* Moved ApplyBuoyancyForceSystem to UpdateAfter ExportPhysicsWorld to better match waves (minic older frame delay)

* added engine position back for drive
* tidied use of ComponentExtensions

Assets/Unity Physics Items/BuoyantObject_DOTS.cs

 
 		private void Start()
 		{
-			//Application.targetFrameRate = (int)(1f / Time.fixedDeltaTime);
+			Application.targetFrameRate = (int)(1f / Time.fixedDeltaTime);
 			_guid = gameObject.GetInstanceID();
 
 			Init();
 			{
 				float k = Mathf.Clamp01(waterLevel - (wp.y - voxelResolution)) / (voxelResolution * 2f);
 
-				submergedAmount += k / voxels.Length;//(math.clamp(waterLevel - (wp.y - voxelResolution), 0f, voxelResolution * 2f) / (voxelResolution * 2f)) / voxels.Count;
+				submergedAmount += k / voxels.Length;
 
 				var velocity = RB.GetPointVelocity(wp);
 				velocity.y *= 2f;
 		//Will be called by the PhysicsConversionSystem
 		public void Convert(Entity entity, EntityManager dstManager, GameObjectConversionSystem conversionSystem)
 		{
-			//Calculat all initial values
+			// Calculate all initial values
-			
-
-			
-			
-
-			//Add data needed for buoyancy
-			BuoyantData data = new BuoyantData();
+            //Add data needed for buoyancy
+            BuoyantData data = new BuoyantData();
 			data.type = _buoyancyType;
 			data.voxelResolution = voxelResolution;
 			data.localArchimedesForce = localArchimedesForce;
 			mass.CenterOfMass = centerOfMass;
 			dstManager.SetComponentData(entity, mass);
 
-
-			//Initialize the voxel and height buffers
-			DynamicBuffer<VoxelOffset> offsets = dstManager.GetBuffer<VoxelOffset>(entity);
+            //Initialize the voxel and height buffers
+            DynamicBuffer<VoxelOffset> offsets = dstManager.GetBuffer<VoxelOffset>(entity);
-			//Add engine position as first point
-			//offsets.Add(new VoxelOffset { Value = engine.enginePosition - centerOfMass });
-			//heights.Add(new VoxelHeight { Value = float3.zero });
+            //Add engine position as first point
+            var engine = GetComponent<Engine>();
+            if (engine)
+            {
+                offsets.Add(new VoxelOffset { Value = new float3(engine.enginePosition) - mass.CenterOfMass });
+                heights.Add(new VoxelHeight { Value = float3.zero });
+            }
-			//Add the rest of the positions
-			for (int i = 0; i < voxels.Length; i++)
+            //Add the rest of the positions
+            for (int i = 0; i < voxels.Length; i++)
-				offsets.Add(new VoxelOffset { Value = voxels[i] - centerOfMass });// transform.TransformPoint(voxels[i]) - transform.position }); // << Is this right?
+                offsets.Add(new VoxelOffset { Value = voxels[i] });
-			//Call other Convert methods
-			var body = GetComponentInChildren<BoatBodyComponent>();
-			//if (body)
-				body.Convert(conversionSystem.GetPrimaryEntity(body), dstManager, conversionSystem);
+            // Call other Convert methods
+            if (engine)
+                engine.Convert(conversionSystem.GetPrimaryEntity(engine), dstManager, conversionSystem);
+
+            var body = GetComponentInChildren<BoatBodyComponent>();
+            if (body)
+                body.Convert(conversionSystem.GetPrimaryEntity(body), dstManager, conversionSystem);
-			var engine = GetComponent<Engine>();
-			if (engine)
-				engine.Convert(conversionSystem.GetPrimaryEntity(engine), dstManager, conversionSystem);
-		}
+        }
-		struct DebugDrawing
+        struct DebugDrawing
 		{
 			public Vector3 force;
 			public Vector3 position;

Assets/Unity Physics Items/Systems/ApplyBuoyancyForceSystem.cs

 using Unity.Physics.Systems;
 using Unity.Physics;
 
-[UpdateAfter(typeof(GertsnerSystem)), UpdateBefore(typeof(BuildPhysicsWorld))]
+[UpdateAfter(typeof(GertsnerSystem)), UpdateAfter(typeof(ExportPhysicsWorld))]
 public class ApplyBuoyancyForceSystem : JobComponentSystem
 {
 
 	{
-		Debug.Log(string.Format("DeltaTime: {0}, Time.time {1}, Calc Delta: {2}", Time.deltaTime, Time.time, Time.time - lastTime));
-		lastTime = Time.time;
 		var job = new ForceJob()
 		{
 			dt = Time.fixedDeltaTime,
 			DynamicBuffer<VoxelOffset> offsets = offsetBuffer[entity];
 			DynamicBuffer<VoxelHeight> heights = heightBuffer[entity];
 
