get_colorpixel support for non-true color displays

Re-introduce fully-fledged get_colorpixel function, which enables arbitrary
color depths for the display.  The previous code is kept as an optimization for
the case of a true color display, where a X11 roundtrip is unnecessary.
This commit is contained in:
Alex Auvolat 2015-12-28 12:58:32 +01:00
parent c6a4e4519f
commit 287a0b4c3c

View File

@ -9,21 +9,28 @@
#include <stdint.h>
#include <string.h>
#include "queue.h"
#include "libi3.h"
struct Colorpixel {
char *hex;
uint32_t pixel;
SLIST_ENTRY(Colorpixel)
colorpixels;
};
SLIST_HEAD(colorpixel_head, Colorpixel)
colorpixels;
/*
* Returns the colorpixel to use for the given hex color (think of HTML). Only
* works for true-color (vast majority of cases) at the moment, avoiding a
* roundtrip to X11.
* Returns the colorpixel to use for the given hex color (think of HTML).
*
* The hex_color has to start with #, for example #FF00FF.
*
* NOTE that get_colorpixel() does _NOT_ check the given color code for validity.
* This has to be done by the caller.
*
* NOTE that this function may in the future rely on a global xcb_connection_t
* variable called 'conn' to be present.
*
*/
uint32_t get_colorpixel(const char *hex) {
char strgroups[3][3] = {
@ -34,5 +41,43 @@ uint32_t get_colorpixel(const char *hex) {
uint8_t g = strtol(strgroups[1], NULL, 16);
uint8_t b = strtol(strgroups[2], NULL, 16);
return (0xFF << 24) | (r << 16 | g << 8 | b);
/* Shortcut: if our screen is true color, no need to do a roundtrip to X11 */
if (root_screen->root_depth == 24 || root_screen->root_depth == 32) {
return (0xFF << 24) | (r << 16 | g << 8 | b);
}
/* Lookup this colorpixel in the cache */
struct Colorpixel *colorpixel;
SLIST_FOREACH(colorpixel, &(colorpixels), colorpixels) {
if (strcmp(colorpixel->hex, hex) == 0)
return colorpixel->pixel;
}
#define RGB_8_TO_16(i) (65535 * ((i)&0xFF) / 255)
int r16 = RGB_8_TO_16(r);
int g16 = RGB_8_TO_16(g);
int b16 = RGB_8_TO_16(b);
xcb_alloc_color_reply_t *reply;
reply = xcb_alloc_color_reply(conn, xcb_alloc_color(conn, root_screen->default_colormap,
r16, g16, b16),
NULL);
if (!reply) {
LOG("Could not allocate color\n");
exit(1);
}
uint32_t pixel = reply->pixel;
free(reply);
/* Store the result in the cache */
struct Colorpixel *cache_pixel = scalloc(1, sizeof(struct Colorpixel));
cache_pixel->hex = sstrdup(hex);
cache_pixel->pixel = pixel;
SLIST_INSERT_HEAD(&(colorpixels), cache_pixel, colorpixels);
return pixel;
}