A low-level rigidbody character movement solution that uses slope approximation to move smoothly across stairs and obstacles.

Smooth stair traversal without IK or mesh modification.

V2.0 WebGL Demo

Demo project

Key Features

:heavy_check_mark: Reliable slope traversal - Snap to angled ground surface while moving

:heavy_check_mark: Smooth stair traversal - Smoothly move up / down stairs and across obstacles

:heavy_check_mark: Supports moving surfaces - Correctly handle velocity on moving platforms

:heavy_check_mark: Intuitive collider adjustment - Configure collider height or step height while keeping collider bottom or top fixed

Environment

Developed and tested in Unity 6000.0.32f1

Quick Start

Installation

Install unitypackage from Releases

Usage Example

NoiRC.SRMove.AvatarMover is equivalent to Unity's CharacterContoller.

1. Add an AvatarMover component to your character gameobject.

2. In your own movement controller, implement your control logic.

   • Reference the AvatarMover component to handle actual movement.

using UnityEngine;
using NoiRC.SRMove;

// Example third-person movement controller.
public class MyMovementController : MonoBehaviour
{
    // Example input source that provides a Vector2 movement input every fame.
    [SerializeField] private MyInputSource _inputSource;

    [SerializeField] private AvatarMover _avatarMover;
    [SerializeField] private Transform _cam; // Reference transform used to determine movement direction.
    [SerializeField] private float _moveSpeed = 3f;

    private void FixedUpdate()
    {
        // Calculate the intended movement speed.
        float speed = _inputSource.HasInput() ? _moveSpeed : 0f;

        // Calculate the intended movement direction.
        Vector3 direction = GetMoveDirection(_input.GetMoveInput(), _cam);

        // Move.
        _avatarMover.Move(speed * direction);    
    }

    // Convert 2D input vector into 3D worldspace direction relative to the third-person camera.
    private Vector3 GetMoveDirection(Vector2 input, Transform cam)
    {
         Vector3 direction = (input.x * Vector3.ProjectOnPlane(cam.right, Vector3.up)).normalized;
         direction += (input.y * Vector3.ProjectOnPlane(cam.forward, Vector3.up)).normalized;
         return direction.normalized;
    }
}

Usage

Movement

Move(Vector3 velocity)

Set the intended movement velocity for one physics frame.

Jumping

AvatarMover expects you to drive jumps explicitly. The mover only manages grounding behaviour and velocity application — you decide the jump velocity profile and timing.

Use the provided methods to pause/resume grounding behaviour:

• LeaveGround()
• EndLeaveGround()

Example Jump Logic

Concept

A jump can be broken down into:

1. Start - character leaves ground - Jump starts here
2. Rising - character moves upward
3. Apex - character reaches highest point, rising stops - Jump stops here

"Jump duration" = time from the start (1) to the apex (3). You could use this duration with elapsed time to drive your jump velocity (e.g. a simple lerp or stylized curve).

Example

SimpleAvatarController

Keep calls to the mover exactly as shown below:

1. Whens starting a jump, call:

   LeaveGround()
   

   • Tells the mover you're intentionally leaving the ground.
   • The mover will stop trying to stick to ground / do slope detection while you're airborne.

2. During a jump, every fixed update, produce a jumpVelocity yourself and apply it using something like:

   Move(moveVelocity * airControlFactor + jumpVelocity)
   

   • Note: Do this in FixedUpdate so timing is stable.
   • moveVelocity - horizontal input / ground-relative velocity you want while in air.
   • airControlFactor - between 0 and 1, reduces horizontal control while airborne.
   • jumpVelocity - should be a Vector3 (typically only with a positive Y component).

3. When the jump is supposed to end (reached jump duration), call:

   EndLeaveGround()
   

   • Tells the mover you are no longer intentionally leaving ground.
   • After this call the mover will resume normal gravity/grounding behaviour (falling / landing detection).

Moving Surfaces

By default, a character using AvatarMover inherits the ground’s velocity (but not rotation) whenever it stands on a moving collider.

To make the character follow the moving collider's position and rotation, add a ParentableGround component to that moving collider gameobject.

• Ground Parenting: When the character stands on a gameobject with a ParentableGround component, it becomes a child of that gameobject and fully inherits its movement and rotation.

Status Properties

bool IsOnGround; // Whether the mover is currently on ground.
bool IsTouchingCeiling; // Whether the top of the mover's collider is touching a collider in the ground layer.
Collider GroundCollider; // The collider of the ground the mover is on.
bool IsParentedToGround; // Whether the mover is currently parented to the ground object.
Vector3 Up; // Up direction of the mover.