-			float submergedAmount = 0f;
-			//Debug.Log("new pass: " + entity.ToString());
-			float3 avPos = float3.zero;
-			float3 avForce = float3.zero;
-			float avgHeight = 0;
-			int total = 0;
-			//Apply buoyant force
-			for (var i = 0; i < offsets.Length; i++)
+
+            //Apply buoyant force
+            float submergedAmount = 0f;
+            for (var i = 0; i < offsets.Length; i++)
 			{
 				var wp = math.transform(entityTransform, offsets[i].Value);
 				float waterLevel = heights[i].Value.y;
-					//float depth = waterLevel - wp.y + (data.voxelResolution * 2f);
-					float subFactor = Mathf.Clamp01((waterLevel - (wp.y - data.voxelResolution)) / (data.voxelResolution * 2f));//depth / data.voxelResolution);
+					float subFactor = Mathf.Clamp01((waterLevel - (wp.y - data.voxelResolution)) / (data.voxelResolution * 2f));
-                    submergedAmount += subFactor / offsets.Length;//(math.clamp(waterLevel - (wp.y - voxelResolution), 0f, voxelResolution * 2f) / (voxelResolution * 2f)) / voxels.Count;
+                    submergedAmount += subFactor / offsets.Length;
-					//var force2 = data.localArchimedesForce * subFactor;
-					
-					
-					var velocity = ComponentExtensions.GetLinearVelocity(vel, mass, pos, rot, wp);
+					var velocity = vel.GetLinearVelocity(mass, pos, rot, wp);
-					var force = localDampingForce + math.sqrt(subFactor) * data.localArchimedesForce;//\
-					ComponentExtensions.ApplyImpulse(ref vel, mass, pos, rot, force * dt, wp);
-					//entity.ApplyImpulse(force, wp);//RB.AddForceAtPosition(force, wp);
-					avgHeight += force.y;
-					total++;
-					avPos += offsets[i].Value;
-					avForce += math.rotate(math.inverse(rot.Value), force * dt);
-					//Debug.Log(string.Format("ECS: Position: {0:f1} -- Force: {1:f2} -- Height: {2:f2}\nVelocty: {3:f2} -- Damp: {4:f2} -- Mass: {5:f1} -- K: {6:f2}", wp, force, waterLevel, velocity, localDampingForce, math.rcp(mass.InverseMass), dt));
+					var force = localDampingForce + math.sqrt(subFactor) * data.localArchimedesForce;
+					vel.ApplyImpulse(mass, pos, rot, force * dt, wp);
-				
-			//Update drag
-			//Debug.Log("Avg force: " + avForce / total + " Avg pos: " + avPos / total);
-			//Debug.Log($"Avg force: {avForce / total} Avg pos: {avPos / total}");
-			//submergedAmount /= offsets.Length;
-			//damping.Linear = Mathf.Lerp(data.baseDrag, 1f, submergedAmount);
-			//damping.Angular = Mathf.Lerp(data.baseAngularDrag, 1f, submergedAmount);
-
-			//data.percentSubmerged = Mathf.Lerp(data.percentSubmerged, submergedAmount, 0.25f);
-			//damping.Linear = data.baseDrag + (data.baseDrag * (data.percentSubmerged * 10f));
-			//damping.Angular = data.baseAngularDrag + (data.percentSubmerged * 0.5f);
-
 		}
 	}
 }

Assets/Unity Physics Items/Systems/DriveSystem.cs

 
 		public void Execute(Entity entity, int index, [ReadOnly] ref Translation pos, [ReadOnly] ref Rotation rot, ref PhysicsVelocity vel, [ReadOnly] ref PhysicsMass mass, ref DrivingData data)
 		{
-			
-			var wp = pos.Value + data.engineOffset;
-
-			//if (wp.y <= -0.1f) // if the engine is deeper than 0.1
-			//{
-				//accel
-				data.throttle = Mathf.Clamp(data.throttle, 0f, 1f); // clamp for reasonable values
-				float3 forward = math.forward(rot.Value);
-				forward.y = 0f;
-				forward = math.normalize(forward);
-				var force = (forward * data.throttle * data.horsePower) / mass.InverseMass; //divide by iMass to counteract mass in impulse method
-				var torque = (data.throttle * new float3(-1, 0, 0)) / mass.InverseInertia;
+            var entityTransform = new RigidTransform(rot.Value, pos.Value);
+			var wp = math.transform(entityTransform, data.engineOffset+mass.CenterOfMass);
+            if (wp.y <= -0.1f) // if the engine is deeper than 0.1 
+			{
+                data.throttle = Mathf.Clamp(data.throttle, 0f, 1f); // clamp for reasonable values
+                float3 forward = math.forward(rot.Value);
+                forward.y = 0f;
+                forward = math.normalize(forward);
-
+                //accel
+                var force = (forward * data.throttle * data.horsePower) / mass.InverseMass; //divide by iMass to counteract mass in impulse method
-				ComponentExtensions.ApplyLinearImpulse(ref vel, mass, force * dt);
-				//ComponentExtensions.ApplyLinearImpulse(ref vel, mass, up * 20000f * dt);
-			//ComponentExtensions.ApplyAngularImpulse(ref vel, mass, torque * dt);
-			//RB.AddForce(forward * modifier * horsePower, ForceMode.Acceleration); // add force forward based on input and horsepower
-			//RB.AddRelativeTorque(-Vector3.right * modifier, ForceMode.Acceleration);
+				vel.ApplyLinearImpulse(mass, force * dt);
-
-
-			//Turning
-			data.steering = Mathf.Clamp(data.steering, -1f, 1f); // clamp for reasonable values
-				var sTorque = new float3(0f, data.torque, -data.torque * .5f) * data.steering / mass.InverseInertia;
-				ComponentExtensions.ApplyAngularImpulse(ref vel, mass, sTorque * dt);
-				//Debug.Log(string.Format("Force: {0}, Torque: {1} Throttle: {2}", force, sTorque, throttle));
-				//RB.AddRelativeTorque(new Vector3(0f, torque, -torque * 0.5f) * modifier, ForceMode.Acceleration); // add torque based on input and torque amount
-			//}
+                //Turning
+                var torque = (data.throttle * new float3(-1, 0, 0)) / mass.InverseInertia;
+                data.steering = Mathf.Clamp(data.steering, -1f, 1f); // clamp for reasonable values
+			    var sTorque = new float3(0f, data.torque, -data.torque * .5f) * data.steering / mass.InverseInertia;
+				vel.ApplyAngularImpulse(mass, sTorque * dt);
+			}
 		}
 	}
 }