Re: [Haskell-cafe] Line drawing algorithm

Thanks Neil ...

Are you doing this to learn Haskell, learn about drawing lines, or to just get it implemented? If either of the latter two, when drawing a straight line you shouldn't need to do floating point operations such as this:

Actually, my reasons are first and third.

newY = y1 + round (slope * (fromIntegral (newX - x1)))

http://rosettacode.org/wiki/Bresenham%27s_line_algorithm#Haskell

Thanks for the link.

As to how to cope with the dy > dx case in your code given the dx > dy case, you could just swap the x and y coords at the start, then swap back the x and y coords of all the output points afterwards. Odd, but effective :-) Slope would differ right for both case right?

Regards, Kashyap