我正在尝试将Java脚本统一转换为csharp脚本，但出现一些错误？

Question

The script in csharp after converted:

using UnityEngine;
using System.Collections;

public class MYCLASSNAME : MonoBehaviour {


    public Transform TargetLookAt;

    public float Distance = 5.0f;
    public float DistanceMin = 3.0f;
    public float DistanceMax = 10.0f;

    private float mouseX = 0.0f;
    private float mouseY = 0.0f;
    private float startingDistance = 0.0f;    
    private float desiredDistance = 0.0f;

    public float X_MouseSensitivity = 5.0f;
    public float Y_MouseSensitivity = 5.0f;
    public float MouseWheelSensitivity = 5.0f;
    public float Y_MinLimit = -40.0f;
    public float Y_MaxLimit = 80.0f;

    public float DistanceSmooth = 0.05f;    
    private float velocityDistance = 0.0f;    
    private Vector3 desiredPosition = Vector3.zero;

    public float X_Smooth = 0.05f;
    public float Y_Smooth = 0.1f;
    private float velX = 0.0f;
    private float velY = 0.0f;
    private float velZ = 0.0f;
    private Vector3 position = Vector3.zero;

    CursorLockMode wantedMode;    


    void  Start (){
        Distance = Mathf.Clamp(Distance, DistanceMin, DistanceMax);
        startingDistance = Distance;
        Reset();
        SetCursorState();
        OnGUI();

    }

    void  LateUpdate (){
        if (TargetLookAt == null)
            return;

        HandlePlayerInput();

        CalculateDesiredPosition();

        UpdatePosition();
    }

    void  HandlePlayerInput (){
        float deadZone= 0.01f; // mousewheel deadZone

        //if (Input.GetMouseButton(1))
        //{
        mouseX += Input.GetAxis("Mouse X") * X_MouseSensitivity;
        mouseY -= Input.GetAxis("Mouse Y") * Y_MouseSensitivity;
        //}

        // this is where the mouseY is limited - Helper script
        mouseY = ClampAngle(mouseY, Y_MinLimit, Y_MaxLimit);

        // get Mouse Wheel Input
        if (Input.GetAxis("Mouse ScrollWheel") < -deadZone || Input.GetAxis("Mouse ScrollWheel") > deadZone)
        {
            desiredDistance = Mathf.Clamp(Distance - (Input.GetAxis("Mouse ScrollWheel") * MouseWheelSensitivity), 
                DistanceMin, DistanceMax);
        }
    }

    void  CalculateDesiredPosition (){
        // Evaluate distance
        Distance = Mathf.SmoothDamp(Distance, desiredDistance, velocityDistance, DistanceSmooth);

        // Calculate desired position -> Note : mouse inputs reversed to align to WorldSpace Axis
        desiredPosition = CalculatePosition(mouseY, mouseX, Distance);
    }

    float  CalculatePosition ( float rotationX ,   float rotationY ,   float distance  ){
        Vector3 direction = new Vector3(0, 0, -distance);
        Quaternion rotation = Quaternion.Euler(rotationX, rotationY, 0);
        return TargetLookAt.position + (rotation * direction);
    }

    void  UpdatePosition (){
        float posX= Mathf.SmoothDamp(position.x, desiredPosition.x, velX, X_Smooth);
        float posY= Mathf.SmoothDamp(position.y, desiredPosition.y, velY, Y_Smooth);
        float posZ= Mathf.SmoothDamp(position.z, desiredPosition.z, velZ, X_Smooth);
        position = new Vector3(posX, posY, posZ);

        transform.position = position;

        transform.LookAt(TargetLookAt);
    }

    void  Reset (){
        mouseX = 0;
        mouseY = 10;
        Distance = startingDistance;
        desiredDistance = Distance;
    }

    float ClampAngle ( float angle ,   float min ,   float max  ){
        while (angle < -360 || angle > 360)
        {
            if (angle < -360)
                angle += 360;
            if (angle > 360)
                angle -= 360;
        }

        return Mathf.Clamp(angle, min, max);
    }

    // Apply requested cursor state
    void SetCursorState ()
    {
        Cursor.lockState = wantedMode;
        // Hide cursor when locking
        Cursor.visible = (CursorLockMode.Locked != wantedMode);
    }

