Using default CharacterController

Assets/Scenes/CharController.unity

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Assets/Scripts/InputReader.cs

 public class InputReader : MonoBehaviour, GameInput.IGameplayActions
 {
 	public UnityAction jumpEvent;
+	public UnityAction jumpCanceledEvent;
 	public UnityAction attackEvent;
 	public UnityAction interactEvent;
 	public UnityAction extraActionEvent;
 		if(jumpEvent != null
 			&& context.phase == InputActionPhase.Started)
 			jumpEvent.Invoke();
+
+		if(jumpCanceledEvent != null
+			&& context.phase == InputActionPhase.Canceled)
+			jumpCanceledEvent.Invoke();
 	}
 
 	public void OnMove(InputAction.CallbackContext context)

Assets/Scripts/Protagonist.cs

 public class Protagonist : MonoBehaviour
 {
 	public InputReader inputReader;
-	private Rigidbody rigidbody;
+	private CharacterController characterController;
-	public float airMomentumMultiplier = 3f;
-	public float jumpStrength = 1f;
-	private Vector3 momentum;
-	private bool isGrounded = true;
-	private bool jumpInitiated = false; //Becomes true on the frame that the jump button is pressed, consumed in FixedUpdate
+	public float gravityMultiplier = 10f;
+	public float jumpMultiplier = 5f;
+	public float initialJumpForce = 10f;
+	public float jumpInputDuration = 1f;
+
+	public float maxFallSpeed = 50f;
+
+	private float gravityCancel = 1f;
+	private bool isJumping = false;
+	private float jumpBeginTime = -Mathf.Infinity;
+	private float verticalMovement = 0f;
+	private Vector3 finalMovementVector;
+	private Vector3 movementVector;
-		inputReader.jumpEvent += OnJump;
+		inputReader.jumpEvent += OnJumpInitiated;
+		inputReader.jumpCanceledEvent += OnJumpCanceled;
 		inputReader.moveEvent += OnMove;
 		//...
 	}
 
 	private void Awake()
 	{
-		rigidbody = GetComponent<Rigidbody>();
+		characterController = GetComponent<CharacterController>();
-	private void FixedUpdate()
+	private void Update()
-		if (isGrounded)
+		finalMovementVector = movementVector * speed;
+		
+		gravityCancel += Time.deltaTime * 10f;
+
+		//Jump input timeout
+		if(isJumping)
-			if(jumpInitiated)
+			gravityCancel *= .5f;
+			//verticalMovement = verticalMovement + (gravityCancel * Time.deltaTime);
+
+			if(Time.time > jumpBeginTime + jumpInputDuration)
-				//Jump!
-				//rigidbody.AddForce(Vector3.up * jumpStrength, ForceMode.Impulse);
-				rigidbody.velocity = new Vector3(momentum.x * speed, jumpStrength, momentum.z * speed);
-				jumpInitiated = false;
-				isGrounded = false;
-			}
-			else
-			{
-				//Normal movement
-				rigidbody.MovePosition(rigidbody.position + momentum * Time.fixedDeltaTime * speed);
+				isJumping = false;
+				gravityCancel = 1f;
-		else
+
+		gravityCancel = Mathf.Clamp01(gravityCancel);
+		verticalMovement = verticalMovement + (Physics.gravity.y * gravityMultiplier * Time.deltaTime * gravityCancel); //Add gravity contribution
+
+		verticalMovement = Mathf.Clamp(verticalMovement, -maxFallSpeed, 100f);
+		finalMovementVector.y = verticalMovement;
+
+		characterController.Move(finalMovementVector * Time.deltaTime);
+
+		//Rotate to the movement direction
+		if(movementVector.sqrMagnitude >= .02f)
-			//In midair
-			rigidbody.AddForce(momentum * airMomentumMultiplier * Time.fixedDeltaTime * speed);
+			transform.forward = movementVector.normalized;
-		Debug.Log("Move " + movement);
-		momentum = new Vector3(movement.x, 0f, movement.y);
+		movementVector = new Vector3(movement.x, 0f, movement.y);
-	private void OnJump()
+	private void OnJumpInitiated()
-		if (isGrounded)
+		if(characterController.isGrounded)
-			jumpInitiated = true;
+			isJumping = true;
+			jumpBeginTime = Time.time;
+			verticalMovement = initialJumpForce;
+			gravityCancel = 0f;
-	private void OnCollisionEnter(Collision coll)
+	private void OnJumpCanceled()
-		isGrounded = true;
-		rigidbody.velocity = Vector3.zero;
+		isJumping = false;
 	}
 }