I guess I must be an old school type of programmer. About 1975 each student
seemed to have a program they developed. I used a Fortran program that had 3
arrays each 10 characters deep. You scaled the picture value into the range
0-9 and used the value as an offset into the array. You printed the line 3
time with out a line feed and then issued a line feed.
Example:
picture value array 1 array2 array3
0 space space space
1 period space space
2 colon space space
3 plus space space
.
.
.
9 0 W M
With this scheme you could build up a fairly dark spot for black points.
Later versions included image processing to improve the look of the image.
Histogram equalization makes visually much better pictures. Early weather
maps are a good example of this type of image. I remember seeing punch card
decks that had ASCII pictures in comments at the beginning. It made it easy
to see if your output was coming off the printer when you saw the picture in
the source.
Mike
"old code dog"