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/* This program is written by Henning Makholm, and is in the
* public domain.
*/
#define TEST_IMAGE_WIDTH 50
#define TEST_IMAGE_HEIGHT 50
#include <math.h>
#include <stdlib.h>
void
makepixel(int x,int y,int *r,int *g,int *b,int *a) {
double yy = 2*(double)y/(TEST_IMAGE_HEIGHT-1) - 1 ;
double xx = 2*(double)x/(TEST_IMAGE_WIDTH-1) - 1 ;
double rad = sqrt(xx*xx+yy*yy) ;
unsigned t = x + abs((y - TEST_IMAGE_HEIGHT/2)) ;
t = t / 10 + ((600 + y - TEST_IMAGE_HEIGHT/2) / 10)*77 ;
if( rad < 0.9 )
*a = 255 ;
else if( rad < 1 )
*a = 190 ;
else if( rad < 1.2 )
*a = 73 ;
else
*a = 0 ;
t *= 3847822 ;
t ^= 29938132 ;
t %= 2093847 ;
*r = 120 * ((t >> 3) % 3) + 3 ;
*g = 120 * ((t >> 7) % 3) + 3 ;
*b = 120 * ((t >> 10) % 3) + 3 ;
}
#include "mkbase.i"
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