Timeline for Skeletal animation: What is the purpose of multiplying interpolated bone matrix with parent's matrix?
Current License: CC BY-SA 4.0
6 events
| when toggle format | what | by | license | comment | |
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| May 11, 2018 at 5:27 | comment | added | Manh Nguyen | @joojaa I followed the math you guys give me and the animation is only correct for 1 out of the 2 models I am working on. Both are loaded by Assimp. The only differences I can think of are that 1 is a fbx file and the other is a dae file and that 1 has multiple mesh not situated at root scene and the other does. Is there something I am missing? The Assimp loader is able to load both models correctly. | |
| May 11, 2018 at 5:07 | comment | added | joojaa | @ManhNguyen that wouldnt work if you wanted to have multiple separate objects. But if you shift your reasoning one node up then it would work. Modeller has some leeway in deciding how the computation happens, but it seems that describing the world as a function of objects is a bit out there, but possible. | |
| May 11, 2018 at 4:54 | comment | added | joojaa | Usually the matrices are set up to describe object in parent space. But it is offcourse possible to store the inverses as the matrix like @ManhNguyen suggests. Ive never seen it done, somebody asked this i think and the answer was that for some reason it feels unnatural. Just as possible to set it up this way just like its possible to have a transposed matrix order in which case all calculations are reverse. So the dev needs to know this. | |
| May 11, 2018 at 4:46 | comment | added | Nathan Reed | @ManhNguyen Local transform takes you from the local space to the parent space, not the other way around. C space to world space would be ABC*v. | |
| May 11, 2018 at 4:40 | comment | added | Manh Nguyen | I thought the local transform of A should take you to B local space, then the local transform of B take you to C local space? for example, for a vertex in world space to get into C space, it needs to be multiplied by CBA*v. Then to get it from C space to world space you would get the inverse of it, which is (CBA)^-1 or A^-1*B^-1*C^-1? | |
| May 11, 2018 at 4:26 | history | answered | Nathan Reed | CC BY-SA 4.0 |