[Lite] Add public API for Lines

Questions
1

Hi,
I am currently trying to port a mid-size application to Babylon Lit (https://tuda-must.github.io/ITEP/library, ultrasound physics calculator). Here, I use LineMeshes for various things in the application. I could not find any equivalent to `CreateLineSystem` in Babylon Lite. Do you have any plans to add it or will it be a regular mesh with a different draw mode?

I recently learned that in BabylonJS, there is a difference in result between CreateLineSystem and load some lines from a GLTF. Maybe in the new Lite, it makes sense to thread both cases the same if possible.

Best regards,
Axel

2

I’ll be happy to work on that next! Stay tuned!

3

I’ve not used CreateLineSystem before, but I have a project that uses GreasedLine or DashedLines for roads (we tried it both ways and kept both branches of the code). @Deltakosh will the code your adding support either of those?

4

Nope this is not on the current plan for now:)

5

Pardon me horning-in on this thread for more line-related questions:

There’s current no direct lite support for wireframes, correct? From what I’ve seen, there are a view gizmo wireframes built “by hand” with createCylider, and there’s the PhysicsViewer wireframes that come directly from havok, and finally there’s a Material.wireframe boolean in babylon-lite-compat, but that doesn’t seem to be implemented anywhere.

Will the code for CreateLineSystem that you’re building now also end up powering wireframe support in the compat layer?

And finally, no pressure, but do you have a guess for when this will be available (days/weeks/months)?

Thanks so much!

6

Hey Brian!

Yes, that’s correct: generic mesh wireframe rendering isn’t supported in Lite yet. The compat API exposes Material.wireframe, but that flag isn’t connected to the renderer.

But I think I may have misunderstood the ask initially: the line APIs are already available on master: createLines, createLineSystem, and createDashedLines in “native Lite”, plus the corresponding MeshBuilder methods in compat. They currently render as 1px hardware lines.

That gives us a useful building block, but enabling wireframe on an existing mesh still needs a separate path to turn its triangle edges into lines and hook that up to the material flag. So the line-system work doesn’t automatically enable Material.wireframe.