vmf-api Licensed under the GNU GPL. This api is designed to help users build .vmf files, which are files read in by Valve's Source SDK Hammer World Editor. Hammer saves world info in .vmf files. When a world is completed, Hammer will then compile the .vmf file(s) into files that can be read by the Source Engine. .vmf files are formatted in a similar fashion to JSON. They consist of labels, with each individual label consisting of many parameters, which may be strings (text, integers, floats, etc.) or sub-labels. These sub-groups are designated by curly braces {}.