2D Physics Roadmap

Very interested! Basics like getting Super fast, primitive intersection tests with batching support not requiring 2D collider components are wonderful.

I was wondering if this in any way helps with local physics? moving platforms can be tricky / arcade games on vehicles and various moving objects etc with arcade rules mixing with physics are difficult but often needed.

I do love the entire roadmap though. I see a lot of stuff I'd love to mess with including LiquidFun!

 

That's wonderful for me. Eventually Unity has to stop adding things for people who can't code, especially if visual scripting can access these things you're exposing in future... else you'd be doing nothing but high level work for years to come

Any idea on times? In particular my sense of fun reaches out for LiquidFun for the lava in my 2D game... (and water). I guess we would want an array of these points or at least a starter mesh to do further rendering with, maybe it's rendered with the particle system?

 

Looks like a ton of work ahead of you, so thank you very much!

 

thankyou so much friend to make me already join this forum

 

Posting here as it might be relevant to future plans...

@MelvMay currently I find myself needing to see if a gameobject with one or more colliders (components on the same object OR as children) .... are overlapping another complex or simple arrangement.

I can get this with OnCollisionStay and filter out what I don't need but I'm not sure if this use case is possible now or in the future roadmap. I'll explain the situation:

I have a bunch of RPG style items such as swords, shields etc, and they all have different colliders, different numbers of colliders and so on, in short they're unique.

But most of the time they do not need to be simulated, only when they're dropped in the world. Bur when say, a sword is attacking, it needs to know if it's overlapped with a shield, and they both don't have any consistency with colliders.

So I'm not sure how to best check if the sword hit the shield, and if it didn't, check the sword hit the player and so on. I figure I can do it manually but that is a hell of a lot of colliders to check pairs for against....

TLDR: need to get a list of other colliders touching my complex gameobject mess of multiple colliders. This https://docs.unity3d.com/ScriptReference/Physics2D.OverlapCapsuleNonAlloc.html is fine, but my objects aren't just made of capsules, so I would have to peform multiple separate Overlap checks for boxes, capsules, circles, each time filtering out results that belong to the same gameobjects.

I feel that would be asking Physics2D to do a lot of redundant work.

 

That would work fine, how much quadtree work do I need to do to split space up to optimise it, or will it just discard things it won't potentially touch early on? and of course disabled colliders? I realised, I don't know a thing about the optimisations going on with Physics2D!

 

Sorry

 

Great to see this roadmap, very good improvements.

Currently for my project, i heavily used Physics2D.IgnoreCollision(Collider2D, Collider2D, bool), the case is:

There's a lot of star-ships, each ship composed by numbers of Rigidbody2D, the colliders in same ship will not collided with each other, but they will collide with other ship's. Because the ship count may larger than 32 so i can use layer based filter, there is only Physics2D.IgnoreCollision can works, but it is not elegant(since It is not persistent, more works need to do after collider enabled/disabled etc.).

So I wondering, if there's a collisionGroup or collisionLayer for colliders or rigidbody, each ship will has a certain group/mask id, the colliders will not collide with same id but will collide with all other which has different id. It will make things easier.

 

This sounds very cool. Glad to see it.

 

Can't wait to try the Low Level APIs, is there a estimated date?

 

Cool, If you push out dev videos/images, I would be very excited to read them, and try to take thinking about them especially the low-level primitive.

 

@MelvMay, there was an old issue I had in regards to PolygonCollider2D.SetPath being slower than I expected. I was wondering if any of these updates to 2D physics would improve the performance on this. Specifically the features of low-level collider primitives being exposed, multithreading, and asynchronous PolygonCollider2D triangulation.

This is the old issue I am referring to:

https://forum.unity.com/threads/polygoncollider2d-setpath-slow.349368/

 

Thanks. That sounds pretty amazing księgowa Jelenia Góra

 

@MelvMay Hi,
I see that - Expose low-level collider primitives of circle, edge, polygon & capsule and ability to retrieve from existing Collider 2D components is in development.
I created methods to visualize geometry queries (also I visualized quaternions and vectors).
https://github.com/uvivagabond/Visualization-of-physics-in-Unity
More info in wiki.
I must improve some of methods for better displaying, refactor some names and add support for future improvements for 2D physics.
In next few month I plan to describe all physics in unity and add additional methods to visualize.
Maybe this repository will be helpful for future improvements.

 

It's better to see the future improvements for 2D physics

 

Is there any possibility or planned feature to use 2D physics engine without components ? Like we did on standalone Box2D by pushing shape and rigidbody and listening collision events etc ?

Somehow like this

Code (CSharp):

1. Shape shape = new CircleShape(1f);
2. Body body = new Body(shape);
3. body.mass = 1;
4. body.onCollisionEnter += OnMyBodyCollide;
5. world.AddBody(body);

That would be very very good. Because i use MVC pattern in my projects and it is impossible to run physics without instantiating a game object. Which is useless in my case. So i usually use custom physics.

 

Hi, regarding Layers and Effectors :

Effector2D have a pretty unique trait : they let you override an object's collision mask on the fly, whithout having to create a whole new layer. (We have things like

Physics2D.IgnoreCollision

for object-to-object and

Physics2D.IgnoreLayerCollision

for layer-to-layer, but effectors are the only way to edit layer-to-object collisions.)
I've actually been using effectors in a project solely for this purpose, not for the fancy effects they provides.
Will we have something like an effectless effector for this purpose? Or a method to edit layer-to-object collision?
Any chance we get something similar in 3D ?

 

Thanks!

 

Very interesting!