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.\" Copyright (c) 1980, 1993
.\" The Regents of the University of California. All rights reserved.
.\"
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.\" modification, are permitted provided that the following conditions
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.\" @(#)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
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