Call of Duty 4: .vision file
Create a new file in '[root]/raw/vision/' (create the 'vision' directory if it doesn't yet exists) called [mapname].vision, ignore any warnings that may come up when you save it with an unknown extension.
Open the .vision file you just created using Notepad, and copy-paste one of these and modify it to your needs.
Save it, and update your zone file with the following line:
rawfile,vision/[mapname].vision
The vision file should now be in effect.
You can find a copy of all stock vision file Here