Create procedural use case demo

[TheDuckCow]

Thanks in part to the new "Roadside Assistance" Patreon tier, we have a formal request that we are committing to: a working example of the Road Generator in a procedural project.

Philosophy:

• Aim for simpler solutions over more complex yet comprehensive ones
• Readable and self-explanatory, so that the demo stands on its own and is easy for someone to follow
• Will be added to the demo folder of the main repo, which means a commitment of keeping it maintained and functional even as the Road Generator evolves

Current planned scope of this demo:

• [x] Provides a starting scene with any initial setup done in the editor
  • Enable the placement of RoadLanes for use by AI agents (this is just a tick box, but key point anyhow)
• [ ] Code which will randomly add connected roadpoints in both directions up to a certain distance, making sure they don't double back on each other while still being visually interesting
• [ ] Code which cleans up/removes old roadpoints further away than some distance
• [ ] Logic to randomly place entities aligned and facing the direction of the lanes of traffic
  • Likely dummy cars, which don't have any movement logic
  • For simplicity, will do just one entity per lane segment, so it'll look decently populated but then we're not worrying about overlapping placement (which would be more advanced and make the demo harder to follow)
• [ ] A basic controller for the "player" to move along the road
  • As of right now, will likely make this a "camera on rails" where you just press forward/backwards, sticking to the innermost left lane
  • This way, the demo doesn't have to spend time worrying about vehicle physics or handling tweaking
  • It also has the benefit that we could potentially use this demo scene for performance testing, by kicking up the camera speed to see how quickly we can generator road segments before frame rate drops (though this is a side benefit which may not come with the first version of the demo)

Out of scope (at least for the time being):

• Branching / intersections, to keep the scenario simpler
• Roadside placement of side structures (structures, vegetation, etc)
• Terrain - not a great use case for the time here, so we'll aim for a flat world
• Any treatment of different biomes

[brickyt]

Thanks @TheDuckCow for making this happen! Very excited and grateful for sharing your work with the community.

Understanding timelines can/will change, what's the ETA for the demo?

Cheers!

[TheDuckCow]

Sure thing @brickyt my plan is to get the majority of this done by the end of July. I'll link a branch here once I formally start working on it so you could always check out the progress. Worth me stating for anyone curious: The intention is to build this for Godot v3.5 but then whenever we port-forward the project to the godot4 branch (around the time of releases), it'll be available there too with hopefully most of the same functionality working. That godot4 port part though might not happen within July, we'll see.

[TheDuckCow]

A good chunk of initial work has already been done, see the demo video here and corresponding code of this draft PR:

https://github.com/TheDuckCow/godot-road-generator/assets/2958461/80b6e0d7-7224-4fd0-8f01-cdec950dd81f