From TDN

Note! You must have the Map2Dif exporter to use any of these programs to create DIF files! Currently Map2Dif is only availabe for windows.

Torque Game Engine DIF Exporter Matrix	QuArK	WorldCraft Hammer	3D World Studio	Torque Pipeline	Radiant	max2map	Game Level Builder	GameSpace (Digitalflux Version)	GameSpace (Caligari Version)	Blender[6]	Maya Level Tools	Deled
Application Version	6.3		5.40	1.1							5.0+	1.52+
Application Price	Free	[1]	$80	$12 [2]	free [2]	free [2]	$40 [2]	$20 [2]	$25 [2]	free [2]	free [2]	free\$15 [7]
Geometry/Export
Brush Modeling	yes	yes	yes	yes	yes	no	partial	no [4]	?	no	?	yes
.map Export	yes	yes	yes	yes	yes	partial	yes	yes	?	yes	?	yes
Integrate map2dif export	yes	yes	yes	yes	no	?	?	no	?	?	?	yes [7]
Lights & Entities
Lights	yes	yes	yes	yes	yes	no	partial	partial [5]	?	?	?	yes [8]
Preview Lightmaps	no	?	yes	no	?	no	?	?	?	?	?	yes
Custom Entities	yes	yes	yes	no	yes	no	yes	?	?	?	?
Optimization Tools
Portals	yes	yes	yes	yes	yes	no	?	yes	?	?	?	yes
Detail Brushes	yes	yes	yes	yes	yes	no	?	yes	?	?	?	yes
Levels of Detail (LOD)	yes	?	partial	partial	?	no	?	?	?	?	?	?
Optimization Tools	yes	?	no	no	?	?	?	?	?	?	?	no
Textures
Apply Materials	yes	yes	yes	yes	yes	no	yes	yes	?	yes	?	yes
Texgen Coordinates	yes	yes	yes	yes	yes	no	?	yes	?	?	?
TSE Light Brushes	no	no	yes	yes	yes	no	?	yes	?	?	?
Platforms Supported
GG Recommended Tool	yes	no	yes	yes	no	no	no	no	no	no	no	no
Windows	yes	yes	yes	yes	yes	yes	yes	yes	yes	yes	yes	yes
Mac OS X	no	no	no	no	partial [3]	no	no	no	no	yes	yes	no
Linux	no	no	no	no	yes	no	no	no	no	yes	yes	no

Footnotes:

• [1] WorldCraft/Hammer has been authorised by Valve for the use of Torque products (Free and Commercial), however, the actual EULA has not been changed in version 3.4 or 3.5 (beta).
• [2] GTKRadiant itself is GPL'd, it uses game assets from Q3 based games in its default configuration
• [3] Runs on Mac OS X under X11.
• [4] Includes tutorials on modelling convex polygons for interiors, and a library of convex shapes.
• [5] Omni light only.
• [6] Several map exporters have been developed for Blender, none is completely robust. Here are two of the most prominent: Benoit Touchette's Plugin, Jason Howard's Blend2Map.
• [7] DeleD Lite version is freeware, fixed size lighmap and content demo version exporter (export restricted 25 brushes).