   How to do iso-walls
  I am currently implementing isometric rendering in my engine. Though I was wondering how to handle walls. They could be part of the tile set. Disadvantage then ofcourse is that objects can not get behind the wall, or walk though a door area in that wall. Another method would be do make another layer on top for the walls, which seem like a good solution, however there still needs to be made an algorithm which detects a complete wall, to render it transparently when the player or an NPC is behind it. Although I think that I could get the last working, I would like to know how you think about this and if anyone with more experience can tell me how (s)he would do this. Thanks!   
  Consider each isometric cell to be a cube or a tall box in 3D space. The walls, then, become the sides of the box, like so:In a 3D implementation, it becomes a trivial matter to perform proper object clipping. 2D implementations get a bit trickier, since you need to represent each side of the cube by a screen-aligned bitmap rectangle, and that presents clipping issues since the 3D shape/region information of the wall is distorted, and the renderer 'sees' it as a billboard rectangle, so it may improperly clip with other billboarded rectangle objects. Of course, personally, I consider anyone who still does 'traditional' 2D isometric (at least on modern PCs) to be in a state of gross sin and in need of severe castigation. [wink]   ;  Damn good thing we don't care what you think about it then. I not only do it the old way, I'm using bitblt instead of 3d hardware!   ;  JTippetts method is a very simple and easy solution to use, but it requires 3D hardware. If you want to stick with 2D you could try a topic CrazyMike and EDI posted a few years ago. EDI named the algorithm LORM; Large Object Rendering Method.   ;  Thanks for the explanation. I do use opengl for the rendering and thus could use the method presented by JTippetts. Though this method does make it easier to add elevation to the maps, I am trying not to do that and keep it really a flat 2D game engine. The same method might still apply by addigng overlays for the wall.O-san: the page you linked was an interesting read. I definitely can learn from this!   