最近要写汽车的控制,发现比人物控制难很多,涉及到汽车的很多知识,自己写了一点不忍直视,各种bug,然后被告知untiy官方资源包里有控制脚本,就去学习了一下,然后借鉴了网上的一些教程,在这里表示衷心感谢,为了方面自己和他人,免得自己弄丢,然后贴在这里:
- using System;
- using UnityEngine;
- namespace UnityStandardAssets.Vehicles.Car//此处可改成自己的car名字
- {
- internal enum CarDriveType
- {
- FrontWheelDrive,//前驱
- RearWheelDrive,//后驱
- FourWheelDrive//四驱
- }
- internal enum SpeedType
- {
- MPH,//英里
- KPH//千米/h
- }
- public class CarController : MonoBehaviour
- {
- //[SerializeField]是为了成员变量可以在检视面板上显示
- [SerializeField] private CarDriveType m_CarDriveType = CarDriveType.FourWheelDrive; //四驱
- [SerializeField] private WheelCollider[] m_WheelColliders = new WheelCollider[4]; //存放轮子的数组
- [SerializeField] private GameObject[] m_WheelMeshes = new GameObject[4]; //车轮模型
- [SerializeField] private WheelEffects[] m_WheelEffects = new WheelEffects[4];//存放特效数组,粒子,音效等
- [SerializeField] private Vector3 m_CentreOfMassOffset;//车的重心
- [SerializeField] private float m_MaximumSteerAngle;//最大可转角度
- [Range(0, 1)] [SerializeField] private float m_SteerHelper; // 0 is raw physics , 1 the car will grip in the direction it is facing//初始化为0,1是车被控制面对的方向
- [Range(0, 1)] [SerializeField] private float m_TractionControl; // 0 is no traction control, 1 is full interference///0没有牵引力控制系统,1是完整的干扰
- //所有车轮的扭矩 扭矩越大,加速性能越好;扭矩越小,加速性能越差
- //如某车的1挡齿比(齿轮的齿数比,本质就是齿轮的半径比)是3,尾牙为4,轮胎半径为0.3米,原扭矩是200Nm的话,最后在轮轴的扭矩就变成200×3×4=2400Nm,
- //再除以轮胎半径0.3米后,轮胎与地面摩擦的部分就有2400Nm/0.3m=8000N,即800公斤力的驱动力,这就足以驱动汽车了
- //驱动力公式:驱动力=扭矩×变速箱齿比×主减速器速比×机械效率÷轮胎半径
- [SerializeField] private float m_FullTorqueOverAllWheels;//所有轮胎的扭矩
- [SerializeField] private float m_ReverseTorque;//反向扭矩
- [SerializeField] private float m_MaxHandbrakeTorque;//最大刹车扭矩
- [SerializeField] private float m_Downforce = 100f;//下压力
- [SerializeField] private SpeedType m_SpeedType;//速度类型
- [SerializeField] private float m_Topspeed = 200;//最大速度
- [SerializeField] private static int NoOfGears = 5;//档位数
- [SerializeField] private float m_RevRangeBoundary = 1f;//最大滑动距离
- [SerializeField] private float m_SlipLimit;//轮胎下滑给定的阈值
- [SerializeField] private float m_BrakeTorque;//刹车扭矩
- private Quaternion[] m_WheelMeshLocalRotations;//四元数组存储车轮本地转动数据
- private Vector3 m_Prevpos, m_Pos;
- private float m_SteerAngle; //转向角
- private int m_GearNum;//档位数
- private float m_GearFactor;//挡位因子
- private float m_OldRotation;//用于转动计算
- private float m_CurrentTorque;//当前扭矩
- private Rigidbody m_Rigidbody;//刚体
- private const float k_ReversingThreshold = 0.01f; //反转阈值
- //角色信息访问控制,对外接口
- public bool Skidding { get; private set; }
- public float BrakeInput { get; private set; }
- public float CurrentSteerAngle{ get { return m_SteerAngle; }}//当前车轮角度
- public float CurrentSpeed{ get { return m_Rigidbody.velocity.magnitude*2.23693629f; }}//当前速度
- public float MaxSpeed{get { return m_Topspeed; }}//最大速度
- public float Revs { get; private set; }//转速属性
- public float AccelInput { get; private set; } //加速输入
- // Use this for initialization
- //初始化
- private void Start()
- {
- m_WheelMeshLocalRotations = new Quaternion[4]; //获得车轮的四元数的角度信息
- for (int i = 0; i < 4; i++)
- {
- m_WheelMeshLocalRotations[i] = m_WheelMeshes[i].transform.localRotation;
- }
