When a mesh with scaling.x=-1 using PhysicsAggregate,its absoluteScaling will be auto changed to Vector(1,-1,1),why?

Bugs
1

Here is the playground,look at the cylinder,is that normal?

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This cylinder looks like it has automatically rotated 180 degrees on the x-axis.

@Cedric do you have any ideas?

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Orientation and scaling might be changed by the hierarchy matrix computation. It also happens with gizmos and in other places. Quick answer is to not use non uniform negative scaling.

At best orientation scaling is changed. At worst you have unconsistent rendering.

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So this is not a problem that needs to be fixed, right？But when I use gltf loader or importMesh, I see that it used negative scaling to convert leftHanded to rightHanded,it’ that a right way to do it ?

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I’ll check if I can find a fix for that.

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Thanks :grinning_face:

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There is no fix for this but a work around is possible with baked geometry. What is your use case?

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I imported a model from the glTF loader and I used the PhysicsAggregate to make it real,but when all settled,the model just rotate and falling through the ground due to the negative scaling.You mentioned that baked geometry,would you make a pg and I can learn the best way to optimize that?As you know,gltf loader would assign an empty mesh with negative scaling to convert the meshes to leftHanded if the scene is not useRightHanded,should I just baked the empty mesh?

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It will work if there is a parent transform of the _root_ transform from the gltf

I need to document that :slight_smile:

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For reference, here is the same PG when using right handed system on the scene (gltf becomes way simpler to handle):

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I forgot to mention the example I’ve posted works for LH and RH.