<html xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=utf-8"><meta name=Generator content="Microsoft Word 15 (filtered medium)"><style><!--
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--></style></head><body lang=EN-US link=blue vlink="#954F72"><div class=WordSection1><p class=MsoNormal>I think we should get together on the phone and discuss. Let’s try and use the web3d conf line sometime. Wed at 5 pacific or Mondays at 3 has worked. </p><p class=MsoNormal>Each vertex of a skin has to be bound to the appropriate skeleton parts. </p><p class=MsoNormal>Thanks and Best, </p><p class=MsoNormal>Joe</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Sent from <a href="https://go.microsoft.com/fwlink/?LinkId=550986">Mail</a> for Windows 10</p><p class=MsoNormal><o:p> </o:p></p><div style='mso-element:para-border-div;border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal style='border:none;padding:0in'><b>From: </b><a href="mailto:andreasplesch@gmail.com">Andreas Plesch</a><br><b>Sent: </b>Monday, November 26, 2018 10:37 AM<br><b>To: </b><a href="mailto:michalis.kambi@gmail.com">Michalis Kamburelis</a><br><b>Cc: </b><a href="mailto:x3d-public@web3d.org">X3D Graphics public mailing list</a><br><b>Subject: </b>Re: [x3d-public] HAnim and glTF skins</p></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I figured out by now that these fields were added for HAnim 2.0</p><p class=MsoNormal>whereas X3D V3.3 uses HAnim 1.0 .</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I think the idea is that you have a skeleton of joints with animation</p><p class=MsoNormal>data designed for it but the actual initial geometry is designed for</p><p class=MsoNormal>another initial state (pose). Then you can either redo the skeleton</p><p class=MsoNormal>and animation, redo the geometry, or apply a first ('binding')</p><p class=MsoNormal>transform to get the geometry into the state expected by the animated</p><p class=MsoNormal>joint transforms. This first transform would be defined by the</p><p class=MsoNormal>jointBinding fields, or as an inner joint in the skeleton's joint</p><p class=MsoNormal>hierarchy.</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I think these fields are similar to glTF's inverseBindingMatrix which</p><p class=MsoNormal>is also defined for each joint, and is applied to initial vertex</p><p class=MsoNormal>positions. So in order to play glTF skinned animations, it would make</p><p class=MsoNormal>more sense to implement these fields rather than finding a singular</p><p class=MsoNormal>solution.</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>It is unclear to me how skinCoord and skinBindingCoord interrelate,</p><p class=MsoNormal>and why non-humanoids are supposed to use those. Probably because it</p><p class=MsoNormal>is common to have this initial binding step rather than compatible</p><p class=MsoNormal>skeletons and geometry in the first place.</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Hopefully somebody can correct all the mistakes and misunderstandings</p><p class=MsoNormal>just offered above :)</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>-Andreas</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>_______________________________________________</p><p class=MsoNormal>x3d-public mailing list</p><p class=MsoNormal>x3d-public@web3d.org</p><p class=MsoNormal>http://web3d.org/mailman/listinfo/x3d-public_web3d.org</p><p class=MsoNormal><o:p> </o:p></p></div></body></html>