which collision detection method should I use?

[Kommi]

I am trying to implement iso type collision detection. Basically iso tiles that collide with each other. The following pic shows what I mean :
http://www.angelfire.com/clone/wolfbane/demo.jpg
Image that the yellow tile is a character that is moving down the hallway who's walls are the red tiles. The yellow tile should be able to move up against the red but not past. The method I am currently trying to implement is to have the iso tiles in rectangle bounding boxes and use a bitmask for pixel level collision detection. I was wondering if this was a good (practical approach)? Is there a better way? If so please describe.  

[kevglass]

Its an interesting way I hadn't thought of

If the world is really a 2d level, e.g. although its displayed isometrically the level is actually designed on the x-y plane you could do your collision data against your tile data instead of the actual pixels?

Kev

[Kommi]

Never mind I figured out a much better way by comparing the bounding box's midpoints.