struct fb_var_screeninfo scr_var;
struct fb_fix_screeninfo scr_fix;
unsigned bytes_per_pixel;
+ // cached (8 - scr_var.COLOR.length):
+ unsigned red_shift;
+ unsigned green_shift;
+ unsigned blue_shift;
};
#define G (*ptr_to_globals)
#define INIT_G() do { \
break;
}
+ G.red_shift = 8 - G.scr_var.red.length;
+ G.green_shift = 8 - G.scr_var.green.length;
+ G.blue_shift = 8 - G.scr_var.blue.length;
G.bytes_per_pixel = (G.scr_var.bits_per_pixel + 7) >> 3;
// map the device in memory
G.addr = mmap(NULL,
- G.scr_var.yres * G.scr_fix.line_length,
+ G.scr_var.yres * G.scr_fix.line_length,
PROT_WRITE, MAP_SHARED, fbfd, 0);
if (G.addr == MAP_FAILED)
bb_perror_msg_and_die("mmap");
/**
- * Return pixel value of the passed RGB color
+ * Return pixel value of the passed RGB color.
+ * This is performance critical fn.
*/
static unsigned fb_pixel_value(unsigned r, unsigned g, unsigned b)
{
+ /* We assume that the r,g,b values are <= 255 */
+
if (G.bytes_per_pixel == 1) {
r = r & 0xe0; // 3-bit red
g = (g >> 3) & 0x1c; // 3-bit green
return r + g + b;
}
if (G.bytes_per_pixel == 2) {
- r = (r & 0xf8) << 8; // 5-bit red
- g = (g & 0xfc) << 3; // 6-bit green
- b = b >> 3; // 5-bit blue
- return r + g + b;
+ // ARM PL110 on Integrator/CP has RGBA5551 bit arrangement.
+ // We want to support bit locations like that.
+ //
+ // First shift out unused bits
+ r = r >> G.red_shift;
+ g = g >> G.green_shift;
+ b = b >> G.blue_shift;
+ // Then shift the remaining bits to their offset
+ return (r << G.scr_var.red.offset) +
+ (g << G.scr_var.green.offset) +
+ (b << G.scr_var.blue.offset);
}
// RGB 888
return b + (g << 8) + (r << 16);
pos_x = left_x;
if (percent > 0) {
- int y;
- unsigned i;
+ int i, y;
// actual progress bar
pos_x += (unsigned)(width * percent) / 100;
while (i >= 0) {
// draw one-line thick "rectangle"
// top line will have gray lvl 200, bottom one 100
- unsigned gray_level = 100 + i*100 / height;
+ unsigned gray_level = 100 + (unsigned)i*100 / height;
fb_drawfullrectangle(
left_x, y, pos_x, y,
gray_level, gray_level, gray_level);