help with understanding multiple models

laperen

ive been doing alot of low polygon modeling, all of which are essentially only using 1 mesh only

but how do the game developers switch the equipment of a character in the game?

an example of what i mean is in a generic RPG, i want to equip a sword.
from what i understand, for weapons it is simply parented to the joint most of the time, that is rather simple

for me THE PROBLEM is things like armor and clothing. all i know is that the character model is in pieces

is it multiple meshes using the same skeleton?

changing of head shapes, body shapes, shoes etc
does the animator reuse the skeleton and bind the model to it?
are the meshes seperate files or all in the same file in layers?

the modelling/animating tool im using is maya
and the game engine in question is unity if that helps

hopes someone can help me clarify this

Mark Dygert

Typically in the game animation is not stored with the mesh(s), so you'll have:
- A reference file that contains the mesh and the skeleton
- Either one big animation file or several smaller ones that will plug into the reference in the game.

When you start adding interchangeable models like boots, weapons or armor typically there is a bone they attach to and you save that piece out as a separate reference file. So you might have a Maya file with all your pieces, organized how you like but you export different pieces based on the requirements set out by the game.

Normally your base model is divided up into chunks, legs, toros, arms, head or however its been designed. And when you make new sets of armor you're making replacement pieces. The trick is making sure the parts all work together, which can be exhausting to test and why a lot of games opt to do material swaps.

Also keep in mind that some engines/games allow people to color their gear. This is typically done by creating a mask for the material that defines where the colors can change.

Every game is different as to how the tech works, but typically you skin the armor to specific bones and weapons have attachment points such as on the back, on the hip or in the hand. In your weapon you place a bone (or whatever they use) where you want it to match up on the player model.

The whole thing requires quite a bit of planning and coordination so the whole team needs to have a clear vision of what is going on or it all falls apart pretty easily.

laperen

does that mean its soemthing like:

the model, eg a shirt, is seperate from the main skeleton, but has bones with the same name as the ones in the main skeleton? and the shirt is binded to those bones? or joints really not bones

Mark Dygert

Yea normally all the bones are exactly the same and come from one skeleton. You export different pieces and sections of the timeline animation to separate files for the engine to work with.

Some gear might have its own bones and animations that get attached to a specific spot on the main skeleton but that all depends on how the team works.

We can't really get into specifics because those would be defined by the people in the team, so I have to keep it loose and generalized.

What I've done in the past, (mind you I'm mostly a max user) is keep everything in one file, all the meshes get bound to the same skeleton and everything is organized in the layer manager. I then use the "export selected" feature to output only the pieces I have selected. I don't remember a export selected in maya so what I think people typically do is delete all but the pieces they want, export those pieces, then undo.

Either way some scripting and a proper export plug-in can go a long way in automating the exporting. Also having a way that artists can test it all out in game or in a model viewer helps quite a bit.

laperen

okay thanks alot for the information