defras(3G)defras(3G)NAMEdefras - defines a raster font
FORTRAN 77 SPECIFICATION
subroutine defras(n, ht, nc, chars, nr, raster)
integer*4 n, ht, nc, nr
integer*2 chars(4*nc), raster(nr)PARAMETERS
n expects the constant that you want to use as the identifier for
this raster font. This constant is used as an index into a font
table. The default font, 0, is a fixed-pitch font with a height
of 15 and width of 9. Font 0 cannot be redefined.
ht expects the maximum height (in pixels) for a character.
nc expects the number of characters in this font.
chars expects an array of four by nc 16-bit elements. Because you will
need to write to individual bytes within the second and third
elements of the chars array, you should declare an eight by nc
array of one byte elements. You can then EQUIVALENCE the new
array to the chars array.
First element of each row expects the element number of raster
at which starts the bitmap for this character. The element
numbers start at zero.
Second element, high byte expects the number of columns in the
bitmap that contain set bits (character width). Second element,
low byte expects the number of rows (character height) in the
bitmap of the character (including ascender and descender).
Third element, high byte expects number of bitmap columns
between the start of the character's bitmap and the start of the
character. Third element, low byte expects the number rows
between the character's baseline and the bottom of the bitmap.
For characters with descenders (e.g., g) this value is a
negative number. For characters that rest entirely on the
baseline, this value is zero.
Fourth element expects the bit width of the bitmap for the
character. This value tells the system how many bits there are
in each row of the bitmap for this character.
nr expects the number of 16-bit integers in raster.
raster expects a one-dimensional array that contains all the bit maps
(masks) for the characters in the font. Each element of the
array is a 16-bit integer and the elements are ordered left to
right, bottom to top. When interpreting each element, the bits
are left justified within the character's bounding box.
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defras(3G)defras(3G)
The maximum row width for a single bitmap is not limited to the
capacity of a single 16-bit integer array element. The rows of
a bitmap may span more than one array element. However, each
new row in the character bitmap must start with its own array
element. Likewise, each new character bitmap must start with
its own array element. The system reads the row width and
starting location for a character bitmap from the in the chars
array.
DESCRIPTIONdefras defines a raster font. To replace a raster font, specify the
index of the previous font as the index for the new font. To delete a
raster font, define a font with no characters. Patterns, cursors, and
fonts are available to all windows when using multiple windows.
SEE ALSO
charst, cmov, font, getcpo, getdes, getfon, gethei, strwid
NOTE
This routine is available only in immediate mode.
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