PBOX                                                               Menu: PRISM
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Creates a solid rectangular prism or a rectangular (2D) polygon, given base
plane, dimensions and height.

        1. * (CHAR) plane of base rectangle (x-xy, y-yz, z-zx) <x>
        2. * (POINT) starting point
     for options `x' or `z':
        3. * (NUM) length on x
     for option `y':
        3. * (NUM) length on y
     for option `x':
        4. * (NUM) length on y
     for options `y' or `z':
        4. * (NUM) length on z
     for option `x':
        5. * (NUM) height of prism
     for options `y' or `z':
        5. * (NUM) length of prism
     for all options:
        6. * (Y/N) positive prism? <y>

Description:
This command creates a rectangular (2D) polygon or a solid rectangular prism
based on that polygon.
Specify the base plane (x  xy plane, the default; y yz plane, z xz plane) and
define the starting point of the base rectangle. Then enter the dimensions
along the x and y axes (for `x' option), or along the y and z axes (for `y'
option), or along the x and z axes (for `z' option). Specify the height (for
`x' option) or the length (for `y' and `z' options) (you may enter `0' for
a 2D polygon). Specify whether the solid is to be positive (`y' option) or
negative (`n' option).
You are prompted to create more solid prisms until you select another command.

         Example: \pbox x 0 0 0 4 7 3 y

Result: A box is created with its lower-left corner at the point 0 0 0. It is
4 units long in the x direction, 7 in the y direction, and 3 in the z
direction.
