Why don't you use your own format ? A simple one which only contains what you use in your engine ? If you're going to write a collada parser, you could easily make it output the stuff you need in a compact / easy to read and use format then ^^
This would be easier to parse/load (and also faster since you can get rid of all the collada stuff you don't need, and god knows how much of that there is ^^)
That's the path im leaning towards since I can't find any collada parsers out there and I already have a script that handles geometry data and some material stuff.
My biggest concern is limiting graphics artists later down the road. I've never worked with a graphics artist before so I'm not sure if it is a big deal for them to follow a certain collada format or not. Any graphical artists out there care to comment on the difficulties of following a limited collada spec?
You WILL have to limit your graphists : the Collada format is so complex that you can't possibly write a parser that will cover everything your graphists will do. So in my opinion, you're better of writing your own exporter/parser.
I had the exact same problem in my previous work. We reached a point where we couldn't use the basic format we were using at the beginning (the DirectX .x format ^^) and we had to choose between
- using an existing format that would cover all our needs (present and in the near future at least)
- writing our own exporter
I ended up writing a Maya loader/exporter with a little custom file format. Note that we only used Maya, so I could directly use the Maya API and not bother with interop with other 3D softwares. If you're going to allow many different software, then the "custom expoter" approach won't work.
Anyway, I couldn't possibly write an exporter that could handle everything Maya does, so I had a lot of "brainstorming" with the graphists to understand what their needs were and would be. We decided on a workflow that was acceptable for both parts : simple enough for me to keep the exporter simple and flexible enough for them to work quickly / efficiently.
Once this part was done, it was quite simple. They had a documentation of what was supported, how to export various stuff, and if they needed something new, they'd simply asked (I usually answered by "you won't need this, it'll break ingame performances !" ^^)
So the moral : if you have a basic collada parser, continue to work on it, but you should find a graphist as soon as possible to discuss with him what will his needs be. And improve your parser accordingly, this is perfectly fine. Most graphists used to production will be used to following a certain workflow.
Also, don't simply ask him "send me a list of what you need" ... you'll end up writing a full Collada parser