Question Object closest to the finish line

I am advancing the objects in my scene with Add force. I focus the camera on the object closest to the finish line. Can you suggest a solution that will cause me fewer problems in terms of performance, where I can calculate the distance of objects from the finish line? Having many objects in my scene creates a problem.

 

how many objects you have? and can you check with Profiler, what is the slow part?
On which device this is running or targeted?

Or can you show your current script that calculates the distances?

 

As the game progresses, the number of objects on the screen can reach 300. My game will be for mobile platforms. I experience the largest performance drop after my object count reaches around 200. Objects that I instantiate are causing this problem. But I also want to get the best performance when calculating the distance.

Code (CSharp):

1. void FindClosestBall()
2.     {
3.         Ball[] balls= FindObjectsOfType<Ball>();
4.         Transform closestTarget = null;
5.         float maxDistance = Mathf.Infinity;
6.  
7.         foreach(Ball _ball in balls)
8.         {
9.          
10.          
11.             Vector3 directionVector = transform.position - _ball.transform.position;
12.             float targetDistance = directionVector.sqrMagnitude;
13.  
14.             if(targetDistance < maxDistance)
15.             {
16.                 closestTarget = _ball.transform;
17.                 maxDistance = targetDistance;
18.             }
19.  
20.         }
21.         _target = closestTarget;
22.     }

 

this line is probably the slowest one,

Code (CSharp):

1. Ball[] balls= FindObjectsOfType<Ball>();

so instead of always searching them, try something like:
- keep list/array/dictionary of spawned objects (when you instantiate, add to list, when you destroy, remove from it)
- or, if objects are spawned under parent transform, can try looping the children https://docs.unity3d.com/ScriptReference/Transform.GetChild.html

Even better if objects are moving on a plane, in 1 direction,
then could just compare X or Y or Z value directly (who is closest has biggest value, without measuring (full 3d) distance)

ps. can embed code with https://forum.unity.com/threads/using-code-tags-properly.143875/