On 17 June 2010 19:58, Stephen Tetley
Area, I'm not sure about. Maybe you **good** integrate the function through a space, but this might not be a good idea.
Ahem, swap 'good' for 'could' in that bit... Antony Courtney used a dual representation for his vector graphics program - Haven. Images were both a "colour characteristic function" and proper/plain characteristic function for regions. I think this was so that "point in polygon" calculations could be made easily. type Image = (Point -> Color, Region) Perhaps, it might not be too much of a stretch to model regions both with a characteristic function and a more concrete representation that allows area to be taken more easily. The region combinators would become more complicated though.