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Mesh formats in the Ignition App

Hey everyone,

I was noticing while using some of the resources available in the Ignition App (https://app.ignitionrobotics.org/dashboard) that a lot of the models in there use Collada (DAE) for its meshes. I am open to discuss this topic further, but I find DAE a very complicated format to use given that every software seems to have its own little changes to the format that make it unreadable on another (for example, I can’t open Collada files exported by 3ds Max into Blender).
Wouldn’t it be better to use Wavefront (OBJ), for instance, as preferred mesh format? It seems to be more consistent across 3D modeling softwares, at least.

Hello,

Gazebo doesn’t have a preferred mesh format. Currently, Gazebo supports STL, DAE, and OBJ mesh formats. When creating a model, you can use the mesh format of your choice. If you use a model created by another person, then you’ll have to use the provided mesh format or convert the mesh files.

I know Gazebo can import multiple formats.
I don’t mean really in Gazebo, I mean the models published in the Ignition App.
Some of the models if I try to convert them, I can’t really open them in some 3D modelling applications because the Collada format is weirdly different from what the importer can parse. OBJ just seems a bit more friendly across platforms.

The Ignition App follows the same philosophy as Gazebo, in that it doesn’t prefer one mesh format over another. It’s up to the creator of a model to choose a mesh format.

Just to complement @nate’s answer, here are some examples of models with other mesh formats in Fuel:

And a non-collada animation:

I understand. But some sources for 3D models for game development, for example, do provide at least multiple formats so that the user can pick the mesh format that fits best. It could be the case to encourage people to upload other formats as well, since it is such an import source of simulation assets.
I wrote this here mostly because most of the models I see there come from Open Robotics, so imagined you would have the originals in order to export to different (and more reliable) formats.
I say this out of experience trying to refactor Ignition App models by refactoring the DAE file manually and tweaking tags that are either not working with the simulation or in Blender.

In any case, this was just a suggestion. I will close this topic now and find another solution.

It would be helpful to know what models are not working properly.

Also note that the only format that both Gazebo and Ignition currently support for the skin of animated actors is DAE. (The animation itself can be DAE or BVH.)