68 lines
2.5 KiB
Groff
68 lines
2.5 KiB
Groff
.\" $NetBSD: intro.4,v 1.5 2003/08/07 16:44:28 agc Exp $
|
|
.\"
|
|
.\" Copyright (c) 1980, 1993
|
|
.\" The Regents of the University of California. All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\" 3. Neither the name of the University nor the names of its contributors
|
|
.\" may be used to endorse or promote products derived from this software
|
|
.\" without specific prior written permission.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" @(#)intro.4 8.1 (Berkeley) 6/4/93
|
|
.\"
|
|
.sh 1 "Cursor Movement Optimizations"
|
|
.pp
|
|
One of the most difficult things to do properly is motion optimization.
|
|
After using
|
|
.Fn gettmode
|
|
and
|
|
.Fn setterm
|
|
to get the terminal descriptions,
|
|
the function
|
|
.Fn mvcur
|
|
deals with this task.
|
|
It usage is simple:
|
|
simply tell it where you are now and where you want to go.
|
|
For example
|
|
.(l
|
|
mvcur(0\*,0\*,LINES/2\*,COLS/2);
|
|
.)l
|
|
.lp
|
|
would move the cursor from the home position (0\*,0)
|
|
to the middle of the screen.
|
|
If you wish to force absolute addressing,
|
|
you can use the function
|
|
.Fn tgoto
|
|
from the
|
|
.b termlib (7)
|
|
routines,
|
|
or you can tell
|
|
.Fn mvcur
|
|
that you are impossibly far away,
|
|
For example,
|
|
to absolutely address the lower left hand corner of the screen
|
|
from anywhere
|
|
just claim that you are in the upper right hand corner:
|
|
.(l
|
|
mvcur(0\*,COLS\-1\*,LINES\-1\*,0);
|
|
.)l
|