void clip_box(double x1, double y1,
double x2, double y2)
{
reset();
m_VectorClipper.clip_box(m_VectorClipper.upscale(x1), m_VectorClipper.upscale(y1),
m_VectorClipper.upscale(x2), m_VectorClipper.upscale(y2));
}
