void CXXXX::RotatePoint(float &x,float &y,float ang,float centerX,float centerY)
{
float a = ang * PI / 180;
float cs = (float)cos(a);
float sn = (float)sin(a);
float dx = x - centerX;
float dy = y - centerY;
x = centerX + dx * cs - dy * sn;
y = centerY + dx * sn + dy * cs;
}