# FreeBSD Manual Pages

```3PTARB(nged)		     BRL-CAD User Commands		  3PTARB(nged)

NAME
3ptarb -	Build an ARB8 shape by extruding a quadrilateral through a
given thickness.

SYNOPSIS
3ptarb [arb_name] [x1] [y1] [z1]	[x2] [y2] [z2] [x3] [y3] [z3] [x/y/z]
[coord1] [coord2]	[thickness]

DESCRIPTION
Build an	ARB8 shape by extruding	a quadrilateral	through	a given
thickness. The arguments	may be provided	on the command line; if	they
are not,	they will be prompted for. The x1, y1, and z1 are the
coordinates of one corner of the	quadrilateral. x2, y2, z2, and x3, y3,
z3 are the coordinates of two other corners. Only two coordinates of
the fourth point	are specified, and the code calculates the third
coordinate to ensure all	four points are	coplanar. The x|y|z parameter
indicates which coordinate of the fourth	point will be calculated by
the code. The coord1 and	coord2 parameters supply the other two
coordinates. The	direction of extrusion for the quadrilateral is
determined from the order of the	four resulting points by the
right-hand rule;	the quadrilateral is extruded toward a viewer for whom
the points appear in counter-clockwise order.

EXAMPLES
The following are run from the MGED command prompt:

Example 1. 3ptarb example with BRL-CAD prompting	for information

mged> 3ptarb
Start the 3ptarb command.

Enter name for this arb:	thing
The new ARB8	will be	named thing.

Enter X,	Y, Z for point 1: 0 0 0
Point one is	at the origin.

Enter X,	Y, Z for point 2: 1 0 0
Point two is	at (1, 0, 0).

Enter X,	Y, Z for point 3: 1 1 0
Point three is at (1, 1, 0).

Enter coordinate	to solve for (x, y, or z): z
The code will calculate the z coordinate of the fourth point.

Enter the X, Y coordinate values: 0 1
The x and y coordinates of the fourth point are 0 and 1.

Enter thickness for this	arb: 3
The new ARB8	will be	3 units	thick.

Example 2. 3ptarb command as single line	input

mged>3ptarb thing 0 0 0 1 0 0 1 1 0 z 0 1 3

Same as above example, but with all arguments supplied on the command
line.

AUTHOR