Potential Issue with BILLBOARDMODE_Y in Right-Handed System

Bugs
1

Hello,

I’ve recently encountered a potential issue with billboard mode when using the right-handed system.

Specifically, BILLBOARDMODE_Y doesn’t appear to function as expected - it doesn’t make the mesh face the camera by default, unlike BILLBOARDMODE_ALL. This behavior seems inconsistent and potentially incorrect.

Here’s what I observed:

In the left-handed system:

  • BILLBOARDMODE_ALL → Mesh correctly faces the camera
  • BILLBOARDMODE_Y → Mesh correctly faces the camera

In the right-handed system:

  • BILLBOARDMODE_ALL → Mesh correctly faces the camera
  • BILLBOARDMODE_Y → Mesh does not face the camera (this seems incorrect)

Is this the intended behavior, or could it be a bug? I’d appreciate any clarification or insight.

Here is the playground to reproduce (click on the button to toggle billboard mode): https://playground.babylonjs.com/#ZI9AK7#4396

Thanks!

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2

cc @bghgary

4

Seems like a bug. I’ll investigate as soon as possible.

cc @Deltakosh for when he is back

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5

There are some issues for sure, but even the basics seem wrong. For example, Babylon.js Playground looks fine in LH, but RH the UVs are flipped.

If this isn’t blocking, let’s wait until @Deltakosh is back next week.

1 Like
8

UV in RH are not changed. This is not a bug but more a design decision :slight_smile:
Looking at @Roman_Diadiushkin problem right now

9

Here we are:
Fix Billboard individual mode in RH by deltakosh · Pull Request #16878 · BabylonJS/Babylon.js

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