################
omc-geometry.lsp
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Commands and functions for handling raw geometry.

********
Commands
********

LIST\-LEN
=========



ILP
===

Intersect line and plane. Draw a point in the intersection of a
line and a plane.

IPP
===

Intersect two planes. Draw a line in the intersection of two
planes.

ROUND\-LINE\-COORDS
===================

Round specified coordinates of the start and end points of lines to
a multiple of the specified divisor.

INVERT\-LINES
=============

Switch start and end points of the lines selected.

*********
Functions
*********

(**omc\-geometry\-v\+** *vector0* *vector1*)

   Return the sum of two 3d vectors.

(**omc\-geometry\-v\-** *point0* *point1*)

   Return the difference of two 3d vectors.

(**omc\-geometry\-sv\*** *scalar* *vector*)

   Multiply a scalar and a 3d vector.

(**omc\-geometry\-dot** *vector0* *vector1*)

   Return the dot-product of two 3d vectors.

(**omc\-geometry\-cross** *vector0* *vector1*)

   Return the cross-product u x v. Arguments are 3d vectors.

(**omc\-geometry\-norm** *vector*)

   Return the L2 norm of a 3d vector.

(**omc\-geometry\-intersect\-line\-plane** *point0\-in\-line* *point1\-in\-line* *point0\-in\-plane* *point1\-in\-plane* *point2\-in\-plane*)

   Return the point of where a line and a plane intersect.

(**omc\-geometry\-intersect\-plane\-plane** *point0\-in\-plane0* *point1\-in\-plane0* *point2\-in\-plane0* *point0\-in\-plane1* *point1\-in\-plane1* *point2\-in\-plane1*)

   Return two points on the line where two planes intersect.

(**omc\-geometry\-round** *num* *div*)

   Round number to a multiple of divisor. Round using half to even. See https://en.wikipedia.org/wiki/Rounding#Round_half_to_even

(**omc\-geometry\-test\-round**)

   

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Global variables
****************

* **precision** assigned in

   * *c:list\-len*

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Functions called on load
************************

* **princ**