Negative scale does not play nicely with GE

[StjerneIdioten]

Objects that are mirrored by having a negative scale does not export properly to GE.

[StjerneIdioten]

Changed title since it turns out that mirroring wasn't the problem, but rather negative scale.

[StjerneIdioten]

Turns out the 'Problem' is a bit bigger than that. The exporter is doing its thing, but GE does not play nice with negative scale.

Negative scale is the only way to mirror a collection instance. But in GE the mesh object has to be a copy with vertices mirrored and normals flipped. Per axis that is mirrored.

[StjerneIdioten]

@NMC-TBone Any thoughts on this? It is only a problem for collection instances as for everything else we can just post a warning saying to not use negative scale for objects, but instances can only be mirrored like that as far as I am aware (unless something has changed)

[NMC-TBone]

@NMC-TBone Any thoughts on this? It is only a problem for collection instances as for everything else we can just post a warning saying to not use negative scale for objects, but instances can only be mirrored like that as far as I am aware (unless something has changed)

I actually had this open when you sent the comment 😂Negative scale is something I try to avoid at all costs. Yea exactly, thats the only way to mirror a instance.

I have never heard about anyone that really want this to work, so not sure if the time required to solve it is worth it in the end 😅

[StjerneIdioten]

I have never heard about anyone that really want this to work, so not sure if the time required to solve it is worth it in the end 😅

True, but as far as I understand spawning collection instances isn't necessarily out there when it comes to working in Blender now and I guess you probably want them mirrored sometimes. But it can definitely be achieved as well in other ways in Blender that don't lead to this annoying issue.