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Hey there.

I've been fooling around with some map xml and have come up with a few questions that I hope you guys can answer. Please forgive me if these questions have been answered elsewhere, I had a brief search and didn't turn up anything.

1) Inverse floor / ceiling

On looking at the map file the Y values for ceilings are lower than those of the floor. Does the engine invert all Y values found in the map? Also - what is the difference between a floor and a ceiling in the context of the engine?

2) Wall misalignment

It seems possible to build a perfectly closed room with the editor, yet on reading the map file the walls seem to stop short 1 unit from meeting with the floor. Just curious as to why this is?

3) Primitives

Some objects have a primitive property with an ID. I assume that the ID points to a model or assembly of polys, and the co-ords written under are to do with the bounding box - but whereabouts is the data defining the shape of the primitive itself? Also - is there any benefit engine-wise from using primitives rather than loose polys, or is it simply for ease of use?

4) Normals

Is there a concept of normals in the engine or is every object considered double sided by default?

5) Sections

I've seen some maps where a large area of flat ground was split into multiple polygons instead of being left as one larger polygon. Are there any benefits to be had for this kind of splitting up of geometry? If so what what's the general rule of thumb as far as how big a poly can be before you split it?

Much appreciated if you can help me out with any of the above. Thanks in advance!
1) Floors detect collision downwards, ceilings upward. Watch out though, the new editor's pieces will all be the same. Wink

2) Forget why.... Sorry, can't help here.

3) Primitives are just for ease of use. Wink

4) Normals ARE used, if they weren't there would be no lighting. Wink But yes, all faces are double sided. Hopefully Brian will change this (map editing advantage)....

5) Breaking them up a little but not to much is good because if there's just one peice, it has to render the whole thing even when it's offscreen (or something like that), but when it's broken up it only has to render the ones that are partially on screen. Of course, breaking them up to much will slow it down. Rule of thumb? I just break peices up as needed for the map (to prevent T intersections, to keep everthing on a [uneven] grid, this helps the lighting ALOT).
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