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tris in video game models?

polycounter lvl 12
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Rockley Bonner polycounter lvl 12
I know for high res sculpting you would use quads but could you use tris in an animatable mesh or would that be onely in meshes that dont animate?

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  • sprunghunt
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    sprunghunt polycounter
    once you export something into a game engine it becomes all tris. Quads are only a convenience for editing a model. So don't be afraid to just use tris when you need to.
  • dr jekyll
    One concern I have with tris is the winding order ( even if it's all tris in the engine how important is winding order to engine efficiency? ) Am I likely to break a feature or affect performance choosing right over left? Is there a general preference to have a model be compatable with most pipelines ( uv winding issues? skinning issues? tri strip breaking? )

    Has anyone ever been mandated one way over the other? Or is it just expected that artist are not tech savvy enough to know how to change the winding order? ( a simple mesh attribute in Maya )
  • sprunghunt
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    sprunghunt polycounter
    dr jekyll wrote: »
    One concern I have with tris is the winding order ( even if it's all tris in the engine how important is winding order to engine efficiency? ) Am I likely to break a feature or affect performance choosing right over left? Is there a general preference to have a model be compatable with most pipelines ( uv winding issues? skinning issues? tri strip breaking? )

    Has anyone ever been mandated one way over the other? Or is it just expected that artist are not tech savvy enough to know how to change the winding order? ( a simple mesh attribute in Maya )

    Well that depends on how the game engine interprets a model. Pre-set winding order and tri stripping could be thrown out by the import/export process altogether.

    In practical terms I know that when models were very low polygon tri-strips and so on were very important. Since you could make a huge difference to the number of strips with a small change. Renderware, for example, had a tri-strip view mode to debug this.

    However for current console platforms the performance impact of tri-strips isn't as important. They still exist but your control over them isn't likely to cause a large problem.

    It's still a good idea to avoid having uneven polygon distribution, triangle fans, or long and thin polygons. Mostly because these tend to deform poorly or cause visual issues.
  • dr jekyll
    Even without tri-strip as a concern...
    Does anyone know of ANY considerations when it comes to winding order and final path to the engine?
    Are you allowed to use any winding order you please?
    I am trying to convince my friend to release some awesome tools but he is hesitant because he is concerned that it might introduce topology concerns to pipelines unknowingly. Personally, I do not see where it makes a difference if winding order is broken as long as normal direction remains correct?
  • Mark Dygert
    It is also helpful when skinning to have loops and rings instead of tris whenever possible.
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