80 lines
1.9 KiB
Plaintext
80 lines
1.9 KiB
Plaintext
8x8 monochrome bitmap font for rendering
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=========================================
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A collection of header files containing a 8x8 bitmap font.
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font8x8.h contains all available characters
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font8x8_basic.h contains unicode points U+0000 - U+007F
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font8x8_latin.h contains unicode points U+0000 - U+00FF
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Author: Daniel Hepper <daniel@hepper.net>
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License: Public Domain
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Encoding
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========
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Every character in the font is encoded row-wise in 8 bytes.
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The least significant bit of each byte corresponds to the first pixel in a
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row.
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The character 'A' (0x41 / 65) is encoded as
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{ 0x0C, 0x1E, 0x33, 0x33, 0x3F, 0x33, 0x33, 0x00}
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0x0C => 0000 1100 => ..XX....
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0X1E => 0001 1110 => .XXXX...
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0x33 => 0011 0011 => XX..XX..
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0x33 => 0011 0011 => XX..XX..
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0x3F => 0011 1111 => xxxxxx..
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0x33 => 0011 0011 => XX..XX..
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0x33 => 0011 0011 => XX..XX..
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0x00 => 0000 0000 => ........
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To access the nth pixel in a row, right-shift by n.
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. . X X . . . .
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| | | | | | | |
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(0x0C >> 0) & 1 == 0-+ | | | | | | |
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(0x0C >> 1) & 1 == 0---+ | | | | | |
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(0x0C >> 2) & 1 == 1-----+ | | | | |
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(0x0C >> 3) & 1 == 1-------+ | | | |
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(0x0C >> 4) & 1 == 0---------+ | | |
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(0x0C >> 5) & 1 == 0-----------+ | |
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(0x0C >> 6) & 1 == 0-------------+ |
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(0x0C >> 7) & 1 == 0---------------+
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Renderer
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========
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To visualize the font, a simple renderer is included in render.c
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$ gcc render.c -o render
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$ ./render 65
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XX
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XXXX
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XX XX
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XX XX
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XXXXXX
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XX XX
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XX XX
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Credits
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=======
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These header files are directly derived from an assembler file fetched from:
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http://dimensionalrift.homelinux.net/combuster/mos3/?p=viewsource&file=/modules/gfx/font8_8.asm
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Original header:
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; Summary: font8_8.asm
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; 8x8 monochrome bitmap fonts for rendering
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;
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; Author:
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; Marcel Sondaar
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; International Business Machines (public domain VGA fonts)
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;
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; License:
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; Public Domain
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;
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