nanogui: how to set the CMAP fot frame buffer?
Subject:
RE: how to set the CMAP fot frame buffer?
From:
Greg Haerr ####@####.####
Date:
24 Jun 1999 17:01:18 -0000
Message-Id: <01BEBE30.600DD720.greg@censoft.com>
Try this
/* Set NC color palettes values starting at C to red-green-blue value
specified in PALETTE. Use 8-bit color values as input. */
void
bogl_set_palette (int c, int nc, const unsigned char (*palette)[3])
{
struct fb_cmap cmap;
__u16 red[nc];
__u16 green[nc];
__u16 blue[nc];
int i;
for (i = 0; i < nc; i++)
{
const unsigned char *e = palette[i];
if (gray)
red[i] = green[i] = blue[i] = (e[0] * 77 + e[1] * 151 + e[2] * 28);
else
{
red[i] = e[0] << 8;
green[i] = e[1] << 8;
blue[i] = e[2] << 8;
}
}
cmap.start = c;
cmap.len = nc;
cmap.red = red;
cmap.green = green;
cmap.blue = blue;
cmap.transp = NULL;
if(ioctl (fb, FBIOPUTCMAP, &cmap) == -1)
printf("putcmap fail\n");
}
