How to optimize movement script using CharacterController component?

Question

I've made a very basic character controller using a CharacterController component. I'm still a beginner so I keep learning new things. My problem is how to optimize my controller script. Also, I would like to learn more about physics and things like this but I can't find any good tutorial or documentation, so if you know where I can find some interesting information (I'm not talking about Google here), I'd be glad if you share them with me.

My character falls way too slowly. Also, I can midair movement should be limited. My next problem is that my character levitates after hitting a platform or something with its head before reaching its max jump height. Another thing is that it can "levitate" next to platform just because it touches a collider, where normally it should just fall down.

So here's the code:

using UnityEngine;
using System.Collections;

public class PlayerController : MonoBehaviour {

public float moveSpeed = 9.5f;
public float jumpSpeed = 1.5f;
public float gravity = 7.0f;

CharacterController controller;
Vector3 currentMovement;

public Transform [] startPoint;

void Start () 
{
    controller = GetComponent<CharacterController>();
}


void Update () 
{
    currentMovement = new Vector3(Input.GetAxis("Horizontal") * moveSpeed, currentMovement.y, Input.GetAxis("Vertical") * moveSpeed);

    if(!controller.isGrounded) // Można również zapisać jako if(controller.isGrounded == false)
        currentMovement -= new Vector3(0, gravity * Time.deltaTime, 0); // Można zapisać jako currentMovement.y -= new Vector3(0, -gravity * Time.deltaTime, 0)
    else
        currentMovement.y = 0;

    if(controller.isGrounded && Input.GetKey(KeyCode.Space))
    {
        currentMovement.y = jumpSpeed;
    }

    controller.Move(currentMovement * Time.deltaTime);

    if(Input.GetKeyDown(KeyCode.X))
    {
        gameObject.transform.position = startPoint[0].position;
    }

    if(Input.GetKeyDown(KeyCode.Escape))
    {
        Application.LoadLevel(0);
    }
}
}

Answer 1

Your character falls too slowly because of these two lines:

currentMovement -= new Vector3(0, gravity * Time.deltaTime, 0); //multiply by deltaTime
controller.Move(currentMovement * Time.deltaTime); //multiply by delta time again