To define a centerline, you specify a figure name, starting station, and starting point number.
If you use a point off the centerline to determine the beginning station, then a perpendicular line is established and that intersection is the starting station. Therefore, any point you use to establish the beginning station must be adjacent to some leg of the centerline.
CL IS [figure] (station) (point)
In the following example, the beginning of this command sequence describes how to draw the centerline figure.
BEGIN CL1
NE 1 1000 1000
NE 2 1000 1500
NE 3 1300 1700
END
NE 4 1100 1100
CL IS CL1 500 4
! Figure CL1 is the current centerline.
! Start Station: 400.00 End Station: 1260.56
Figure CL1 is the current centerline. Assigning Point 4 a station of 5+00 results in the centerline starting at station 4+00.
Centerline figure
CL IS [figure] (station) (point)
Parameter | Definition |
---|---|
figure | The figure that you want to use as the centerline. |
station | The defining station of the centerline. If you do not type a point number, then this is the station at the beginning of the figure. If you type a point number, then the station is at the point you specify. When you don't specify a station, the default 0+00 is used. |
point | An optional reference point for the station. The point specified need not be on the centerline, but it must be adjacent to the centerline (not beyond the end points). |