My modelling practices (need advice)

[GrogMcGee]

I would assume that the source engine uses the pretty standard hierarchy for a file:


scene root
| | | |__ mesh object 1
| | |
| | |___ mesh object 2
| |
| |___ some other thing
|
|___ another thing


basically when you export the file from your application everything will be parented to a scene root of some kind. So it should be fine that the mesh is made up of different disconnect triangles.

However, the physics engine may treat the mesh as separate collisions in which case your box may fall apart the moment a force is applied to it.


Valve provide a lot mod community support for the source engine, as such you should be able to find people who are specifically into building models for the engine and tons of documentation - eg, http://developer.valvesoftware.com/wiki/Category:Modding
or http://www.google.ca/search?rlz=1C1GPMD_enCA311CA311&sourceid=chrome&ie=UTF-8&q=adding+a+model+to+source+engine


Overlapping parts is likely to be fine. However, you'll want to avoid having multiple faces occupying the exact same space, that'll likely cause flickering.

[Psyk0]

Some engines do not have a problem with open geometry but airtight meshes are usually best. Here's an example of airtight mesh, i've unwrapped the uv's into "modules" if you want to break the repetitive textures you can move another side to it's own UV space (only 2 sides are visible at the same time anyway).

http://www3.sympatico.ca/psykopat/lnkz/crate.jpg

Max 9 scene file + OBJ:
http://www3.sympatico.ca/psykopat/lnkz/crateexample.rar

[CrimsonGT]

Can you explain what you mean by multiple faces occupying the same space? (maybe draw an arrow to where I did that on my mesh)

[CrimsonGT]

Ah wow, very nice. It drives me nuts I cant figure out how to make a mesh "airtight". There just doesnt seem to be many good poly modelling tutorials for XSI, and I am having a hell of a time learning on my own. Thank you for the picture and obj file though, its nice to see how it should be.

*Edit*

After looking at your UV Map, that was another question I meant to ask earlier. So if multiple areas are the same size + shape (like each pillar and so on) you can make all 4 use one UV mesh space?

[GrogMcGee]

You can lay out UVs however you want them to be - they can overlap, be layered on top of eachother, etc.

Faces occupying the same space is just a thing to watch out for - I don't think (I also doubt that) that model had any.

This video appears to explain some basic poly modeling in XSI (http://guerrillacg.org/software-videos/xsi/96)

[Psyk0]

After looking at your UV Map, that was another question I meant to ask earlier. So if multiple areas are the same size + shape (like each pillar and so on) you can make all 4 use one UV mesh space?

Yes, that is quite common in older engines (in fact you can pick any uv shell and move it around, as long as it fits with the rest of the design!). For next gen titles not all engines support mirroring. The only drawback is that you loose some randomness, meaning each pillar will be an exact copy and so on. You can overcome some of the problem by moving / opposite mirroring your uv shells around. I have some space left in there too, i could pick the top of a pillar and scale it to fill in the empty space and that part would have it's own unique texture / detail compared to its identical counterparts. So in short, be efficient and be creative!

My modeling approach was really simple, make a box, connect edges to prepare the pillar extrusion, select faces that will make the pillars, extrude. Next i simply did a bevel on each sides / top. Finally an inset/extrude on the sides to create the nuclear logo thingie. Airtight meshes will have a higher triangle count than using open geometry, you have to decide in which situation it's worth using one method over the other or mix both. If polycount is too high i will go back and optimize. I could probably shave 32 tris off just by getting rid of the side bevels and let the textures give the impression there's a beveled surface.