HRay main program, which contains the main function
intended for usage with the other modules in the HRay package
author: Kenneth Hoste, 2004-2005
part of a masters thesis at the University of Ghent, Belgium
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> import HRayOutput (getRenderTime, createPPM, getImage)
> import HRayParser (RenderDescr(RenderDescr), readDescr)
> import System.CPUTime (getCPUTime)
> import System.Directory (doesFileExist)
> import System.Environment (getArgs)
main function
> main :: IO()
> main = do args <- getArgs
> if (length args /= 2)
> then error "Usage: HRay