Recast/Detour/Detour crowd based navigation

slapin

As I need proper navigation and the one in Godot is very basic one, I decided to implement full-blown navigation based on Detour/Detour Crowd. This appears to have very low people interest, but still there are some people who need this. I publish my progress here https://uncertain-games.blogspot.com/ but there might be some unrelated gibberish or NSFW stuff, so be warned. Latest progress entity is there: https://uncertain-games.blogspot.com/2018/08/finally-i-fixed-all-navmesh-generation.html Navigation takes very little time to process and works very well, but I did not implement a set of editor nodes and everything currently is scripted. Navigation mesh is generated at runtime using group of objects. Agents are controlled by navigation. As soon as all features are controllable in script I will add editor nodes for crowd and agents for easy manipulation and will allow navmesh baking in editor so it can be loaded as file and not generated every time. The TODO is big but it is already much more usable for me than stock navigation as it - builds navmesh at run time and allows rebuilding tile-by-tile (fast) - allows a lot of agents running with collision avoidance without need of physics, however allowing limits and flexibility, so it works with custom motion and root motion, and physics-based motion is supported as well.

slapin

Megalomaniak

Yes, this is very interesting indeed. Definitely going to keep following this.

TwistedTwigleg

As I need proper navigation and the one in Godot is very basic one, I decided to implement full-blown navigation based on Detour/Detour Crowd. This appears to have very low people interest, but still there are some people who need this.

Having used Godot's default navigation a couple times, having something else like Detour in Godot would be amazing! One question though (just out of curiosity), is this using GDNative (C++), or another programming language like GDScript or C#?

slapin

it is C++ module

TwistedTwigleg

@slapin said: it is C++ module

Neat! I will definitely have to keep my eye on this :smile:

MagicLord

@slapin said: As I need proper navigation and the one in Godot is very basic one, I decided to implement full-blown navigation based on Detour/Detour Crowd. This appears to have very low people interest, but still there are some people who need this.

Because most Godot users are not working on 3D games , and because few Godot 3D games showcased are not about AI characters able to move anywhere.

@slapin said: - builds navmesh at run time and allows rebuilding tile-by-tile (fast) - allows a lot of agents running with collision avoidance without need of physics, however allowing limits and flexibility, so it works with custom motion and root motion, and physics-based motion is supported as well.

Do you plan an option to bake the navmesh instead of using run time generation ?

Can agents work with physics ? For example each agent should keep it's capsule collision kinematicBody following the navigation system. Because characters must be able to detect collisions or raycast against other for gameplay.

Navmesh seems to have lot of vertex, with less vertex would it work faster and better ?

Perhaps your navigation system will become the main one Godot will use after Godot 3.1 is released :)

slapin

Yes, baking will be implemented.

Yes, you can use physics based motion. You can control your agents yourself. Your agent position should not be too different from one provided by navigation though (obviously) or navigation errors will be produced resulting in jerky motion. But common physics based motion using forces/impulses and root motion and vehicle motion work fine. The only direct control method provided is direct setting of coordinates, otherwise you just recieve signal for positioning and handle it yourself.

Mesh density is a balance between quality of motion, and speed. The big squares you see are tiles, so actual navmesh density on the example is low. Tiles can be added/removed/rebuilt on demand.

As I finish adding basic recastnavigation features like tile cache, navigation areas and offmesh connections I will create video demonstrating the features.

Currently it all is used via script, no editor helper nodes are implemented, as I will complete all basic features, I will add editor helper nodes for crowd and implement navmesh baking.

MagicLord

@slapin said: Yes, you can use physics based motion. You can control your agents yourself. Your agent position should not be too different from one provided by navigation though (obviously) or navigation errors will be produced resulting in jerky motion. But common physics based motion using forces/impulses and root motion and vehicle motion work fine. The only direct control method provided is direct setting of coordinates, otherwise you just recieve signal for positioning and handle it yourself.

I would like to see how it works. With Unity and object can have physics and can contain also an agent for navigation. You can move the object using the agent or the physics, when you use the agent and navigation to move it overrides the physics rigidBody or Kinematic , physics are still there but they follow the agent position.

slapin

Currently I support any Spatial derived object. it is either controlled directly or via signals.You have to do all controlling logic yourself if you use physics or other behavioral motion for now.

MagicLord

@slapin said: Currently I support any Spatial derived object. it is either controlled directly or via signals.You have to do all controlling logic yourself if you use physics or other behavioral motion for now.

With Unity agent, you use "movetoDestionation()" and this uses the agent properties (speed, turning speed, acceleration, deceleration stopping distance) to move to a point, this is not physics, but the object keeps it's physics properties if it has some like collision volumes and collisions detection. When you don't use the agent functions, you can move manually the object ( kinematic changing it's position, with forces functions for RigidBody object). Any time you can stop some motion and switch between Agent or object manual movement.

slapin

If you want something like that please add issues to the repo, or better send PRs. I currently work on core functionality, so I will come to this later (3 weeks or so). Currently crowd support a set of 16 sets of agent parameters and 16 set of navmesh filtering parameters. These can be chosen on addition to the crowd. So you can do all that but with a bit of manual labour.

slapin

CSG meshes are supported now by navigation_pr or my navigation branch. Feel free to test and send feedback.