Advanced Tips for Player Movement in Unity

Creating fluid and responsive player movement is crucial for delivering an engaging gameplay experience, especially in third-person games. This article provides advanced tips for optimizing and enhancing player movement in Unity, including handling complex terrain, implementing inertia, and sophisticated camera control for third-person perspectives.

Handling Complex Terrain

Navigating complex terrain, such as uneven surfaces or slopes, requires careful handling to maintain smooth movement and prevent unrealistic behavior like slipping or sliding.

Using Raycasts for Slope Detection

Implement raycasting to detect the angle of the terrain under the player. This allows you to adjust the player's movement speed and control when navigating slopes.

using UnityEngine;

public class AdvancedMovement : MonoBehaviour
{
    public float walkSpeed = 5f;
    public float slopeLimit = 45f;
    public LayerMask groundLayer;
    public Transform cameraTransform;
    public float cameraDistance = 5f;
    public float cameraSensitivity = 2f;

    private Rigidbody rb;
    private bool isGrounded;

    void Start()
    {
        rb = GetComponent();
    }

    void Update()
    {
        HandleMovement();
        HandleCamera();
        CheckGround();
    }

    void HandleMovement()
    {
        float moveHorizontal = Input.GetAxis("Horizontal");
        float moveVertical = Input.GetAxis("Vertical");

        Vector3 move = transform.right * moveHorizontal + transform.forward * moveVertical;

        if (isGrounded)
        {
            move = AdjustForSlope(move);
        }

        rb.velocity = new Vector3(move.x, rb.velocity.y, move.z);
    }

    Vector3 AdjustForSlope(Vector3 move)
    {
        RaycastHit hit;

        if (Physics.Raycast(transform.position, Vector3.down, out hit, 1.5f, groundLayer))
        {
            float slopeAngle = Vector3.Angle(hit.normal, Vector3.up);

            if (slopeAngle <= slopeLimit)
            {
                return Vector3.ProjectOnPlane(move, hit.normal);
            }
        }

        return move;
    }

    void CheckGround()
    {
        isGrounded = Physics.Raycast(transform.position, Vector3.down, 1.1f, groundLayer);
    }

    void HandleCamera()
    {
        float mouseX = Input.GetAxis("Mouse X") * cameraSensitivity;
        float mouseY = Input.GetAxis("Mouse Y") * cameraSensitivity;

        Vector3 rotation = cameraTransform.localEulerAngles;
        rotation.y += mouseX;
        rotation.x -= mouseY;
        rotation.x = Mathf.Clamp(rotation.x, -80, 80);

        cameraTransform.localEulerAngles = rotation;
        cameraTransform.position = transform.position - cameraTransform.forward * cameraDistance;
    }
}

Implementing Inertia and Momentum

Adding inertia and momentum can make movement feel more natural and responsive, especially in fast-paced games or those with realistic physics.

Smoothing Movement Transitions

Use physics properties like drag and angular drag to smooth out movement transitions. This prevents sudden stops and starts, providing a more realistic experience.

void HandleMovement()
{
    float moveHorizontal = Input.GetAxis("Horizontal");
    float moveVertical = Input.GetAxis("Vertical");

    Vector3 move = transform.right * moveHorizontal + transform.forward * moveVertical;
    move *= walkSpeed;

    if (move != Vector3.zero)
    {
        rb.drag = 1; // Smooths out sudden stops
    }
    else
    {
        rb.drag = 5; // Increases drag when not moving
    }

    rb.AddForce(move, ForceMode.Acceleration);
}

Customizing Movement for Different Game Genres

Different game genres require unique movement characteristics. For instance, platformers often feature precise jumping and air control, while racing games emphasize inertia and speed control.

Platformers: Precision and Control

In platformers, control over jumping and landing is critical. Implement coyote time (a brief window allowing the player to jump after leaving a platform) to provide forgiving and precise jumping mechanics.

private float jumpCooldown = 0.1f;
private float lastGroundedTime;
private bool canJump => Time.time - lastGroundedTime <= jumpCooldown;

void Update()
{
    if (isGrounded)
    {
        lastGroundedTime = Time.time;
    }

    if (Input.GetButtonDown("Jump") && canJump)
    {
        rb.velocity = new Vector3(rb.velocity.x, jumpForce, rb.velocity.z);
    }
}

Racing Games: Inertia and Drift

For racing games, managing inertia and drift is essential. Implementing physics-based turning and drift mechanics can enhance the sense of speed and control.

public float turnSpeed = 5f;
public float driftFactor = 0.95f;

void Update()
{
    float turn = Input.GetAxis("Horizontal");

    // Apply turning
    transform.Rotate(0, turn * turnSpeed * Time.deltaTime, 0);

    // Apply drift
    rb.velocity = transform.forward * rb.velocity.magnitude * driftFactor;
}

Conclusion

Advanced player movement involves not just basic input handling, but also refining the feel of movement through physics and control mechanics. By addressing complex terrain, incorporating inertia, and tailoring movement systems to your game's genre, you can significantly enhance player experience. In third-person games, camera control is crucial; ensure smooth and responsive camera movement to complement player control.

Remember, the key to great movement systems is iteration and feedback. Test your controls extensively and refine them based on player input to ensure the best possible gameplay experience.