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#include "plplot.h"
/* Determines if point (px,py) lies above the line joining (sx1,sy1) to */
/* (sx2,sy2). It only works correctly if sx1 <= px <= sx2 */
int plabv(px, py, sx1, sy1, sx2, sy2)
int px, py, sx1, sy1, sx2, sy2;
{
int above;
if (py >= sy1 && py >= sy2)
above = 1;
else if (py < sy1 && py < sy2)
above = 0;
else if ((double)(sx2-sx1) * (py-sy1) > (double)(px-sx1) * (sy2-sy1))
above = 1;
else
above = 0;
return((int)above);
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.