There's two ways you can do this: a true 3D engine that is "lock stepped" in perfect increments to a world grid (you need your entire level- all walls, doors, and objects- perfectly snapped to this world grid as well), or you can fake the whole thing with 2D graphics. You need to start by deciding which method you are going to use.
FYI- I have a 2D version of an engine like this with walls pre-rendered in Studio Max and I think it looks better than other realtime 3D versions. Just depends on your Studio Max abilities.
The 3D method should be straight forward if you know 3D engine concepts. The 2D version requires you to pre-render every individual wall section (blocks) in advance and then code a sorting engine to draw the wall sections according to your map data, from furthest to closest to the player's square, sorta like a depth-buffer. An optimized engine would know what wall section blocks are hidden so you don't waste time drawing them. I don't have any links to send you to, but I was able to come up with something nice in 2-3 days. It's not terribly hard.
FYI- I have a 2D version of an engine like this with walls pre-rendered in Studio Max and I think it looks better than other realtime 3D versions. Just depends on your Studio Max abilities.
The 3D method should be straight forward if you know 3D engine concepts. The 2D version requires you to pre-render every individual wall section (blocks) in advance and then code a sorting engine to draw the wall sections according to your map data, from furthest to closest to the player's square, sorta like a depth-buffer. An optimized engine would know what wall section blocks are hidden so you don't waste time drawing them. I don't have any links to send you to, but I was able to come up with something nice in 2-3 days. It's not terribly hard.