ref: 86e0099835f99de6ccc3bee33a297387993aa037
dir: /sys/src/9/bitsy/gamma.c/
#include <u.h> #include <libc.h> #include <stdio.h> double gamma = 1.6; int remap5(int i) { double v; v = (double)i/31.0; return 31.0*pow(v, gamma); } int remap6(int i) { double v; v = (double)i/63.0; return 63.0*pow(v, gamma); } int remap(int i) { int r, g, b; b = i & 0x1F; g = (i>>5) & 0x3F; r = (i>>11) & 0x1F; return (remap5(r)<<11) | (remap6(g)<<5) | (remap5(b)<<0); } void main(void) { int i; printf("/* gamma = %.2f */\n", gamma); printf("ushort gamma[65536] = {\n"); for(i=0; i<65536; i++){ if((i%8) == 0) printf("\t"); printf("0x%.4x, ", remap(i)); if((i%8) == 7) printf("\n"); } printf("};\n"); }