Coordinates

Coordinates may be given explicitly as coordinate values. Planar Hull Modelling, however, also offers different possibilities for relative definition of coordinates.

There are two main ways of doing this:

1. Via references to principal planes in the ship, for example, at frame positions.

2. By reference to topology points.

In general a coordinate may look like:

<coord>::= <number> | <ref_term>

The layout of <ref_term> is similar in all cases but its prefix depends on the type of reference.

Here:

<ref_term>::= <plane_ref> | <point_ref>

The layout of these terms will be described in detail below.