How to have same size of objects in different screen resolutions? - unity3d

Question

I'm working on a 2D game in Unity. I'm developing it for android and it's in portrait mode. I have placed one wall on left side of screen and one wall on right side of screen. The problem is the distance between those 2 walls is different in different screen resolutions. So, my character can't jump from one wall to other with the same velocity being applied.
I'm attaching an image to make my point clear.
What can I do so that in different devices, I get the same distance between these 2 walls? Any help will be appreciated.
EDIT: This is how I'm placing the walls right now.
screenLeft = Camera.main.ScreenToWorldPoint (new Vector3 (0f, 0f, 0f)).x;
screenRight = Camera.main.ScreenToWorldPoint (new Vector3 (Screen.width, 0f, 0f)).x;
rightWallSizeX = rightWall.GetComponent<SpriteRenderer> ().bounds.size.x;
leftWallSizeX = leftWall.GetComponent<SpriteRenderer> ().bounds.size.x;
rightWall.transform.position = new Vector3 (screenRight - rightWallSizeX/2, 0f, 0f);
leftWall.transform.position = new Vector3 (screenLeft + leftWallSizeX/2, 0f, 0f);

Answer 1

If you design your level using the editor:
Then the output aspect will be correct regardless its value:
As a bonus I've crafted you some code that lets the player stick to a wall and jump to the opposite side of it :D
using UnityEngine;
namespace Assets
{
public class PlayerController : MonoBehaviour
{
private const string Ground = "Ground";
private const string Wall = "Wall";
private Rigidbody2D _body;
private Vector2 _cNormal;
private GameObject _cWall;
private bool _joyAction;
private float _joyClimb;
private float _joyMove;
private State _state;
public float ForceClimb = 20.0f;
public float ForceJump = 5.0f;
public float ForceJumpFromWall = 10.0f;
public float ForceMove = 10.0f;
public float MaxMove = 15.0f;
private void Start()
{
_state = State.Air;
}
private void OnEnable()
{
_body = GetComponent<Rigidbody2D>();
}
private void Update()
{
_joyMove = Input.GetAxis("Horizontal");
_joyClimb = Input.GetAxis("Vertical");
_joyAction = Input.GetButtonDown("Fire1");
}
private void FixedUpdate()
{
var air = _state == State.Air;
var ground = _state == State.Ground;
var wall = _state == State.Wall;
if (air || ground)
{
var canJump = ground && _joyAction;
if (canJump)
{
var force = new Vector2(0.0f, ForceJump);
_body.AddForce(force, ForceMode2D.Impulse);
_state = State.Air;
}
var move = transform.InverseTransformDirection(_body.velocity).x;
if (move < MaxMove)
{
var force = new Vector2(_joyMove*ForceMove, 0.0f);
_body.AddRelativeForce(force);
}
}
else if (wall)
{
var climbing = Mathf.Abs(_joyClimb) > 0.0f;
if (climbing)
{
_body.AddForce(new Vector2(0, ForceClimb*_joyClimb));
}
else
{
var jumpingOut = _joyAction;
if (jumpingOut)
{
TryUnstickFromWall();
_body.AddForce(_cNormal*ForceJumpFromWall, ForceMode2D.Impulse);
}
}
}
}
private void OnGUI()
{
GUILayout.Label(_state.ToString());
}
public void OnCollisionEnter2D(Collision2D collision)
{
var c = collision.collider;
var t = c.tag;
if (t == Ground)
{
_state = State.Ground;
TryUnstickFromWall(); // fixes wall-sticking
}
else if (t == Wall && _state == State.Air) // jumping to wall
{
var wall = collision.gameObject;
var joint2D = wall.AddComponent<FixedJoint2D>();
var contact = collision.contacts[0];
var normal = contact.normal;
Debug.DrawRay(contact.point, normal, Color.white);
// stick 2 wall
joint2D.anchor = contact.point;
joint2D.frequency = 0.0f;
joint2D.autoConfigureConnectedAnchor = false;
joint2D.enableCollision = true;
_body.constraints = RigidbodyConstraints2D.FreezePositionX;
_body.gravityScale = 0.125f;
// save these
_cWall = wall;
_cNormal = normal;
// update state
_state = State.Wall;
}
}
public void OnCollisionExit2D(Collision2D collision)
{
if (collision.collider.tag == Ground)
{
_state = State.Air;
}
}
private void TryUnstickFromWall()
{
if (_cWall != null)
{
_body.constraints = RigidbodyConstraints2D.None;
_body.gravityScale = 1.0f;
var joint2D = _cWall.GetComponent<FixedJoint2D>();
if (joint2D != null) Destroy(joint2D);
_cWall = null;
}
}
}
internal enum State
{
Air,
Ground,
Wall
}
}
To try it:
create a layout like the one in picture 1
add a Rigidbody2D and BoxCollider2D to all of them
set their rigidbodies to be kinematic except for the player
add this script to the player
set walls tag to Wall
set ground tag to Ground
Then tweak it to your needs ...
EDIT:
You will have to encompass transform.InverseTransformDirection(_body.velocity).x with Mathf.Abs() to be correct, also at times the collision normal will be reversed making the player stuck to the wall, I let you figure this one :)