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@arafatamim
Last active March 24, 2022 23:56
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/*
* "Donut math: how donut.c works" blog post by Andy Sloane:
* https://www.a1k0n.net/2011/07/20/donut-math.html
* Relevant video: https://www.youtube.com/watch?v=DEqXNfs_HhY
*/
#include <stdio.h>
#include <string.h>
#include <math.h>
#include <unistd.h>
int main() {
float A = 0, B = 0;
float i, j;
int k;
float z[1760];
char b[1760];
printf("");
for (;;) {
memset(b, 32, 1760);
memset(z, 0, 7040);
for (j = 0; j < 6.28; j += 0.07) {
for (i = 0; i < 6.28; i += 0.02) {
float c = sin(i);
float d = cos(j);
float e = sin(A);
float f = sin(j);
float g = cos(A);
float h = d + 2;
float D = 1 / (c * h * e + f * g + 5);
float l = cos(i);
float m = cos(B);
float n = sin(B);
float t = c * h * g - f * e;
int x = 40 + 30 * D * (l * h * m - t * n);
int y = 12 + 15 * D * (l * h * n + t * m);
int o = x + 80 * y;
int N = 8 * ((f * e - c * d * g) * m - c * d * e - f * g - l * d * n);
if (22 > y && y > 0 && x > 0 && 80 > x && D > z[o]) {
z[o] = D;
b[o] = ".,-~:;=!*#$@"[N > 0 ? N : 0];
}
}
}
printf("");
for (k = 0; k < 1761; k++) {
putchar(k % 80 ? b[k] : 10);
A += 0.00004;
B += 0.00002;
}
usleep(30000);
}
return 0;
}
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