[Haskell-cafe] Re: Wrapping FTGL in FFI calls

Jules Bean jules at jellybean.co.uk
Fri Jun 20 16:26:07 EDT 2008

Jefferson Heard wrote:
> Oh, and I should say the function I want to implement is
> getFontBBox :: Font -> String -> IO [Float]
> I do know how to marhsal/unmarshal the String.  Just not the CFloat 
> array to Haskell [Float]

import Foreign.C
import Foreign.Ptr
import Foreign.Marshal.Array

import Control.Applicative((<$>))

oneway :: Ptr CFloat -> IO [Float]
oneway p = map real2Frac <$> peekArray 4 p

the other way you would probably want withArray, but I think this is the 
way you need?

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