The CURV Routine is used to establish the centre point and two tangent points of a circle, given two tangent lines, the IP
and the radius of the curve.
The required centre is entered under the unknown point and the two required TP's are entered under course B,
reference points 1 and 2. Tangent lines are defined by the IP under known point, course A, and a known point
on each tangent line under reference points 1 and 2 course A. Note that the required TP entered in reference point 1,
course B, will correspond to the line defined by reference point 1, course A. An example of CURV is shown below.
The known tangent lines are 125 to 101 and 101 to 102, and the radius is 120 metres.
The required centre point is point 130, and the two TP's are points 129 and 136.
Note the correspondence between the reference points.
This routine must be entered each time a set of points are fixed using this routine, i.e.
it does not support multiple entries.
XY Data Point Record Col
Record Type 02 1
Routine CURV 2
Unknown Point ____ 3
Course A - Known Point ____ 4
Bearing _______ 5
Code (P) _ 6
Distance __________ 7
Indicator _ 8
Point 1 ____ 9
Point 2 ____ 10
Course B - Known Point ____ 11
Bearing _______ 12
Code (P) _ 13
Distance __________ 14
Indicator _ 15
Point 1 ____ 16
Point 2 ____ 17
Auxiliary Point ____ 18