P3D                                                                Menu: POLYG
==============================================================================
Creates a solid prism from the current polygon.

        1.   (Y/N) expand along z? <y>
     if reply is `y'
        2.   (NUM) height of polygon (on z-axis)
     if reply is `n'
        2.   (Y/N) expand current polygon ? <y>
        3.   (POINT) expand from point
        4.   (POINT) expand to point
     if reply to prompt 2 is `n'
        5. * (IND) polygon to expand
        6. * (Y/N) confirm choice
     for all options
        7.   (Y/N) create a POSITIVE solid? <y>

Description:
This command turns a polygon into a solid prism with two parallel identical
bases, one of which may be the current polygon. You are asked whether you wish
to expand the polygon parallel to the z axis (the default) or give
a displacement in space. If you require the former, you are prompted for
a single displacement value (height) along the z axis. If you wish to give
a displacement in space, you are first asked whether you wish to expand the
current polygon or a previously created one. You are then prompted for two
points (from and to).
The displacement of the new polygon from the original one is given by picking
two points (from and to). This displacement is maintained between every point
of the original polygon and the corresponding points on the new one. The
direction of the edges connecting the two bases is determined by the direction
from the "from" point to the "to" point.
If you wish to expand a polygon, other than the current one, you are asked to
indicate it and confirm its selection. You are prompted to select additional
polygons.
Answering the Y/N prompt with `y' creates a positive prism; `n' creates
a negative one.
If you attempt to execute the command on an open polygon, a system warning
appears:
! polygon is open, will fail \solid !

        Example: \p3d n y 10 10 0 15 15 10 y

Result: The current polygon is copied at a displacement of 5 units, 5 units
and 10 units in the x, y, and z directions respectively. The two bases of the
solid prism generated will be the active polygon and its copy. The prism will
be a positive one.
