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@Kudoshi
Forked from ditzel/ScrollAndPinch.cs
Last active October 25, 2023 08:29
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Pinch and Scroll to Move and Zoom in Unity for Mobile Games
/*
Original Script By: Ditzel
Youtube Video Link: https://www.youtube.com/watch?v=KkYco_7-ULA&ab_channel=DitzelGames
Uses of this script:
For controlling camera movement: Pan, zoom and rotate
How to use:
Set this on an empty game object positioned at (0,0,0) and attach your active camera.
The script only runs on mobile devices or the remote app.
DecreaseCameraPanSpeed - The more the value, the greater it slows the pan speed
Upper height (Zoom out restriction) - Relative to camera position (not worldspace)
Lower height (Zoom in restriction) - Relative to camera position (not worldspace)
------[CHANGE LOG]------
Edited by Kudoshi : 24/3/2021
- Added Zoom In Out restriction
- Added camera pan speed
*/
using UnityEngine;
class ScrollAndPinch : MonoBehaviour
{
#if UNITY_IOS || UNITY_ANDROID
public Camera Camera;
public bool Rotate;
protected Plane Plane;
public float DecreaseCameraPanSpeed = 1; //Default speed is 1
public float CameraUpperHeightBound; //Zoom out
public float CameraLowerHeightBound; //Zoom in
private Vector3 cameraStartPosition;
private void Awake()
{
if (Camera == null)
Camera = Camera.main;
cameraStartPosition = Camera.transform.position;
}
private void Update()
{
//Update Plane
if (Input.touchCount >= 1)
Plane.SetNormalAndPosition(transform.up, transform.position);
var Delta1 = Vector3.zero;
var Delta2 = Vector3.zero;
//Scroll (Pan function)
if (Input.touchCount >= 1)
{
//Get distance camera should travel
Delta1 = PlanePositionDelta(Input.GetTouch(0))/DecreaseCameraPanSpeed;
if (Input.GetTouch(0).phase == TouchPhase.Moved)
Camera.transform.Translate(Delta1, Space.World);
}
//Pinch (Zoom Function)
if (Input.touchCount >= 2)
{
var pos1 = PlanePosition(Input.GetTouch(0).position);
var pos2 = PlanePosition(Input.GetTouch(1).position);
var pos1b = PlanePosition(Input.GetTouch(0).position - Input.GetTouch(0).deltaPosition);
var pos2b = PlanePosition(Input.GetTouch(1).position - Input.GetTouch(1).deltaPosition);
//calc zoom
var zoom = Vector3.Distance(pos1, pos2) /
Vector3.Distance(pos1b, pos2b);
//edge case
if (zoom == 0 || zoom > 10)
return;
//Move cam amount the mid ray
Vector3 camPositionBeforeAdjustment = Camera.transform.position;
Camera.transform.position = Vector3.LerpUnclamped(pos1, Camera.transform.position, 1 / zoom);
//Restricts zoom height
//Upper (ZoomOut)
if (Camera.transform.position.y > (cameraStartPosition.y + CameraUpperHeightBound))
{
Camera.transform.position = camPositionBeforeAdjustment;
}
//Lower (Zoom in)
if (Camera.transform.position.y < (cameraStartPosition.y - CameraLowerHeightBound) || Camera.transform.position.y <= 1)
{
Camera.transform.position = camPositionBeforeAdjustment;
}
//Rotation Function
if (Rotate && pos2b != pos2)
Camera.transform.RotateAround(pos1, Plane.normal, Vector3.SignedAngle(pos2 - pos1, pos2b - pos1b, Plane.normal));
}
}
//Returns the point between first and final finger position
protected Vector3 PlanePositionDelta(Touch touch)
{
//not moved
if (touch.phase != TouchPhase.Moved)
return Vector3.zero;
//delta
var rayBefore = Camera.ScreenPointToRay(touch.position - touch.deltaPosition);
var rayNow = Camera.ScreenPointToRay(touch.position);
if (Plane.Raycast(rayBefore, out var enterBefore) && Plane.Raycast(rayNow, out var enterNow))
return rayBefore.GetPoint(enterBefore) - rayNow.GetPoint(enterNow);
//not on plane
return Vector3.zero;
}
protected Vector3 PlanePosition(Vector2 screenPos)
{
//position
var rayNow = Camera.ScreenPointToRay(screenPos);
if (Plane.Raycast(rayNow, out var enterNow))
return rayNow.GetPoint(enterNow);
return Vector3.zero;
}
private void OnDrawGizmos()
{
Gizmos.DrawLine(transform.position, transform.position + transform.up);
}
#endif
}
@Kudoshi
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Kudoshi commented Mar 24, 2021

Added functionality to :

  • Restrict camera zoom in out
  • Camera pan speed

@Hashdow
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Hashdow commented Aug 31, 2021

Thanks

@Dieza91
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Dieza91 commented Sep 17, 2021

hi, thnx for the code, if i need to move around an object the camera, how can i do it?,

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ghost commented Oct 15, 2022

can u please add pane movement slowly stop

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