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dungeons/Assets/ThirdParty/UltimateXR/Runtime/Scripts/Manipulation/UxrGrabber.PhysicsSample.cs

112 lines
4.3 KiB
C#

// --------------------------------------------------------------------------------------------------------------------
// <copyright file="UxrGrabber.PhysicsSample.cs" company="VRMADA">
// Copyright (c) VRMADA, All rights reserved.
// </copyright>
// --------------------------------------------------------------------------------------------------------------------
using UnityEngine;
namespace UltimateXR.Manipulation
{
public partial class UxrGrabber
{
#region Private Types & Data
/// <summary>
/// Stores physics data of a frame to perform smooth throw computations.
/// </summary>
private class PhysicsSample
{
#region Public Types & Data
/// <summary>
/// Gets the sampled center of mass world position.
/// </summary>
public Vector3 CenterOfMass { get; }
/// <summary>
/// Gets the sampled finger tip world position.
/// </summary>
public Vector3 Tip { get; }
/// <summary>
/// Gets the sampled rotation.
/// </summary>
public Quaternion Rotation { get; }
/// <summary>
/// Gets the sampled angular speed in Euler angles.
/// </summary>
public Vector3 EulerSpeed { get; }
/// <summary>
/// Gets the sampled linear velocity in world space.
/// </summary>
public Vector3 Velocity { get; }
/// <summary>
/// Gets the sampled total velocity in world space. It is the result of combining the linear velocity plus the velocity
/// due to the throw axis angular speed. This should be used to compute throw release velocity.
/// </summary>
public Vector3 TotalVelocity { get; }
/// <summary>
/// Gets the elapsed time in seconds with respect to the previous sample.
/// </summary>
public float DeltaTime { get; }
/// <summary>
/// Gets or sets the sample age in seconds.
/// </summary>
public float Age { get; set; }
#endregion
#region Constructors & Finalizer
/// <summary>
/// Constructor.
/// </summary>
/// <param name="lastSample">Last frame data, to compute velocities</param>
/// <param name="sampledTransform">Transform, from the grabbed object if there is one currently being grabbed, otherwise from the grabber</param>
/// <param name="centerOfMass">World position of the throwing center of mass</param>
/// <param name="tip">World position of the finger tip approximation, to account for angular velocity in the throw</param>
/// <param name="deltaTime">Time in seconds since last frame</param>
public PhysicsSample(PhysicsSample lastSample, Transform sampledTransform, Vector3 centerOfMass, Vector3 tip, float deltaTime)
{
Age = 0.0f;
Rotation = sampledTransform.rotation;
DeltaTime = deltaTime;
CenterOfMass = centerOfMass;
Tip = tip;
if (lastSample != null)
{
// Angular
Vector3 v1 = lastSample.Tip - lastSample.CenterOfMass;
Vector3 v2 = tip - centerOfMass;
Vector3 rotationAxis = Vector3.Cross(v2, v1);
Quaternion relative = Quaternion.Inverse(lastSample.Rotation) * sampledTransform.rotation;
relative.ToAngleAxis(out float angle, out Vector3 axis);
EulerSpeed = (angle * sampledTransform.TransformDirection(axis)) / deltaTime;
// Linear. TODO: Improve using a mix of linear and angular components?
Velocity = ((tip - lastSample.Tip) / deltaTime);
TotalVelocity = Velocity;
}
else
{
EulerSpeed = Vector3.zero;
Velocity = Vector3.zero;
TotalVelocity = Velocity;
}
}
#endregion
}
#endregion
}
}