[PATCH] fbcon: Saner 16-color to 4-color conversion

Currently, the default linux 16-colors are converted to 4-colors by simply
dividing the values by 4.  However, this is not necessarily correct since the
first 4 colors are converted to black, rendering them invisible.

So, for black, no conversion; for light colors, convert to gray, for normal
text color, no conversion, and for bright colors, convert to intense white.

Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Antonino A. Daplas 2005-09-09 13:04:38 -07:00 committed by Linus Torvalds
parent b8c909454f
commit 2cc38ed13f
1 changed files with 19 additions and 2 deletions

View File

@ -247,9 +247,26 @@ static inline int get_color(struct vc_data *vc, struct fb_info *info,
case 2:
/*
* Scale down 16-colors to 4 colors. Default 4-color palette
* is grayscale.
* is grayscale. However, simply dividing the values by 4
* will not work, as colors 1, 2 and 3 will be scaled-down
* to zero rendering them invisible. So empirically convert
* colors to a sane 4-level grayscale.
*/
color /= 4;
switch (color) {
case 0:
color = 0; /* black */
break;
case 1 ... 6:
color = 2; /* white */
break;
case 7 ... 8:
color = 1; /* gray */
break;
default:
color = 3; /* intense white */
break;
}
break;
case 3:
/*
* Last 8 entries of default 16-color palette is a more intense