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Does Unity use non-linear interpolation for bone animation?

Discussion in 'Formats & External Tools' started by manuelflara, Nov 28, 2007.

  1. manuelflara

    manuelflara

    Joined:
    Jan 21, 2007
    Posts:
    87
    My artist complains about Unity distorting some of its animations bone movement. They actually play different from MS3D than from inside Unity. He thinks MS3D uses linear interpolation between frames and Unity uses something else. Is this true? Can this be changed anywhere?

    Thanks,
     
  2. Talzor

    Talzor

    Joined:
    May 30, 2006
    Posts:
    197
    Try to disable keyframe resuction in the import settings. I know our animator does that as the reduction causes small impressisions in the animations (feet starts to slide around a little etc.)
     
  3. Joe ByDesign

    Joe ByDesign

    Joined:
    Oct 13, 2005
    Posts:
    841
    Seeing this here as well. In Maya, the feet in the FBX are locked and do not move...

    In Unity they slide around. It doesn't seem to matter if Keyframe Reduction is used or not.

    It's very frustrating...
     
  4. Joachim_Ante

    Joachim_Ante

    Unity Technologies

    Joined:
    Mar 16, 2005
    Posts:
    5,203
    Unity uses hermite spline interpolation. We import animation by sampling the Maya animation at 30 frames per second, then run a filter on it to reduce the keyframes. As has been said, try turning off keyframe reduction. If that doesn't help Report a bug and send in a .mb / fbx file that clearly shows the issue.
     
  5. Joe ByDesign

    Joe ByDesign

    Joined:
    Oct 13, 2005
    Posts:
    841
    Thanks for the info Joachim. I'm still seeing feet sliding even with Keyframe Reduction off.

    Sent repro package as bug #17211.
     
  6. Stick

    Stick

    Joined:
    Dec 14, 2007
    Posts:
    37
    Hey Joachim. I was talking to Amir at the Austin Conference just a couple days ago about the keyframe reduction and animation importing features of Unity. For the games we are working on it would be very helpful to be able to control the sample rate and the filtering option to gain the right compression we are looking for. Since animations are one of the greatest areas of filesize growth in 3d assets, being able to control compression for them would be ideal for web based games. Is that a possibility?
     
  7. llavigne

    llavigne

    Joined:
    Dec 27, 2007
    Posts:
    977
    As well as offering different interpolation functions such as auto-plateau and other intelligent curve fitting techniques
     
  8. holmeren

    holmeren

    Joined:
    Dec 12, 2006
    Posts:
    300
    We have the same slide problem but it is fixed here by using the FBX (Max) key reduction and not Unitys. It increases the webplayer by 1 mb for two characters ;)