Fun micro-optimisations.

This commit is contained in:
Michael Drake 2013-02-12 21:16:30 +00:00
parent 15e61743a3
commit 13574018d1

View File

@ -31,38 +31,32 @@
/* Darken a colour by taking three quarters of each channel's intensity */
#define darken_colour(c1) \
((((3 * ((c1 >> 16) & 0xff)) >> 2) << 16) | \
(((3 * ((c1 >> 8) & 0xff)) >> 2) << 8) | \
(((3 * ( c1 & 0xff)) >> 2) << 0))
((((3 * (c1 & 0xff00ff)) >> 2) & 0xff00ff) | \
(((3 * (c1 & 0x00ff00)) >> 2) & 0x00ff00))
/* Darken a colour by taking nine sixteenths of each channel's intensity */
#define double_darken_colour(c1) \
((((9 * ((c1 >> 16) & 0xff)) >> 4) << 16) | \
(((9 * ((c1 >> 8) & 0xff)) >> 4) << 8) | \
(((9 * ( c1 & 0xff)) >> 4) << 0))
#define double_darken_colour(c1) \
((((9 * (c1 & 0xff00ff)) >> 4) & 0xff00ff) | \
(((9 * (c1 & 0x00ff00)) >> 4) & 0x00ff00))
/* Lighten a colour by taking three quarters of each channel's intensity
* and adding a full quarter
*/
/* Lighten a colour by taking 12/16ths of each channel's intensity
* and adding a full 4/16ths intensity */
#define lighten_colour(c1) \
(((((3 * ((c1 >> 16) & 0xff)) >> 2) + 64) << 16) | \
((((3 * ((c1 >> 8) & 0xff)) >> 2) + 64) << 8) | \
((((3 * ( c1 & 0xff)) >> 2) + 64) << 0))
(((((3 * (c1 & 0xff00ff)) >> 2) + 0x400040) & 0xff00ff) | \
((((3 * (c1 & 0x00ff00)) >> 2) + 0x004000) & 0x00ff00))
/* Lighten a colour by taking nine sixteenths of each channel's intensity and
* adding a full intensity 7/16ths */
/* Lighten a colour by taking 9/16ths of each channel's intensity
* and adding a full 7/16ths intensity */
#define double_lighten_colour(c1) \
(((((9 * ((c1 >> 16) & 0xff)) >> 4) + 112) << 16) | \
((((9 * ((c1 >> 8) & 0xff)) >> 4) + 112) << 8) | \
((((9 * ( c1 & 0xff)) >> 4) + 112) << 0))
(((((9 * (c1 & 0xff00ff)) >> 4) + 0x700070) & 0xff00ff) | \
((((9 * (c1 & 0x00ff00)) >> 4) + 0x007000) & 0x00ff00))
/* Blend two colours by taking half the intensity of each channel in the first
* colour and adding them to half the intensity of each channel in the second
* colour */
#define blend_colour(c0, c1) \
(((((c0 >> 16) & 0xff) + ((c1 >> 16) & 0xff)) >> 1) << 16) | \
(((((c0 >> 8) & 0xff) + ((c1 >> 8) & 0xff)) >> 1) << 8) | \
(((( c0 & 0xff) + ( c1 & 0xff)) >> 1) << 0)
(((((c0 & 0xff00ff) + (c1 & 0xff00ff)) >> 1) & 0xff00ff) | \
((((c0 & 0x00ff00) + (c1 & 0x00ff00)) >> 1) & 0x00ff00))
/* Choose either black or white, depending on which is furthest from the
* percieved lightness of the supplied colour, c0. */