public static Plane3D nullPlane3D()
{
Plane3D plane = new Plane3D();
plane.IsNull = true;
return(plane);
}
public static double CompareToPlane(AxisRectangle3D rect, Plane3D plane)
{
var behind = 0;
var infront = 0;
foreach (var v in new[] { rect.TopLeft, rect.TopRight, rect.BottomLeft, rect.BottomRight })
{
var cmp = plane.TestSide(v);
if (cmp < 0)
{
behind++;
}
else
{
infront++;
}
}
if (behind > 0 && infront > 0)
{
return(0);
}
if (behind > 0)
{
return(-1);
}
if (infront > 0)
{
return(1);
}
throw new ArgumentException("rect appears to be invalid");
}
public static bool TrianglePlane(Triangle3D t, Plane3D plane, out Line3D intersect)
{
var abLine = new Line3D(t.A, t.B);
var acLine = new Line3D(t.A, t.C);
var bcLine = new Line3D(t.B, t.C);
if (plane.IntersectLine(abLine, out var abIntersect))
{
if (plane.IntersectLine(acLine, out var acIntersect))
{
intersect = new Line3D(
abLine.PointAt(abIntersect),
acLine.PointAt(acIntersect));
return(true);
}
else if (plane.IntersectLine(bcLine, out var bcIntersect))
{
intersect = new Line3D(
abLine.PointAt(abIntersect),
bcLine.PointAt(bcIntersect));
return(true);
}
else
{
intersect = new Line3D();
return(false);
}
}
else if (plane.IntersectLine(bcLine, out var bcIntersect))
{
if (plane.IntersectLine(acLine, out var acIntersect))
{
intersect = new Line3D(
bcLine.PointAt(bcIntersect),
acLine.PointAt(acIntersect));
return(true);
}
else
{
throw new ArgumentException("triangle appears invalid");
}
}
else
{
intersect = new Line3D();
return(false);
}
}
public double Distance(Plane3D plane)
{
return(plane.Distance(this));
}
