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1 | Description of the binary AJF font file format | ||
2 | |||
3 | Index Descripton | ||
4 | |||
5 | 00 MAGIC1 (0xBD) | ||
6 | 01 MAGIC2 (0xFC) used to make sure this is an ajf font | ||
7 | 02 Unused, planned use: "code page" | ||
8 | 03 - 22 ASCII text holding the font name | ||
9 | 23 - 24 "bound width" (high 8 bits, low 8 bits) | ||
10 | 25 - 26 "bound height" (high 8 bits, low 8 bits) | ||
11 | 26 - 28 first character in the font | ||
12 | 29 - 2a 0x00ff (supposed number of characters in the font?) | ||
13 | 2b - map offset table starts here. Each offset entry is supposed to be | ||
14 | three bytes: width, offset highbyte, offset lowbyte | ||
15 | The offset is a relative offset, counted in bytes, to where in the | ||
16 | font data this particular char's bitmap image starts. | ||
17 | |||
18 | font data, in Rockbox-internal image-format. That means column-wise | ||
19 | left-to-right for the full width, the first 8 pixels of height. Then | ||
20 | follows the next 8 pixels of height left-to-right. | ||
21 | |||
22 | We don't currently support fonts larger than 16 pixels. | ||