VGA Font Editor
v4.2.0
This is a cross-platform editor and library for VGA ROM fonts. This has code for rendering text using a loaded font. The source code is written in QB64-PE and works natively without using any third party libraries.
git submodule update --init --recursive to initialize, fetch and checkout git submodulesF5 to compile and run' For rendering
FUNCTION PSF1_LoadFontFromMemory%% (buffer AS STRING, psf AS PSF1Type)
FUNCTION PSF1_LoadFontFromFile%% (fileName AS STRING, psf AS PSF1Type)
SUB PSF1_SetCurrentFont (psf AS PSF1Type)
FUNCTION PSF1_GetFontWidth~%%
FUNCTION PSF1_GetFontHeight~%%
FUNCTION PSF1_GetDrawStringWidth& (text AS STRING)
SUB PSF1_DrawCharacter (cp AS _UNSIGNED _BYTE, x AS LONG, y AS LONG)
SUB PSF1_DrawString (text AS STRING, x AS LONG, y AS LONG)
' Used by the editor
SUB PSF1_SetFontHeight (h AS _UNSIGNED _BYTE)
FUNCTION PSF1_GetFont$
FUNCTION PSF1_SetFont%% (buffer AS STRING)
FUNCTION PSF1_GetGlyphBitmap$ (cp AS _UNSIGNED _BYTE)
SUB PSF1_SetGlyphBitmap (cp AS _UNSIGNED _BYTE, bmp AS STRING)
FUNCTION PSF1_GetGlyphPixel%% (cp AS _UNSIGNED _BYTE, x AS LONG, y AS LONG)
SUB PSF1_SetGlyphPixel (cp AS _UNSIGNED _BYTE, x AS LONG, y AS LONG, b AS _BYTE)
SUB PSF1_SetGlyphDefaultBitmap (cp AS _UNSIGNED _BYTE)
FUNCTION PSF1_SaveFont%% (fileName AS STRING)What can I do with this?
fonts directory. I honestly do not know the orginal souces of these and highly recommend you to create your own fonts using this tool for your projects.What is a VGA ROM font?
How is a character stored in memory?
It's quite simple, 0 encodes background, 1 encodes foreground color. VGA fonts are always 8 bits wide so that each byte contains exactly one row. For letter 'A' in the typical 8x16 font it would be (in binary):
00000000b byte 0
00000000b byte 1
00000000b byte 2
00010000b byte 3
00111000b byte 4
01101100b byte 5
11000110b byte 6
11000110b byte 7
11111110b byte 8
11000110b byte 9
11000110b byte 10
11000110b byte 11
11000110b byte 12
00000000b byte 13
00000000b byte 14
00000000b byte 15
The full bitmap contains bitmaps for every character, thus it's 256*16 bytes, 4096 bytes long (for 8x16 fonts). If you want to get the bitmap for a specific character, you have to multiply the ASCII code by 16 (number of rows in a character for 8x16 fonts).
What are these PSF files?
These PSFs (PC Screen Font) were created using the bin2psf conversion tool from raw VGA ROM font dumps from various sources. These files are extemely small and suitable for embedded, memory limited or retro projects. The files are almost a raw dump of the VGA ROM font with just a few bytes for the header.
+--------------------------------------------+
| PSF1_MAGIC0 0x36 (1 byte) |
+--------------------------------------------+
| PSF1_MAGIC1 0x04 (1 byte) |
+--------------------------------------------+
| MODE (1 byte; set to 0) |
+--------------------------------------------+
| FONT HEIGHT (1 byte) |
+--------------------------------------------+
| CHAR 1 SCAN LINE 1 (1 byte) |
| CHAR 1 SCAN LINE 2 (1 byte) |
| CHAR 1 SCAN LINE 3 (1 byte) |
| CHAR 1 SCAN LINE 4 (1 byte) |
| CHAR 1 SCAN LINE 5 (1 byte) |
| .. |
| .. |
| .. |
| CHAR 1 SCAN LINE <FONT HEIGHT> (1 byte) |
+--------------------------------------------+
| CHAR 2 SCAN LINE 1 (1 byte) |
| CHAR 2 SCAN LINE 2 (1 byte) |
| CHAR 2 SCAN LINE 3 (1 byte) |
| CHAR 2 SCAN LINE 4 (1 byte) |
| CHAR 2 SCAN LINE 5 (1 byte) |
| .. |
| .. |
| .. |
| CHAR 2 SCAN LINE <FONT HEIGHT> (1 byte) |
+--------------------------------------------+
| .. |
| .. |
| .. |
+--------------------------------------------+
| .. |
| .. |
| .. |
+--------------------------------------------+
| .. |
| .. |
| .. |
+--------------------------------------------+
| CHAR 256 SCAN LINE 1 (1 byte) |
| CHAR 256 SCAN LINE 2 (1 byte) |
| CHAR 256 SCAN LINE 3 (1 byte) |
| CHAR 256 SCAN LINE 4 (1 byte) |
| CHAR 256 SCAN LINE 5 (1 byte) |
| .. |
| .. |
| .. |
| CHAR 256 SCAN LINE <FONT HEIGHT> (1 byte) |
+--------------------------------------------+
git submodule update --init --recursive to initialize, fetch and checkout git submodules
