CD Projekt RED has just released REDkit, its SDK and level editing tools for The Witcher 2, in open beta, enabling modders and indie developers to create content using the engine of the popular RPG.
The documentation in the wiki is still pretty sparse, but to judge from the video above, REDkit includes all of the functionality you’d expect – including a terrain editor and a forest-generation system powered by SpeedTree – and some you wouldn’t, including a built-in mesh editor and a node-based material editor.
The editor itself is free, but to use assets from the game, you’ll need to have a PC copy of the game itself, patched to version 3.3. It won’t work with the Steam edition.
There is also a separate file importer for 3ds Max 2009 and 3ds Max 2013.
Download REDkit (Registration required)