How to Change Depth of Field: Focal Length from a Script (LWRP)?

Question

I would like to change the focal length of a Depth of Field effect when I select an object in the game (using Unity 2019.2 with LWRP).
I'm thinking I would use Post Processing Volume as a game object, with the Depth of Field effect enabled.
The script would use: using UnityEngine; using UnityEngine.Rendering.PostProcessing;
Then I would create a variable of some type, and set it to hold the data of Post Processing Volume, but I cannot find the type in the Unity documents.
Then I would do something like: myVar.focalLength = myNewValue;
I don't know if focalLength is the proper name, because I can't find that in Unity docs either.
Does anybody have a script for something like this?

Answer 1

It's a catchy thing. There could be more than one Volume blending at a time.

You need PostProcessLayer (it is should be in your Camera)

 public PostProcessLayer  v2_PostProcess;

Then you should go through active Volumes:

             List<PostProcessVolume> volList = new List<PostProcessVolume>();
             PostProcessManager.instance.GetActiveVolumes(v2_PostProcess, volList, true, true);
             //
             foreach(PostProcessVolume vol in volList)
             {
                 PostProcessProfile ppp = vol.profile;
                 if (ppp) 
                 {
                     DepthOfField dph;
                     if (ppp.TryGetSettings<DepthOfField>(out dph))
                     {
                         dph.focusDistance.value = REQUIRED_DISTANCE;
                     }
                 }
             }

Focal distance should be changed.

Answer 2

Hey, thanks! This worked!

Here's what I did:

I have FirstPersonCharacter (which is the camera).
I have a second game object that is the Post-process Volume (this comes in automatically when you start a new project in the LWRP template).
I used the code you gave me in a script (see below.)
I put the script onto the Post-process Volume.
I dragged the camera object into the public V2_Post Process field in the inspector.

So, thank you very much!

As bonus work, once you'd set me on the path, I also searched through the two scripts DepthOfField.cs and DepthOfFieldComponent.cs and found the names of the other Depth of Field properties, so now I can also address those in that same script (see it below).

So, with this information I can now do things like, when the camera moves, apply a blur to the Camera, and when it stops set the focus length back to normal to clear up the picture. By the way, the name of my script / class is LERP_Focal_Length.cs, but there is no lerp function in it (yet). That's the next objective, so hopefully nobody is confused by that name.

Script: using System.Collections; using System.Collections.Generic; using UnityEngine; using UnityEngine.Rendering.PostProcessing;

public class LERP_Focal_Length : MonoBehaviour {

 public int blur_amt = 1;
 public PostProcessLayer v2_PostProcess;

 // Start is called before the first frame update
 void Start()
 {
     

 }

 // Update is called once per frame
 void Update()
 {
     List<PostProcessVolume> volList = new List<PostProcessVolume>();
     PostProcessManager.instance.GetActiveVolumes(v2_PostProcess, volList, true, true);
     //
     foreach (PostProcessVolume vol in volList)
     {
         PostProcessProfile ppp = vol.profile;
         if (ppp)
         {
             DepthOfField dph;
             if (ppp.TryGetSettings<DepthOfField>(out dph))
             {
                 //dph.focusDistance.value = 69;
                 //dph.aperture.value = 30;
                 dph.focalLength.value = blur_amt;
                 //dph.kernelSize.value = KernelSize.VeryLarge;
             }
         }
     }
 }

}

How to Change Depth of Field: Focal Length from a Script (LWRP)?

2 Replies

Your answer

Follow this Question

Related Questions