load_bitmap_font
Grabs a font from a bitmap file.
Description
Tries to grab a font from a bitmap. The bitmap can be in any format that
load_bitmap understands.
The size of each character is determined by the layout of the image, which
should be a rectangular grid containing all the ASCII characters from
space (32) up to the tilde (126). The way the characters are separated
depends on the colordepth of the image file:
-
paletted (8 bit) image file
Use color 0 for the transparent portions of the characters and fill the
spaces between each letter with color 255.
-
High (15/16 bit) and true (24/32 bit) color image file
Use bright pink (maximum red and blue, zero green) for the transparent
portions of the characters and fill the spaces between each letter with
bright yellow (maximum red and green, zero blue).
Note that in each horizontal row the bounding boxes around the characters
should align and have the same height.
Probably the easiest way to get to grips with how this works is to load up
the `demo.dat' file and export the TITLE_FONT into a PCX file. Have a look
at the resulting picture in your paint program: that is the format a font
should be in.
Take care with high and true color fonts: Allegro will convert these to the
current colordepth when you load the font. If you try to use a font on
a bitmap with a different color depth Allegro will do color conversions on
the fly, which will be rather slow. For optimal performance you should
set the colordepth to the colordepth you want to use before loading any
fonts.
Returns a pointer to the font or NULL on error. Remember that you are
responsible for destroying the font when you are finished with it to
avoid memory leaks.
Related Projects
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