NAME
	vis

SYNOPSIS
	vis [OPTION]... BSPFILE

DESCRIPTION
	vis is a tool used in the creation of maps for the game Quake.
	vis looks for a .prt file by stripping the file extension from BSPFILE
	(if any) and appending ".prt". vis then calculates the potentially
	visible set (PVS) information before updating the .bsp	file,
	overwriting any existing PVS data.

	This vis tool supports the PRT2 format for Quake maps with detail
	brushes. See the qbsp documentation for details.

	Compiling a map (without the -fast parameter) can take a long time,
	even days or weeks in extreme cases. Vis will attempt to write a state
	file every five minutes so that progress will not be lost in case the
	computer needs to be rebooted or an unexpected power outage occurs.

OPTIONS
	-threads n     Set number of threads explicitly. By default vis will
	               attempt to detect the number of CPUs/cores available.

	-fast          Skip detailed calculations and calculate a very loose
	               set of PVS data. Useful for testing.

	-level n       Select a test level from 1 to 4. Increasing test levels
	               require more calculations, but compute a tighter PVS.
	               Finished maps should be compiled with -level 4.

	-v             Verbose output

	-vv            Very verbose output

AUTHOR
	Written by Kevin Shanahan (aka Tyrann)
	Based on source provided by id Software
	http://disenchant.net

REPORTING BUGS
	Please send bug reports to tyrann@disenchant.net.
	Improvements to the documentation are welcome and encouraged.

COPYRIGHT
	Copyright © 2013 Kevin Shanahan
	Copyright © 1997 id Software
	License GPLv2+:  GNU GPL version 2 or later
		<http://gnu.org/licenses/gpl2.html>.
	This is free software:  you are free to change and redistribute it.
	There is NO WARRANTY, to the extent permitted by law.

SEE ALSO
	qbsp, light, quake.