Left and Right Handed shenanagins

BabylonJS is so cool I cannot sleep at night. But what is up with the coordinate system.

So I’m importing gltf models from Maya into Babylon scene. Setting up the camera I notice the coordinates seem to be backwards, but my models looks correct. Placing some GUI elements, same backwards coordinates. Hmmm…

So now I activate billboard mode on some of the imported mesh and they flip into this backwards coordinate system. ACK!

So I learn how to get the inspector in my scene and discover this weird “root” node with a negative Z scale. Ack again.

So now I learn about this lefthanded or righthanded system for gltf and my head is spinning.

Using the scene.useRightHandedSystem = true; switch makes my scene work EXCEPT I have to flip a few things that I added through code, which are now backwards. Not a big deal.

Did I do this the correct way, by using the scene.useRightHandedSystem = true ? The BILLBOARD seems to not work correctly in lefthanded mode, at least not with imported gltf models from Maya.

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It should work both ways as the intent of the root is actually to flip the model back.

You could set the useRightHandedSystem if you prefer to work as such but yes as long as there are no normalization of coordinates system it is a tough topic :slight_smile:

The mesh I’m affecting with the billboard is under the flipped root, causing it to flip in all 3 directions (I think all 3). I’ll setup a PG example when I can.