root/misc/wave.c

/*
* Wed Mar 22 04:08:39 CET 2006
* gcc -lm wave.c
* AlpT
*/

#include <math.h>
#include <unistd.h>

#define PI 3.1415926532

int main(int argc, char **argv)
{
        float x, y, s, count;
        int e, w, wo;
        char c, cn;

        c = argc > 1 ? argv[1][0] : '>';
        cn = argc > 2 ? argv[2][0] : '<';
        w = argc > 3 ? atoi(argv[3]) : 4000;
        wo=w;

        count=0;
loop:
        for(x=0; x<2*PI; x+=0.03) {
                y=sin(x)*40;

                s=y-1+40;
                for(e=0; e<s; e++)
                        printf(" ");
                if(y<0)
                        printf("%c", cn);
                else
                        printf("%c", c);
                
                printf("\n");
                usleep(w);
        }
        
        count+=1;
        w+=sin(count)*(wo>>2);
        if(count >= 2*PI)
                count=0;
                        
        goto loop;
}