Line Properties 
The Line type exposes the following members.
Name  Description  

BoundingBox 
Gets the line's 3d axis aligned bounding box.
 
Direction 
Gets the direction of this line segment.
The length of the direction vector equals the length of
the line segment.
 
From 
Start point of line segment.
 
FromX 
Gets or sets the X coordinate of the line From point.
 
FromY 
Gets or sets the Y coordinate of the line From point.
 
FromZ 
Gets or sets the Z coordinate of the line From point.
 
IsValid 
Gets a value indicating whether or not this line is valid.
Valid lines must have valid start and end points.
 
Length 
Gets or sets the length of this line segment.
Note that a negative length will invert the line segment without
making the actual length negative. The line From point will remain fixed
when a new Length is set.
 
To 
End point of line segment.
 
ToX 
Gets or sets the X coordinate of the line To point.
 
ToY 
Gets or sets the Y coordinate of the line To point.
 
ToZ 
Gets or sets the Z coordinate of the line To point.
 
UnitTangent 
Gets the tangent of the line segment.
Note that tangent vectors are always unit vectors.
 
Unset 
Gets a line segment which has Unset end points.