    void OnGUI ()
    {
        GUILayout.BeginVertical ();
        // Release cursor on escape keypress
        if (Input.GetKeyDown (KeyCode.Escape))
            Cursor.lockState = wantedMode = CursorLockMode.None;

        switch (Cursor.lockState)
        {
        case CursorLockMode.None:
            GUILayout.Label ("Cursor is normal");
            if (GUILayout.Button ("Lock cursor"))
                wantedMode = CursorLockMode.Locked;
            if (GUILayout.Button ("Confine cursor"))
                wantedMode = CursorLockMode.Confined;
            break;
        case CursorLockMode.Confined:
            GUILayout.Label ("Cursor is confined");
            if (GUILayout.Button ("Lock cursor"))
                wantedMode = CursorLockMode.Locked;
            if (GUILayout.Button ("Release cursor"))
                wantedMode = CursorLockMode.None;
            break;
        case CursorLockMode.Locked:
            GUILayout.Label ("Cursor is locked");
            if (GUILayout.Button ("Unlock cursor"))
                wantedMode = CursorLockMode.None;
            if (GUILayout.Button ("Confine cursor"))
                wantedMode = CursorLockMode.Confined;
            break;
        }

        GUILayout.EndVertical ();

        SetCursorState ();
    }
}

The errors on the lines:

Distance = Mathf.SmoothDamp(Distance, desiredDistance, velocityDistance, DistanceSmooth);

Error CS1502: The best overloaded method match for 'UnityEngine.Mathf.SmoothDamp(float, float, ref float, float)' has some invalid arguments (CS1502) (Assembly-CSharp)

Error CS1620: Argument 3 must be passed with the 'ref' keyword (CS1620) (Assembly-CSharp)

On the line:

desiredPosition = CalculatePosition(mouseY, mouseX, Distance);

Error CS0029: Cannot implicitly convert type 'float' to 'UnityEngine.Vector3' (CS0029) (Assembly-CSharp)

On the line:

return TargetLookAt.position + (rotation * direction);

Error CS0029: Cannot implicitly convert type 'UnityEngine.Vector3' to 'float' (CS0029) (Assembly-CSharp)

On the line:

float posX= Mathf.SmoothDamp(position.x, desiredPosition.x, velX, X_Smooth);

Error CS1502: The best overloaded method match for 'UnityEngine.Mathf.SmoothDamp(float, float, ref float, float)' has some invalid arguments (CS1502) (Assembly-CSharp)

Error CS1620: Argument 3 must be passed with the 'ref' keyword (CS1620) (Assembly-CSharp)

On the line:

float posY= Mathf.SmoothDamp(position.y, desiredPosition.y, velY, Y_Smooth);

Error CS1502: The best overloaded method match for 'UnityEngine.Mathf.SmoothDamp(float, float, ref float, float)' has some invalid arguments (CS1502) (Assembly-CSharp)

Error CS1620: Argument 3 must be passed with the 'ref' keyword (CS1620) (Assembly-CSharp)

On the line:

float posZ= Mathf.SmoothDamp(position.z, desiredPosition.z, velZ, X_Smooth);

Error CS1502: The best overloaded method match for 'UnityEngine.Mathf.SmoothDamp(float, float, ref float, float)' has some invalid arguments (CS1502) (Assembly-CSharp)

Error CS1620: Argument 3 must be passed with the 'ref' keyword (CS1620) (Assembly-CSharp)

Answer 1

The error literally states: 'argument must be passed with the ref keyword`. This means you have to add ref to the argument, to mark the parameter as in/out.

For example:

Distance = Mathf.SmoothDamp(Distance, desiredDistance, ref velocityDistance, DistanceSmooth);

For your function CalculatePosition , you simply defined the wrong return type. The code inside does not return a float, it returns a Vector3, as is natural for a position.

/* Does not return a float! */
Vector3 CalculatePosition(float rotationX, float rotationY, float distance)
{
    Vector3 direction = new Vector3(0, 0, -distance);
    Quaternion rotation = Quaternion.Euler(rotationX, rotationY, 0);
    return TargetLookAt.position + (rotation * direction);
}