'\" t
.\"     Title: EQN
.\"    Author: [see the "AUTHOR" section]
.\" Generator: DocBook XSL-NS Stylesheets v1.76.1 <http://docbook.sf.net/>
.\"      Date: 08/28/2023
.\"    Manual: BRL-CAD User Commands
.\"    Source: BRL-CAD
.\"  Language: English
.\"
.TH "EQN" "nged" "08/28/2023" "BRL\-CAD" "BRL\-CAD User Commands"
.\" -----------------------------------------------------------------
.\" * Define some portability stuff
.\" -----------------------------------------------------------------
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.\" http://bugs.debian.org/507673
.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.ie \n(.g .ds Aq \(aq
.el       .ds Aq '
.\" -----------------------------------------------------------------
.\" * set default formatting
.\" -----------------------------------------------------------------
.\" disable hyphenation
.nh
.\" disable justification (adjust text to left margin only)
.ad l
.\" -----------------------------------------------------------------
.\" * MAIN CONTENT STARTS HERE *
.\" -----------------------------------------------------------------
.SH "NAME"
eqn \- Allows the user to rotate the face of an ARB shape by providing the coefficients of an equation of the desired plane for the face\&.
.SH "SYNOPSIS"
.HP \w'\fBeqn\fR\ 'u
\fBeqn\fR {\fIA\ B\ C\fR} []
.SH "DESCRIPTION"
.PP
Allows the user to rotate the face of an ARB shape by providing the coefficients of an equation of the desired plane for the face\&. The coefficients
\fIA, B,\fR
and
\fIC\fR
are from the plane equation:
.PP

Ax + By + Cz = D
.PP
The user must be editing an
\fIARB\fR
shape and be rotating a face of the
\fIARB\fR
for this command to have any effect\&. When entering such a state, the user will be asked which of the face vertices should be held constant, and from this information the
\fID\fR
coefficient of the equation is determined\&.
.SH "EXAMPLES"
.PP
The example shows the use of the
\fBeqn\fR
command to rotate the face of the ARB being edited to be parallel to the
\fIxy\fR
plane\&.
.PP
\fBExample\ \&1.\ \&Rotate the face of an \fIARB\fR to be parallel to the \fIxy\fR plane.\fR
.PP
mged> \fBeqn 0 0 1\fR
.RS 4
The face of the
\fIARB\fR
is rotated to be parallel to the
\fIxy\fR
plane\&.
.RE
.PP
\fBExample\ \&2.\ \&\fR
.PP

.PP

.SH "AUTHOR"
.PP
BRL\-CAD Team
.SH "BUG REPORTS"
.PP
Reports of bugs or problems should be submitted via electronic mail to
devs@brlcad\&.org
