Unity ecs physics collision

Unity DOTS中的物理系统即Unity.Physics，这里使用一个简单的demo（小球相撞效果），来说明一下 碰撞 Collision。
1、创建两个sphere（注意，要去掉ShpereCollider），添加Physics Shape，ShapeType 选择 Sphere，PhysicsShape 选择Collide Raise Collision Events。新建CollisionFilter类型Sphere和Plane，然后设置 BelongsTo = Sphere，设置CollidesWith = Sphere, Plane；添加 Physics Body。

2、创建三个plane（注意，要去掉MeshCollider），添加Physics Shape，ShapeType 选择 Plane，PhysicsShape 选择Collide。然后设置 CollisionFilter， BelongsTo = Plane，设置CollidesWith = Sphere；添加 Physics Body，MotionType设为Kinematic。

3、小球碰撞，触发逻辑

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using Unity.Entities;
using Unity.Mathematics;
using Unity.Transforms;
using Unity.Physics;
using Unity.Collections;
using Unity.Physics.Systems;public class PhysicalSystem : SystemBase
{
    private BuildPhysicsWorld buildPhysicsWorld;//物理系统的准备工作，将TriggerCollisionEvents传递给Jobprivate StepPhysicsWorld stepPhysicsWorld;//物理系统的准备工作，将TriggerCollisionEvents传递给Jobprotected override void OnCreate(){
    buildPhysicsWorld = World.GetOrCreateSystem<BuildPhysicsWorld>();stepPhysicsWorld = World.GetOrCreateSystem<StepPhysicsWorld>();}protected override void OnUpdate(){
    ColliderJob colliderJob = new ColliderJob(){
    velocitys = GetComponentDataFromEntity<PhysicsVelocity>()};Dependency = colliderJob.Schedule(stepPhysicsWorld.Simulation, ref buildPhysicsWorld.PhysicsWorld, Dependency);}
}public struct ColliderJob : ICollisionEventsJob
{
    public ComponentDataFromEntity<PhysicsVelocity> velocitys;public void Execute(CollisionEvent collisionEvent){
    if (velocitys.HasComponent(collisionEvent.EntityA) && IsSphere(collisionEvent.EntityA, "Sphere")){
    if (velocitys.HasComponent(collisionEvent.EntityB) && IsSphere(collisionEvent.EntityB, "Sphere")){
    var velocityA = velocitys[collisionEvent.EntityA];var dirA = -math.sign(velocityA.Linear.x);//Debug.Log("dirA = " + dirA);velocityA.Linear.x = dirA * 20;velocitys[collisionEvent.EntityA] = velocityA;var velocityB = velocitys[collisionEvent.EntityB];var dirB = -math.sign(velocityB.Linear.x);//Debug.Log("dirB = " + dirB);velocityB.Linear.x = dirB * 20;velocitys[collisionEvent.EntityB] = velocityB;}}}public bool IsSphere(Entity entity, string name){
    return World.DefaultGameObjectInjectionWorld.EntityManager.GetName(entity) == name;}
}