Tiny Physics Player Controller modification

Hello everyone,

I recently started working with ECS and Tiny. I love Project Tiny and I really appreciate it being open source! Thanks a lot!

Currently, I am trying to modify the Tiny Physics player controller. I want to get something like this third-person controller [1] but in a less advanced way. It is very important for me to do everything in pure ECS, to get some experience, and have good performing code.

The first milestone I want to reach is to make the camera follow the player and move around it by moving the mouse. Therefore I added the following components:

Code (CSharp):

1. using Unity.Entities;
2. using Unity.Tiny.Input;
3. using Unity.Tiny.Rendering;
4. using Unity.Mathematics;
5. using Unity.Transforms;
6.  
7. namespace TinyPhysics.Systems
8. {
9.     [UpdateBefore(typeof(CameraMovementSystem))]
10.     public class RotateWithMouseSystem: SystemBase
11.     {
12.         protected override void OnUpdate()
13.         {
14.              InputSystem input = World.GetExistingSystem<InputSystem>();
15.             ScreenToWorld s2w = World.GetExistingSystem<ScreenToWorld>();
16.             float2 inputPos = input.GetInputPosition();
17.             float3 cursorPos = s2w.InputPosToWorldSpacePos(inputPos, 4.0f);
18.  
19.             // calculate look direcction vector
20.             Entities.ForEach((ref CameraMoveable moveable, ref Translation position, ref LocalToWorld localToWorld) =>
21.             {
22.                 float3 lookDirection = cursorPos + position.Value;
23.                 quaternion lookRotation = quaternion.LookRotation(lookDirection, localToWorld.Up);
24.                 moveable.rotation = new quaternion(lookRotation.value.x, lookRotation.value.y, 0, lookRotation.value.w);
25.             }).ScheduleParallel();
26.         }
27.     }
28. }

Code (CSharp):

1. using Unity.Entities;
2. using Unity.Mathematics;
3.  
4. namespace TinyPhysics
5. {
6.     [GenerateAuthoringComponent]
7.     public struct CameraMoveable : IComponentData
8.     {
9.         public quaternion rotation;
10.         public float3 positionOffset;
11.         public float3 position;
12.         public Entity entityToFollow;
13.     }
14. }
15.  

Code (CSharp):

1. using Unity.Entities;
2. using Unity.Mathematics;
3. using Unity.Physics;
4. using Unity.Physics.Extensions;
5. using Unity.Transforms;
6.  
7. namespace TinyPhysics.Systems
8. {
9.     public class CameraMovementSystem : SystemBase
10.     {
11.         // EntityManager manager = World.DefaultGameObjectInjectionWorld.EntityManager;
12.         protected override void OnUpdate()
13.         {
14.             float deltaTime = Time.DeltaTime;
15.  
16.             Entities.ForEach((ref CameraMoveable moveable, ref Rotation rotation, ref Translation position, ref LocalToWorld localToWorld) =>
17.             {
18.                 // rotate camera
19.                 if (moveable.rotation.value.y != 0)
20.                 {
21.                     // rotation to world: localToWorld.Rotation
22.                     quaternion rotation_world = localToWorld.Rotation;
23.                     rotation.Value = moveable.rotation;
24.                 }
25.  
26.                 //// move camera
27.                 //if (true)
28.                 //{
29.                 //    Translation entPos = manager.GetComponentData<Translation>(moveable.entityToFollow);
30.                 //    position.Value = entPos.Value + moveable.positionOffset;
31.                 //}
32.  
33.             }).ScheduleParallel();
34.         }
35.     }
36. }
37.  

As you can see my code has not been finished, yet.

One of the problems I have is that I am not able to calculate a proper lookDirection for my camera. Answer #4 in this thread [2] stated how to calculate the position of the cursor in the world space. I thought subtracting it from the current position of the camera should give me a direction where the camera should look. But this doesn't work at all. I think I got something wrong here. May someone enlighten me on this matter?

Another problem I am having is that I cant make the camera follow the player entity. This video tutorial [3] illustrates how to set up a camera to follow an entity. The problem I am having here is that I can not access the position of the entity to follow. I wanted to use

GetComponentData<Translation>

to get the position but this only works with .WithoutBurst().Run() instead of ScheduleParallel() in the ForEach loop. Is there a way to get the current position of an entity in a more performant way? Or is there another solution to solve this problem?

As you can see I am new to ECS and I really appreciate any help! Thanks in advance!

Cheers
scuro

[1] https://assetstore.unity.com/packag...person-controller-basic-locomotion-free-82048
[2] https://forum.unity.com/threads/cant-get-camera-point-to-ray-in-tiny.917249/#post-6049001
[3] youtube.com/watch?v=JFv49-0vy_

 

Hey Abdul!
Thank you for your quick reply! Exactly what I was looking for. I will keep you updated on how it worked out.