i guess you mean minX, maxX...ect. is undefined...
but heres the function
void tri2d :: findMinMaxPts ( int & minX, int & maxX, int & minY, int & maxY, point2d * pts )
{
minX = ( int ) pts[ a ].x;
maxX = ( int ) pts[ a ].x;
if( pts[ b ].x < minX )
minX = ( int ) pts[ b ].x;
if( pts[ b...