Converting Counter Strike 1.6 .bsp files to CS:GO Source SDK format

    In this post I will explain how to decompile GoldSrc .bsp map file and import it in the Hammer Editor for Source Engine. By following this tutorial you will learn how to easilly port your favorite 1.6 maps for Counter-Strike: Global Offensive.

    In my fy_iceworld_origins map I've used this method to get the original map’s architecture for my project. Valve Hammer editor supports several file formats, including .rmf and .map. After some testing, I realized that importing process should consist of 3 steps.

1. First step is decompiling original .bsp file and converting it into .map format. After several fails, I've found the utility, which does its job well. It is called BspTwoMap v1.4. Download it and after unpacking the archive just drag-and-drop your .bsp file on the .exe. The utility will automatically create .map file in its directory.
2. Second step. Unfortunately you can't just export your .map file straight into Source Hammer Editor, so we need this step to make all the things work. That is why we will convert our .map file into .rmf format. For doing this, we need to get the old Hammer Editor for GoldSrc engine. Just import your .map file in Hammer, save it as .rmf and we're done.
3. Final step. Open your .rmf file with Source SDK Hammer and you'll get something like this:

    As you can see, there are no textures on the map, the triggers and entities don't work properly, the brushes are sometimes fragmented and there are also quite many leaks. However the original maps geometry is preserved, so we can use it for further work.