Computing Matrix Transformation for Static Mesh Import

[Anonymous]

Hello

I am having quite a hard time getting my head around the transformation Matrices I have to apply to the verteces of a model to bring it back to its pivot for submeshes that defines collision boxes

for eg :

Mesh A has a pivot in max

   SubMesh1 is a partial collision mesh 

   SubMesh2 is a partial collision mesh 

When importing the MeshA I am using this matrix to apply on control point and it works fine ( I get the Pivot where  I want and all is epxressed against it ). This matrix is defined as such

Translation = Node->GetGeometricTranslation(FbxNode::eSOURCE_SET);
Rotation = Node->GetGeometricRotation(FbxNode::eSOURCE_SET);
Scaling = Node->GetGeometricScaling(FbxNode::eSOURCE_SET);
Geometry.SetT(Translation);
Geometry.SetR(Rotation);
Geometry.SetS(Scaling);

then on submodel this becomes tricky as I am applying same SubNode's Matrix and multiply it with parents matrix as computed above.

=> Sometimes it work like a charm and I get nice collision boxes around my model while sometimes, on other models Collision boxes are all messed up. 

When this happens, I got some movement in the ( Local Translation for eg ) that I migth have forgotten to include ? 

Anyway, Overall the idea is to compute a matrix transformation that I could apply in submesh to put them in the pivot frame of its master. What should I do ? 

thanks

[Anonymous · Accepted solution]

Never better served than by myself 🙂

So

1) the Parent mesh gets its pivot orientation ( geo )  applied to its raw verteces

2) Child gets only their Local * Geo transformation

and there we go all expressed to the origin but shifted to the pivot frame !