- m_WheelColliders[0].attachedRigidbody.centerOfMass = m_CentreOfMassOffset;
- m_MaxHandbrakeTorque = float.MaxValue;
- m_Rigidbody = GetComponent<Rigidbody>();
- //当前扭矩=全部扭矩-(牵引系数【0-1】*全部扭矩)
- //设置当前扭矩,初始化的扭矩值跟m_TractionControl大小有关,m_TractionControl决定是否有牵引力,如果m_TractionControl
- //值为0,则当前扭矩直接就是最大值,如果该值为1,则初始扭矩为0,然后汽车启动慢慢增加扭矩力。建议m_TractionControl数值为0.5
- m_CurrentTorque = m_FullTorqueOverAllWheels - (m_TractionControl*m_FullTorqueOverAllWheels);//
- }
- //变档函数
- private void GearChanging()
- {
- float f = Mathf.Abs(CurrentSpeed/MaxSpeed);
- float upgearlimit = (1/(float) NoOfGears)*(m_GearNum + 1);
- float downgearlimit = (1/(float) NoOfGears)*m_GearNum;
- if (m_GearNum > 0 && f < downgearlimit)
- {
- m_GearNum--;
- }
- if (f > upgearlimit && (m_GearNum < (NoOfGears - 1)))
- {
- m_GearNum++;
- }
- }
- //在0-1范围内为值添加一个曲线偏向1的简单函数
- // simple function to add a curved bias towards 1 for a value in the 0-1 range
- private static float CurveFactor(float factor)
- {
- return 1 - (1 - factor)*(1 - factor);
- }
- //松开插值的版本,允许值超出范围
- // unclamped version of Lerp, to allow value to exceed the from-to range
- private static float ULerp(float from, float to, float value)
- {
- return (1.0f - value)*from + value*to;
- }
- //计算齿轮因素/档位因子
- private void CalculateGearFactor()
- {
- float f = (1/(float) NoOfGears);
- // gear factor is a normalised representation of the current speed within the current gear's range of speeds.
- // We smooth towards the 'target' gear factor, so that revs don't instantly snap up or down when changing gear.
- //齿轮因素是在当前齿轮的速度范围的正常表示。我们顺利走向“目标”装备因素,所以转速时不要立即调节或向下改变齿轮。
- //目标齿轮数=(当前速度/最大速度)*最大齿轮数-当前齿轮数
- //我们要让值平滑地想着目标移动,以保证转速不会在变换档位时突然地上高或者降低
- //反向差值,通过当前速度的比例值,找当前速度在当前档位的比例位置,得到的值将是一个0~1范围内的值。
- var targetGearFactor = Mathf.InverseLerp(f*m_GearNum, f*(m_GearNum + 1), Mathf.Abs(CurrentSpeed/MaxSpeed));//反插值,计算比例值(5,10,8)=(8-5)/(10-5)=3/5
- m_GearFactor = Mathf.Lerp(m_GearFactor, targetGearFactor, Time.deltaTime*5f); //从当前档位因子向目标档位因子做平滑差值
- }
- //计算引擎转速(显示/声音)
- private void CalculateRevs()
- {
- // calculate engine revs (for display / sound)
- // (this is done in retrospect - revs are not used in force/power calculations)
- CalculateGearFactor();
- var gearNumFactor = m_GearNum/(float) NoOfGears;
- var revsRangeMin = ULerp(0f, m_RevRangeBoundary, CurveFactor(gearNumFactor));
- var revsRangeMax = ULerp(m_RevRangeBoundary, 1f, gearNumFactor);
- Revs = ULerp(revsRangeMin, revsRangeMax, m_GearFactor);
- }
- //运动函数,最重要
- public void Move(float steering, float accel, float footbrake, float handbrake)
- {
- //保持当前轮胎网格跟随wheelcolliders转动
- for (int i = 0; i < 4; i++)
- {
- Quaternion quat;//四元数quat,用于旋转
- Vector3 position;
- m_WheelColliders[i].GetWorldPose(out position, out quat);//获取wheelcolliders的姿势,位置和转向角
- //设置网格物体的位置和转向角
- m_WheelMeshes[i].transform.position = position;
- m_WheelMeshes[i].transform.rotation = quat;
- }
- //clamp input values
- steering = Mathf.Clamp(steering, -1, 1);//限制steering的值在-1和1之间,以下同上
- AccelInput = accel = Mathf.Clamp(accel, 0, 1);
- BrakeInput = footbrake = -1*Mathf.Clamp(footbrake, -1, 0);
- handbrake = Mathf.Clamp(handbrake, 0, 1);
- //Set the steer on the front wheels.
