Question How to use sprite mask with trail renderer?

Is there any way to use sprite mask on trail renderer? I only want my trail to visible when it is on some specific sprite renderer, sprite mask fits this description, too bad it isn't worked with trail renderer . I'm making a 2d game and currently using URP in Unity 2020.

 

In the end, I use a second camera with a render texture to achieve this. First, create a camera and a raw image with the same size as my material, then output the camera view to the raw image through a render texture (I do this through code at runtime). Also, remember to set the culling mask of the camera to the trail renderer's layer.

Code (CSharp):

1.  
2.     private void Start()
3.     {
4.         renderTex = new RenderTexture(size.x, size.y, 0);
5.         renderTex.Create();
6.         camera = new GameObject("Window Camera", typeof(Camera)).GetComponent<Camera>(); // I create a new game object with a camera rather than add it to the current object because I need to set the camera's pos to (0, 0, -10).
7.         camera.transform.parent = transform;
8.         camera.transform.localPosition = new Vector3(0, 0, -10); // Offset the z coord so that the camera can see stuff
9.         // Set the camera to be 2d
10.         camera.orthographic = true;
11.         camera.orthographicSize = transform.localScale.x / 2;
12.         camera.cullingMask = LayerMask.GetMask("Your Layer Here");
13.         camera.forceIntoRenderTexture = true; // I don't really know if I need this line, but didn't test it yet.
14.         camera.targetTexture = renderTex;
15.         image = GetComponentInChildren<RawImage>();
16.         image.texture = renderTex;
17.         image.canvas.worldCamera = camera;
18.     }

 

Hi,

I installed Unity version 2022.1.0b7 which includes this function but it's not working the same way as on particles. For simplicity I created an object with a particle system and a trail renderer both set to 'Visible outside mask' but it seems the trail renderer ignores the mask. Is there anything else I should set for it to work?

Thanks in advance

 

Hi. There is a way to make the trail render as a mask of an image? I want an "eraser" effect but mixed with the trail effect, so the "erased" part will be reconstructed after a while. Thank you.

 

Where is this setting located? I can't seem to find it on my Trail Renderer component... Neither can I get the code example to work. Help would be greatly appreciated

 

Thank you!

 

Hi Richard,
Is this then also something that can be added to LineRenderer? That would be wonderful for us and future generations Thank you.

 

Can this backport to 2021.3? Really need this feature when render TrailRenderers in UI.