private static void NegativeNearClippingHelper(double near_dist, double far_dist, ViewportInfo vp)
{
double n = near_dist;
double f = far_dist;
double min_near_dist = 0.000100;
if ( double.IsNaN(min_near_dist) || min_near_dist < 1.0e-6 )
min_near_dist = 1.0e-6;
if ( vp.IsParallelProjection && n < min_near_dist )
{
// move camera back in ortho projection so everything shows
double d = 1.00001*min_near_dist - n;
if ( d < 0.005 )
d = 0.005;
n += d;
f += d;
if ( double.IsNaN(d)
|| d <= 0.0
|| double.IsNaN(n)
|| double.IsNaN(f)
|| n < min_near_dist
|| f <= n
)
{
// Just give up but ... refuse to accept garbage
n = 0.005;
f = 1000.0;
}
else
{
Rhino.Geometry.Point3d new_loc = vp.CameraLocation + d*vp.CameraZ;
vp.SetCameraLocation( new_loc );
}
near_dist = n;
far_dist = f;
}
}
