Rotation point changes in SL when a mesh is mirrored

[Madeliefste Oh]

I observed something strange today. I have a mesh where the pivot point is not in the centre of the mesh. Also the menu shows a different size then the original mesh.

On picture 1 you see the original mesh highlighted, the mirrored one is next to it.

I mirrored the mesh in my 3d program, I use Cinema 4D. I mirrored the original with the symmetry tool. When you do so and make the symmetry object editable you get one object that consist of both meshes. What I did next is delete the original, en exported the mirrored one that was left.

After upload some things jumped in the eye.
- The rotation point is not in the centre, as you can see in picture 2, where the mirrored mesh is selected. 
- When you rez the mesh on the ground, it does not rezz on the floor but a metre or so above it. When I compare the height of both meshes in the menu, they have both the same size, but the the mirrored one looks smaller. It actually is smaller though the menu says both have the same size. Apparentely the menu adds some invisible space to the object when calculating the size. This is extreme on the X axis. The menu shows the mesh more then two times as big as it actually is, and that causes a shift of the rotation point.

For me this is complete unexpected behavoir, but still interesting behavior. Because normally when I want to give a mesh a different rotation point then the centre, I have to add an extra polygon to the mesh to force a different rotation point. 

When this can be reproduced, it might give us a nice work around for the pain with the pivot point.

Any people who work with other programs then C4D, who have seen this behavior before? Or can reproduce?

Has it anything to do that the mesh was mirrored, and that it sort of remembers it came from in object that had two halfs, with the pivot point right in between them? Or any other explanation for this?

 

 

 

 

 

[Chosen Few]

My guess is you've got some stray vertices left over from when you deleted the extra geometry.

[Madeliefste Oh]

I guess you are right.

I did not keep an original file of the mirrored mesh, only the .dae file. When I open that .dae I have a clean mesh, without any extra verticals. Now when I export that file again as a .dae and upload to SL, my mesh behaves like I would expect. Rotation point is in the centre.

But still I'm puzzeled, how can the .dae file that I upload to SL contain different information, then the same .dae file that I open in my program. The only thing I can think of is that it was late yesterday and I was tired, I might have saved over the 'corrupted' file after I upload it already... I don't remember exactly...