Amazing work

[jbousquie]

Hi,
Old core Babylon.js contributor here, just starting to play with three-d.
This message just to let know it's an amazing work so far :-)

Regards

Jerome

[asny]

Thank you so much 🙏 It's taken a lot of iterations to get to where it is today 🙂

[jbousquie]

sorry, I forgot : no, I wasn't paid. I have a (real) job besides in a french university institute.
Only the hired MS guys are paid afaik

[asny]

As a former OS project maintainer/contributor, I understand quite well what you mean ;-)

Always nice with someone who understands 😄

Oh, I didn't know it was hosted at Microsoft... or maybe I just forgot. I totally understand why it wasn't the same thing anymore. I guess "Things got too fast, too complex, less casual" could be said about a lot of software projects 😆 But nice to hear that it was a good experience.

three-d is definitely still slow and casual and I constantly try to keep the complexity down even though it's hard. So if you want to contribute, I'm very open to any kind of useful feature as long as it doesn't add too much complexity.

[jbousquie]

Thank you
But I'm still quite new to Rust and I just start to discover three-d, so it might take a while before I am able to contribute .

I'll try to play with instanced mesh next week as a start to learn the lib. I exactly like this simplicity and yet the power to render 3D stuff at 60 fps :-)

[asny]

No worries, no pressure at all 🙂

Sounds like a good plan. And that's great to hear, I tried to keep it simple and efficient. It's not optimal compared to a custom implementation but I think it's close in most cases.

[jbousquie]

First attempt with the instanced mesh done from the github example :
I just did a 10x10x10 cubes instanced mesh and applied a transformation (translation + rotation) to each instance every frame. This works fine at 60 fps in native (linux) or wasm mode.
Nevertheless, when creating a 20x20x20 cubes instanced mesh, the framerate drops down to 30 fps and down to 15 fps with a 30x30x30 cubes.
As I guess that the instanced mesh is drawn by a unique draw call, I really need to run a profiler to understand where's the bottleneck in my code (absolutly not optimized) knowing I was able to run transformations on several thousands of solids in BJS like in this old example : https://jerome.bousquie.fr/BJS/demos/facetdata5bis.html

Investigation started ;-)

[jbousquie]

ok got it
it's not the lib's fault, but mine (as usual)
cargo run --release, instead of cargo run, runs everything well at 60 fps ... even with a 40x40x40 cube

Really great lib :-)

[asny]

Great you figured it out 👌I've been there many times before, not understanding why it's suddenly slow, just to realise I forgot the release 🙂

[jbousquie]

It's the fate of unexperimented Rust devs like me :-D
I just did a stress test about the instanced mesh (with and without object memory allocation each frame : no perf difference at all)
https://github.com/jbousquie/threedtest/blob/master/src/main1.rs

The difference of performances between the debug and the release builds is huge.
And as expected, threed, being a Rust lib, is far more performant than babylonjs on such tests ... when building in release mode ;-)
I like it !

Going on playing with other features in order to discover the API and read some parts of the code...