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authorPeter Korsgaard <jacmet@sunsite.dk>2011-10-17 05:31:52 +0200
committerDenys Vlasenko <vda.linux@googlemail.com>2011-10-17 05:31:52 +0200
commitcd06e06eee3ef89e45b60d7122e5518995c7f65e (patch)
tree27856d2e966353f4d332dcb609f81d348eb1415c
parente4fa7b7965fd574cff2a6a9b877522d613804a38 (diff)
downloadbusybox-cd06e06eee3ef89e45b60d7122e5518995c7f65e.tar.gz
fbsplash: support 8bit mode
Fake truecolor support using a RGB:332 palette. function old new delta fb_setpal - 172 +172 fbsplash_main 920 953 +33 fb_pixel_value 50 80 +30 fb_write_pixel 47 51 +4 ------------------------------------------------------------------------------ (add/remove: 1/0 grow/shrink: 3/0 up/down: 239/0) Total: 239 bytes Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
-rw-r--r--miscutils/fbsplash.c69
1 files changed, 64 insertions, 5 deletions
diff --git a/miscutils/fbsplash.c b/miscutils/fbsplash.c
index bc9ac8fe1..04d583df6 100644
--- a/miscutils/fbsplash.c
+++ b/miscutils/fbsplash.c
@@ -74,6 +74,43 @@ struct globals {
#define DEBUG_MESSAGE(...) ((void)0)
#endif
+/**
+ * Configure palette for RGB:332
+ */
+static void fb_setpal(int fd)
+{
+ struct fb_cmap cmap;
+ /* fb colors are 16 bit */
+ unsigned short red[256], green[256], blue[256];
+ unsigned i;
+
+ /* RGB:332 */
+ for (i = 0; i < 256; i++) {
+ /* Color is encoded in pixel value as rrrgggbb.
+ * 3-bit color is mapped to 16-bit one as:
+ * 000 -> 00000000 00000000
+ * 001 -> 00100100 10010010
+ * ...
+ * 011 -> 01101101 10110110
+ * 100 -> 10010010 01001001
+ * ...
+ * 111 -> 11111111 11111111
+ */
+ red[i] = (( i >> 5 ) * 0x9249) >> 2; // rrr * 00 10010010 01001001 >> 2
+ green[i] = (((i >> 2) & 0x7) * 0x9249) >> 2; // ggg * 00 10010010 01001001 >> 2
+ /* 2-bit color is easier: */
+ blue[i] = ( i & 0x3) * 0x5555; // bb * 01010101 01010101
+ }
+
+ cmap.start = 0;
+ cmap.len = 256;
+ cmap.red = red;
+ cmap.green = green;
+ cmap.blue = blue;
+ cmap.transp = 0;
+
+ xioctl(fd, FBIOPUTCMAP, &cmap);
+}
/**
* Open and initialize the framebuffer device
@@ -87,8 +124,21 @@ static void fb_open(const char *strfb_device)
xioctl(fbfd, FBIOGET_VSCREENINFO, &G.scr_var);
xioctl(fbfd, FBIOGET_FSCREENINFO, &G.scr_fix);
- if (G.scr_var.bits_per_pixel < 16 || G.scr_var.bits_per_pixel > 32)
+ switch (G.scr_var.bits_per_pixel) {
+ case 8:
+ fb_setpal(fbfd);
+ break;
+
+ case 16:
+ case 24:
+ case 32:
+ break;
+
+ default:
bb_error_msg_and_die("unsupported %u bpp", (int)G.scr_var.bits_per_pixel);
+ break;
+ }
+
G.bytes_per_pixel = (G.scr_var.bits_per_pixel + 7) >> 3;
// map the device in memory
@@ -109,11 +159,17 @@ static void fb_open(const char *strfb_device)
*/
static unsigned fb_pixel_value(unsigned r, unsigned g, unsigned b)
{
+ if (G.bytes_per_pixel == 1) {
+ r = r & 0xe0; // 3-bit red
+ g = (g >> 3) & 0x1c; // 3-bit green
+ b = b >> 6; // 2-bit blue
+ return r + g + b;
+ }
if (G.bytes_per_pixel == 2) {
- r >>= 3; // 5-bit red
- g >>= 2; // 6-bit green
- b >>= 3; // 5-bit blue
- return b + (g << 5) + (r << (5+6));
+ r = (r & 0xf8) << 8; // 5-bit red
+ g = (g & 0xfc) << 3; // 6-bit green
+ b = b >> 3; // 5-bit blue
+ return r + g + b;
}
// RGB 888
return b + (g << 8) + (r << 16);
@@ -125,6 +181,9 @@ static unsigned fb_pixel_value(unsigned r, unsigned g, unsigned b)
static void fb_write_pixel(unsigned char *addr, unsigned pixel)
{
switch (G.bytes_per_pixel) {
+ case 1:
+ *addr = pixel;
+ break;
case 2:
*(uint16_t *)addr = pixel;
break;