A small correction regarding dolly zoom

Hi,
A minor correction in page https://docs.unity3d.com/Manual/DollyZoom.html for 5.5.

The C# example has no header, the unityscript example has a wrong header "C# script example", while under the unityscript example there is an orphan "JS script example" header.

Kind regards.
- Ippokratis

 

Well,
The c# script cannot compile as is since it throws some errors and warnings.
I attach here a corrected version, that is verified to work as expected, you can use it if you wish.

Code (CSharp):

1.  
2. using System.Collections;
3. using System.Collections.Generic;
4. using UnityEngine;
5.  
6. public class MoveCameraAlongView : MonoBehaviour
7. {        
8.     public Transform targetObject;
9.     public Camera targetCamera;
10.  
11.     private float initHeightAtDist;
12.     private bool dzEnabled;
13.  
14.     // Calculate the frustum height at a given distance from the camera.
15.     float FrustumHeightAtDistance(float distance)
16.     {
17.         return 2.0f * distance * Mathf.Tan(targetCamera.fieldOfView * 0.5f * Mathf.Deg2Rad);
18.     }
19.  
20.     // Calculate the FOV needed to get a given frustum height at a given distance.
21.     float FOVForHeightAndDistance(float height, float distance)
22.     {
23.         return 2.0f * Mathf.Atan(height * 0.5f / distance) * Mathf.Rad2Deg;
24.     }
25.  
26.     // Start the dolly zoom effect.
27.     void StartDZ()
28.     {
29.         var distance = Vector3.Distance(transform.position, targetObject.position);
30.         initHeightAtDist = FrustumHeightAtDistance(distance);
31.         dzEnabled = true;
32.     }
33.  
34.     // Turn dolly zoom off.
35.     void StopDZ()
36.     {
37.         dzEnabled = false;
38.     }
39.  
40.     void Start()
41.     {
42.         StartDZ();
43.     }
44.  
45.     void Update()
46.     {
47.         if (dzEnabled)
48.         {
49.             // Measure the new distance and readjust the FOV accordingly.
50.             var currDistance = Vector3.Distance(transform.position, targetObject.position);
51.             targetCamera.fieldOfView = FOVForHeightAndDistance(initHeightAtDist, currDistance);
52.         }
53.  
54.         // Simple control to allow the camera to be moved in and out using the up/down arrows.
55.         transform.Translate(Input.GetAxis("Vertical") * Vector3.forward * Time.deltaTime * 5f);
56.     }
57.    
58. }
59.  
60.  

 

this works nicely, but when i use the arrow keys to dolly in and out it's jumpy, not smooth. any ideas?

 

omg, kinda dig this issue out of the tomb. It seems still to remain as a prob on the page though. Thank you for this fix.

 

Still relevant in 2021!