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/* Copyright (c) 1992 AT&T - All rights reserved. */
#include <libc.h>
#include <libg.h>
#include "libgint.h"
#include <math.h>
#define rad2deg(x) 180*((x)/3.1415926535897932384626433832795028841971693993751)
void
arc(Bitmap *b, Point p0, Point p1, Point p2, int v, Fcode f)
{
unsigned int d;
int x, y, r, start, end, delta;
GC g;
p1.x -= p0.x;
p1.y -= p0.y;
p2.x -= p0.x;
p2.y -= p0.y;
r = (int)sqrt((double)(p1.x*p1.x + p1.y*p1.y));
start = (int)(64*rad2deg(atan2(-p2.y, p2.x)));
end = (int)(64*rad2deg(atan2(-p1.y, p1.x)));
if(start < 0)
start += 64*360;
if(end < 0)
end += 64*360;
delta = end - start;
if(delta < 0)
delta += 64*360;
x = p0.x - r;
y = p0.y - r;
if(b->flag&SHIFT){
x -= b->r.min.x;
y -= b->r.min.y;
}
d = 2*r;
g = _getfillgc(f, b, v);
/*
* delta is positive, so this draws counterclockwise arc
* from start to start+delta
*/
XDrawArc(_dpy, (Drawable)b->id, g, x, y, d, d, start, delta);
}
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