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/*
* Copyright © 2024 Michael Smith <mikesmiffy128@gmail.com>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED “AS IS” AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
* INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
* LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
* OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
* PERFORMANCE OF THIS SOFTWARE.
*/
#include <string.h>
#include "intdefs.h"
void hexcolour_rgb(uchar out[static 4], const char *s) {
const char *p = s;
for (uchar *q = out; q - out < 3; ++q) {
if (*p >= '0' && *p <= '9') {
*q = *p++ - '0' << 4;
}
else if ((*p | 32) >= 'a' && (*p | 32) <= 'f') {
*q = 10 + (*p++ | 32) - 'a' << 4;
}
else {
// screw it, just fall back on white, I guess.
// note: this also handles *p == '\0' so we don't overrun the string
memset(out, 255, 4); // should be a single mov
return;
}
// repetitive unrolled nonsense
if (*p >= '0' && *p <= '9') {
*q |= *p++ - '0';
}
else if ((*p | 32) >= 'a' && (*p | 32) <= 'f') {
*q |= 10 + (*p++ | 32) - 'a';
}
else {
memset(out, 255, 4); // should be a single mov
return;
}
}
//out[3] = 255; // never changes!
}
void hexcolour_rgba(uchar out[static 4], const char *s) {
const char *p = s;
// same again but with 4 pairs of digits instead of 3!
for (uchar *q = out; q - out < 4; ++q) {
if (*p >= '0' && *p <= '9') {
*q = *p++ - '0' << 4;
}
else if ((*p | 32) >= 'a' && (*p | 32) <= 'f') {
*q = 10 + (*p++ | 32) - 'a' << 4;
}
else {
if (q - out == 3 && !*p) {
// ONLY if both the last alpha digits are missing: use provided
// RGB at full opacity. otherwise same white fallback as before.
out[3] = 255;
return;
}
memset(out, 255, 4);
return;
}
// even more repetitive unrolled nonsense
if (*p >= '0' && *p <= '9') {
*q |= *p++ - '0';
}
else if ((*p | 32) >= 'a' && (*p | 32) <= 'f') {
*q |= 10 + (*p++ | 32) - 'a';
}
else {
memset(out, 255, 4);
return;
}
}
}
// vi: sw=4 ts=4 noet tw=80 cc=80
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