- //Assuming that wheels 0 and 1 are the front wheels.
- //设置前轮转向角,0,1为前轮,汽车行驶时也只是控制前轮转向
- m_SteerAngle = steering*m_MaximumSteerAngle;
- m_WheelColliders[0].steerAngle = m_SteerAngle;
- m_WheelColliders[1].steerAngle = m_SteerAngle;
- //调用角度辅助助手
- SteerHelper();
- //设置加速/刹车信息到WheelCollider
- ApplyDrive(accel, footbrake);
- //检查速度范围
- CapSpeed();
- //Set the handbrake.设置手刹
- //Assuming that wheels 2 and 3 are the rear wheels.2,3代表后轮
- if (handbrake > 0f)
- {
- //设置手刹值到后轮,达到减速目的
- var hbTorque = handbrake*m_MaxHandbrakeTorque;
- m_WheelColliders[2].brakeTorque = hbTorque;
- m_WheelColliders[3].brakeTorque = hbTorque;
- }
- //计算转速,用来供外部调用转速属性Revs来播放引擎声音等
- CalculateRevs();
- //改变档位
- GearChanging();
- //施加下压力
- AddDownForce();
- //检查轮胎
- CheckForWheelSpin();
- //牵引力控制系统
- TractionControl();
- }
- //检查速度范围
- private void CapSpeed()
- {
- float speed = m_Rigidbody.velocity.magnitude;//将标量速度赋予speed
- //判断速度类型,
- switch (m_SpeedType)
- {
- case SpeedType.MPH:
- speed *= 2.23693629f;
- if (speed > m_Topspeed)
- m_Rigidbody.velocity = (m_Topspeed/2.23693629f) * m_Rigidbody.velocity.normalized;//速度归一化
- break;
- case SpeedType.KPH:
- speed *= 3.6f;
- if (speed > m_Topspeed)
- m_Rigidbody.velocity = (m_Topspeed/3.6f) * m_Rigidbody.velocity.normalized;
- break;
- }
- }
- //设置加速/刹车信息到WheelCollider
- private void ApplyDrive(float accel, float footbrake)
- {
- float thrustTorque;
- switch (m_CarDriveType)
- {
- case CarDriveType.FourWheelDrive:
- thrustTorque = accel * (m_CurrentTorque / 4f);
- for (int i = 0; i < 4; i++)
- {
- m_WheelColliders[i].motorTorque = thrustTorque;
- }
- break;
- case CarDriveType.FrontWheelDrive:
- thrustTorque = accel * (m_CurrentTorque / 2f);
- m_WheelColliders[0].motorTorque = m_WheelColliders[1].motorTorque = thrustTorque;
- break;
- case CarDriveType.RearWheelDrive:
- thrustTorque = accel * (m_CurrentTorque / 2f);
- m_WheelColliders[2].motorTorque = m_WheelColliders[3].motorTorque = thrustTorque;
- break;
- }
- for (int i = 0; i < 4; i++)
- {
- if (CurrentSpeed > 5 && Vector3.Angle(transform.forward, m_Rigidbody.velocity) < 50f)
- {
- m_WheelColliders[i].brakeTorque = m_BrakeTorque*footbrake;
- }
- else if (footbrake > 0)
- {
- m_WheelColliders[i].brakeTorque = 0f;
- m_WheelColliders[i].motorTorque = -m_ReverseTorque*footbrake;
- }
- }
- }
- //此函数时move函数用于转向角
- private void SteerHelper()
- {
- for (int i = 0; i < 4; i++)
- {
- WheelHit wheelhit;
- m_WheelColliders[i].GetGroundHit(out wheelhit);
- if (wheelhit.normal == Vector3.zero)
- return; // wheels arent on the ground so dont realign the rigidbody velocity 车轮离地,则不用调整汽车角度了。
- }
- // this if is needed to avoid gimbal lock problems that will make the car suddenly shift direction
- //使用四元数避免万向锁的问题
- //假如上一次车体Y方向角度比这次小于十度,就根据相差的度数乘以系数m_SteerHelper,得出需要旋转的度数
- //根据这个度数算出四元数,然后将刚体速度直接旋转这个偏移度数
- if (Mathf.Abs(m_OldRotation - transform.eulerAngles.y) < 10f)
- {
- var turnadjust = (transform.eulerAngles.y - m_OldRotation) * m_SteerHelper;
- Quaternion velRotation = Quaternion.AngleAxis(turnadjust, Vector3.up);
- m_Rigidbody.velocity = velRotation * m_Rigidbody.velocity;
- }
