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authorNicholas Marriott <nicm@openbsd.org>2011-08-22 10:14:15 +0000
committerNicholas Marriott <nicm@openbsd.org>2011-08-22 10:14:15 +0000
commit47d41d0203894c6792caf7f71108e8c5a9086776 (patch)
treebf666736dd75a0429012613145e030936bddd2f5 /colour.c
parent3657aa675e47eafcfa1e1186c3f4c51c4e5b6a7e (diff)
There is no need to use sqrt()/INFINITY here which simplifies the code
and makes it more portable, from Havard Eidnes.
Diffstat (limited to 'colour.c')
-rw-r--r--colour.c12
1 files changed, 5 insertions, 7 deletions
diff --git a/colour.c b/colour.c
index 3530686a..ae69e88f 100644
--- a/colour.c
+++ b/colour.c
@@ -19,7 +19,6 @@
#include <sys/types.h>
#include <ctype.h>
-#include <math.h>
#include <stdlib.h>
#include <string.h>
@@ -41,7 +40,7 @@ struct colour_rgb {
struct colour_rgb *colour_rgb_256;
void colour_rgb_generate256(void);
-double colour_rgb_distance(struct colour_rgb *, struct colour_rgb *);
+u_int colour_rgb_distance(struct colour_rgb *, struct colour_rgb *);
int colour_rgb_find(struct colour_rgb *);
/* Generate 256 colour RGB table. */
@@ -91,7 +90,7 @@ colour_rgb_generate256(void)
}
/* Get colour RGB distance. */
-double
+u_int
colour_rgb_distance(struct colour_rgb *rgb1, struct colour_rgb *rgb2)
{
int r, g, b;
@@ -99,21 +98,20 @@ colour_rgb_distance(struct colour_rgb *rgb1, struct colour_rgb *rgb2)
r = rgb1->r - rgb2->r;
g = rgb1->g - rgb2->g;
b = rgb1->b - rgb2->b;
- return (sqrt(r * r + g * g + b * b));
+ return (r * r + g * g + b * b);
}
/* Work out the nearest colour from the 256 colour set. */
int
colour_rgb_find(struct colour_rgb *rgb)
{
- double distance, lowest;
- u_int colour, i;
+ u_int distance, lowest, colour, i;
if (colour_rgb_256 == NULL)
colour_rgb_generate256();
colour = 16;
- lowest = INFINITY;
+ lowest = UINT_MAX;
for (i = 0; i < 240; i++) {
distance = colour_rgb_distance(&colour_rgb_256[i], rgb);
if (distance < lowest) {