Often, you will hear casual references to worldspawn with GTK, but few times people actually explain what it is. Here I will clarify.
Worldspawn is the first entity listed in your .MAP. It is the first entity listed in any map, as it contains all the brush coordinate information that gives your map its architecture. As far as what you need to know it contains all the global settings for your map.
To access worldspawn, select a brush(not an entity), and then press the N Key to bring up the entity window. From worldspawn, you can set music, change the gravity, and a variety of BSP options.
I will go over some of the common options which you can use for the worldspawn.


message : text to print while loading the map. Used for name of level and designer name
typical usage: uptown by battlecow (all letters will be converted to Uppercase)


music : path/name of looping .wav file used for levelwide music (eg. music/delirium/noise.wav)
typical usage: This shouldn't get used. unless your creating a fun map of some sort you should use target_speaker's for your sounds. If you do happen to use this I recommend not such a loud noise as it's quite irritating to hear while playing.


_color : RGB value for ambient light color, default is 1 1 1 (White) I mix this with _minlight for test maps. another way to set the color, is while your selecting a normal brush, press 'k' and select your color from there.
typical usage: None, unless your using _minlight or _ambient


gravity : gravity of level (default is normal gravity: 800(shouldn't be messed with)).
typical usage: none, I recommend not using this as the server can set the gravity


enablePrecip : Toggling rain/snow on your map. Sprites fall from the skybox and through entities
typical usage: 0 - none(default), 1 - rain, 2 - snow


globalfog : Used with the new IObumpy.exe, you can tune it using r_fogdensity in /devmap
typical usage: 0.7 0.7 0.7 0.00002 Key: (Red, Green, Blue, density(1 means you cant see))


gridsize : granularity of the lightgrid created by q3map. Value is three integers separated by spaces, representing number of units between grid points in X Y Z. Default gridsize value is 128 128 256. Use larger powers of 2 to reduce BSP size and compile time on very large maps.
typical usage: default value is _ok_ , on jump maps to reduce compile time I recommend using 256 256 512 or 512 512 1024 ;) but if you want to do a longer nice compile use 32 32 64 or 64 64 128. MAKE SURE YOU KEEP THE VALUES TO POWERS OF 2


_blocksize : q3map always splits the BSP tree along the planes X=_blocksize*n and Y=_blocksize*n. Default _blocksize value is 1024. Increase the blocksize using larger powers of 2 to reduce compile times on very large maps with a low structural brush density.
typical usage: default is fine, when doing larger open maps try 2048 to reduce compile time MAKE SURE YOU KEEP THE VALUES TO POWERS OF 2, smaller maps can use 512 and Jump maps using hollowed boxes and teleporters should use 0 to remove all default splits.


_minlight : Minimum light value, levelwide. Uses the _color key to set color. Does not add unlike ambient.
typical usage: Test maps or small values like 0-20 (combined with sunlight/shader light) anything more looks out of place.


_mingridlight : Minimum lightgrid (dynamic entity lighting) levelwide.
typical usage: this refers to player model/weapon lighting (correct me if I'm wrong) Values like 50 are recommend if its a darker map increase by 25ish. 100 seems to be the maximum value.


_keeplights : Keep light entities in the BSP. Normally stripped out by the BSP process and read from the .map file by the lighting phase.
typical usage: set to 1 to keep all light entities used in your map, I recommend this if you plan on letting people learn from your map.


_lightmapscale : Floating point value scaling the resolution of lightmaps on brushes/patches in the world. Can be overridden in func_group (or other entities) (default 1.0).

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Copyright © 2009 Steven "Delirium" Krzanich. This document is released under the terms of the Creative Commons Attribution-Share Alike 3.0 Unported License, http://creativecommons.org/licenses/by-sa/3.0/