Thanks for chiming in Germán. As @gbiggs said, we are not going to have an official simulator, but a set of recommended ones. It may happen that a given simulator is better suited for a specific scenario than others and it’ll be labeled as the default, very much like what ROS2 did with the DDS vendors. For example, ROS2 has no official DDS vendor, but there’s a default one that users can just assume will work well in most cases. Users are still free to use another DDS vendor if they want (e.g. they already have a license, their usecase is very specific, they want to run ROS2 on an unsupported OS/platform, etc.)
We just want to make it easier for our users to decide which simulator to use. In order to do that, we want to ensure that all the recommended simulators are well integrated with Autoware and with good performance, they all use open standards (e.g. Lanelet2, OpenDrive), have clear licensing that doesn’t restrict its use, etc.
On the more technical side, both @Dejan_Pangercic and @gbiggs have listed many of the features we’d like simulators to have. I’d say the highlights are being able to run faster than realtime, integration with CI (including scripting and headless) and a fairly realistic physics engine, but many others are also very important.
As I said, this is not a competition, so the more simulators that are well integrated with Autoware that our users can pick from, the better.
Having a clear, well-understood license that does not restrict the use is essential for all the simulators that we intend to collaborate with. I’m not a lawyer, but it seems that the Unreal license wouldn’t be a problem here, royalties are collected by Epic only if you sell the product that uses the Unreal engine, which doesn’t seem to be the case with Carla since it’s entirely opensource. Carla has a very common license for the code (MIT) and the assets (Creative Commons-BY). That doesn’t preclude anyone (including third parties) from taking Carla, repackaging it as a proprietary product and sell it, as long as they pay royalties to Epic, but that’s not a goal the Autoware Foundation has.