- m_OldRotation = transform.eulerAngles.y;
- }
- // this is used to add more grip in relation to speed
- //这个是用来增加下压力,这是用来添加更多的速度控制
- private void AddDownForce()
- {
- m_WheelColliders[0].attachedRigidbody.AddForce(-transform.up*m_Downforce*
- m_WheelColliders[0].attachedRigidbody.velocity.magnitude);//Addforce 第一个车轮增加一个力,
- }
- // checks if the wheels are spinning and is so does three things 检查轮胎是否旋转
- // 1) emits particles 是否发射粒子
- // 2) plays tiure skidding sounds 播放滑行音
- // 3) leaves skidmarks on the ground 去掉刹车印
- // these effects are controlled through the WheelEffects class 这些特效都是通过类WheelEffects实现的
- private void CheckForWheelSpin()
- {
- // loop through all wheels 遍历所有车轮
- for (int i = 0; i < 4; i++)
- {
- WheelHit wheelHit;
- m_WheelColliders[i].GetGroundHit(out wheelHit);//获取碰撞信息
- // is the tire slipping above the given threshhold
- //轮胎下滑超过给定的阈值吗
- if (Mathf.Abs(wheelHit.forwardSlip) >= m_SlipLimit || Mathf.Abs(wheelHit.sidewaysSlip) >= m_SlipLimit)
- {
- //超出则发射烟雾粒子
- m_WheelEffects[i].EmitTyreSmoke();
- // avoiding all four tires screeching at the same time
- // if they do it can lead to some strange audio artefacts
- //避免四个轮胎都同时播放滑行声音
- //如果那样的话会导致某些奇怪的音效
- //函数AnySkidSoundPlaying()是遍历四个轮子,检查是否播放音效,是的返回ture.
- if (!AnySkidSoundPlaying())
- {
- m_WheelEffects[i].PlayAudio();
- }
- continue;
- }
- // if it wasnt slipping stop all the audio
- //假如没有超出阈值,还没有停止音效,则停止音效
- if (m_WheelEffects[i].PlayingAudio)
- {
- m_WheelEffects[i].StopAudio();
- }
- // end the trail generation
- //停止烟雾生成
- m_WheelEffects[i].EndSkidTrail();
- }
- }
- //如果汽车轮胎过度滑转,牵引力系统可以控制减少轮胎动力
- // crude traction control that reduces the power to wheel if the car is wheel spinning too much
- private void TractionControl()//牵引力控制函数
- {
- WheelHit wheelHit;
- //判断驱动类型,四轮,还是前后轮,然后调用AdjustTorque函数
- switch (m_CarDriveType)
- {
- case CarDriveType.FourWheelDrive:
- // loop through all wheels
- for (int i = 0; i < 4; i++)
- {
- m_WheelColliders[i].GetGroundHit(out wheelHit);
- AdjustTorque(wheelHit.forwardSlip);
- }
- break;
- case CarDriveType.RearWheelDrive:
- m_WheelColliders[2].GetGroundHit(out wheelHit);
- AdjustTorque(wheelHit.forwardSlip);
- m_WheelColliders[3].GetGroundHit(out wheelHit);
- AdjustTorque(wheelHit.forwardSlip);
- break;
- case CarDriveType.FrontWheelDrive:
- m_WheelColliders[0].GetGroundHit(out wheelHit);
- AdjustTorque(wheelHit.forwardSlip);
- m_WheelColliders[1].GetGroundHit(out wheelHit);
- AdjustTorque(wheelHit.forwardSlip);
- break;
- }
- }
- //当向前滑动距离超过阈值后,就说明轮胎过度滑转,则减少牵引力,以降低转速。上面函数调用
- private void AdjustTorque(float forwardSlip)
- {
- if (forwardSlip >= m_SlipLimit && m_CurrentTorque >= 0)
- {
- m_CurrentTorque -= 10 * m_TractionControl;
- }
- else
- {
- m_CurrentTorque += 10 * m_TractionControl;
- if (m_CurrentTorque > m_FullTorqueOverAllWheels)
- {
- m_CurrentTorque = m_FullTorqueOverAllWheels;
- }
- }
- }
- //函数AnySkidSoundPlaying()是遍历四个轮子,检查是否播放音效,是的返回ture.上面检查函数调用
- private bool AnySkidSoundPlaying()
- {
- for (int i = 0; i < 4; i++)
- {
- if (m_WheelEffects[i].PlayingAudio)
- {
- return true;
- }
- }
- return false;
- }
- }
- }