(June 22, 2018)
Propper is a modified version of VBSP with the unique feature of outputting a model instead of a BSP file. This allows mappers to create props out of brushwork, for optimization, skirting around engine limits, and so on.
The process of creating a model using Propper is simple: create brushwork as usual, tie the brushwork to a
propper_model entity, fill out the keyvalues of the
propper_model entity, setting values that would normally be set in the QC file of the model, create an optional physics mesh, and compile. For each
propper_model found in the map, a new model will be created and output to the
models directory of the game or mod it was compiled for. Alternatively, one can set Propper to export the model in OBJ format, allowing brushwork to be imported into 3D modeling packages.
(Thanks to MrFloyd for letting us demonstrate with his model.)
This version of Propper has been updated for use with Source SDK Base 2013, meaning it will work correctly with post-SteamPipe games. To install, extract the Propper executable and the FGD file into the
bin directory of the game you're mapping for, add the FGD in Hammer's Game Configurations menu, and set up Propper as an advanced compile configuration. (As Propper is merely a modified version of VBSP, it can also be invoked directly from the command-line or in batch files.)
For archival reasons, the last official version of Propper (which was released before SteamPipe) is also available below. Be warned that it will not work without a workaround using Source SDK Base 2007.