There are two methods of taking screenshots during the game. First you can
press ALT-PrintScreen to capture the current screen in the clipboard,
allowing you to exit GPL and paste it into the paint program of your choice.
Secondly, and useful if you want to take a number of different shots at
once, pressing just the PrintScreen button saves sequentially numbered PBF
files (gplss##.pbf) to your GPL directory. After exiting GPL you can then
use the included pbf2tga.exe program to convert them to a usable TGA format.
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all opinions expressed while drunk, stoned and flying through clouds.