Is it possible to have transparents using the 2D renderer in URP?

Hi! I started using the URP for the 2D lights package and it's been really enjoyable so far. However, I'm unable to make a screen-space distortion effect (which utilizes a custom shader on a hopefully transparent object) with the 2D renderer that's necessary to use if you want the 2D lights & shadows. I want to know if it's possible, which it really seems like it should be, but I can't figure it out.

My main question is, how do I mark an object as transparent for the 2D renderer in URP?

I'm able to get the screen-space distortion effect with a Forward Renderer instead by following this tutorial. With a Forward Renderer you can make a new layer and then specify that layer to render after the others inside the "Render Features" settings, which doesn't appear to exist with a 2D renderer. But the problem with using a Forward Renderer is that 2D lights & shadows don't work anymore.

As a different workaround for getting the same effect while using the 2D renderer, I've also tried to have the shader run directly on the camera by using this script attached to the camera, but it doesn't seem to do anything:

Code (CSharp):

1. public class ScreenWideEffect : MonoBehaviour
2. {
3.     public Material material;
4.  
5.     public void OnRenderImage(RenderTexture source, RenderTexture destination)
6.     {
7.         Graphics.Blit(source, destination, material);
8.     }
9. }

Here's the shader graph I'm using, if it helps:
1 - the shader for an object I wanted to make transparent and put in the scene on top of other stuff
2 - slightly modified to take in the _CameraOpaqueTexture, so it can distort that and blit to screen

I also tried setting up both a 2d renderer and a forward renderer but I can't seem to get the 2d renderer to render my should-be-transparent object as a big grey square. Which makes sense because I couldn't find a setting that looked like it should tell the renderer that object is different and should be rendered afterwards.

So my questions are, in order of importance,
A) Is it possible to make a transparent object with the 2d renderer?
B) Is there some other way to get a screen space distortion effect while using a 2d renderer?
C) Alternately, is it possible to get 2D lights & shadows without using the 2d renderer?
D) What am I doing wrong with my OnRenderImage() script above, or with my multiple-renderer setup?

 

Awesome, thank you so much! The only thing I had found was this: https://forum.unity.com/threads/mul...for-weeks-and-cant-find-info-solution.803766/ where the suggestion was to fork the 2d tenderer and write your own thing which seems WAY harder.

 

Sorry to hijack I'm just confused by the answer to A). It's not possible to make a transparent object with the 2D renderer? Aren't all sprites by default on the transparent render queue, or am I misunderstanding the question?

 

If I understand correctly, you're right that all sprites are on the transparent render queue by default.

What my question should've been is something like "is it possible to make a sprite that will render after the other sprites" to which the answer is no.

 

Ah yeah. I was hoping with SRP we'd be able to basically script it so we'd basically be able to make our own version of _CameraOpaqueTexture at a custom moment in the pipeline. Essentially like grabpass in the built-in render pipeline except not as devastating performancewise.

 

Hello!
Any news by any chance on this?
Currently on 2019.3.5f1 and marvelled at how well 2D Renderer works with composite shadow casters and all even in low-ish end devices.

However, was interested in this very same feature, wondering if it is coming soon or already implemented in further versions.

Would rather go with A. and be done with it (if it is to be implemented anytime soon) or go the Scriptable Renderer Features (if it is to be implemented also) and have control on 'when' to create the opaque (or equivalent) texture for the sprites.

B. would work, however it requires a bit of a dual camera setup to make the post processing effects work on a final rendered texture (the mix of a first camera RT base fullscreen sprite, the distortion effects overlaid, let the pipeline work post effects like bloom and vignette and others). Certainly not that complicated and on the easy side to do but would be the last option.

Thanks a lot in advance.

 

Hello, if OnRenderImage() is not supported, what is alternative in URP 2DRenderer?

 

I'm extremely interested about this, that last message really made my heart beat (I have been googling regularly to see if this will be implemented for a very long time now), I just checked and I assume that it didn't make it through yet? Anyone knows anything about this? @Chris_Chu ?

 

Nothing about it in the 2020.1 or 2020.2 release notes.

 

Why is it called _CameraSortingLayersTexture if it's just the opaque render target? It probably should get called whatever it's largest use-case might be, or by what it actually is... that name doesn't really leap out to developers wanting an opaque texture if skimming any (eventual) docs.

 

"There are no plans to support _CameraOpaqueTexture. We have instead created a new shader variable called _CameraSortingLayersTexture which will contain layers rendered from back to front, up until a specified layer. The upcoming release of URP 11 should have it." -Chris_Chu from another thread.

 

Yeah I get that, but it is also compatible with just the one layer, so it's basically describing potential usage instead of what it actually is as an object.

Not an issue for me, was just feeding back.

 

Thanks for the explanation, I guess it's no problem if it's documented.

 

Would this mean it would be possible to emulate the current GrabPass functionality for transparents by using _CameraSortingLayerTexture?

As in would it be possible to specify multiple sorting layers during the rendering process and saving each into a texture? Or is it limited to only 1 specific sorting layer using only that 1 built-in texture variable?

 

thanks for the info @Chris_Chu , super happy to see Unity giving this some love, unfortunately I don't see to be able to make it work, This is literally the only thing that shows up on google when searching for this new variable so I'm sure that a little step by step guide will benefit the whole community for years to come as it is likely to stay up there.

I have a test project that is working with CameraOpaque and Forward renderer, when I replace the CameraOpaque variable for the one you mentioned and change my forward renderer for the 2D renderer I can see the effect working in the preview window of shader graph (just like I could see the effect of _CameraOpaqueTexture) but in game I get the same result that _CameraOpaqueTexture were giving me with the 2D renderer (working fine with the other renderers), only the colour changes (just a semi-transparent black sprite), any chance of getting a little git sample where this node is up and running? This is how I have this set up:

in my shader graph (which seems to display the correct effect), I just put this variable in the node as a texture where I use to have the camera opaque one (tried with both, and 's' and without an 's' at the end, noticed that you mentioned both):



then in the renderer I turn it on, pointing to a default layer:



my background is opaque (in the default layer):



the sprite with the _CameraSortingLayerTextures material is transparent (it is also in the default layer):



tried experimenting with different values but nothing seems to bring it back to live, am I missing something?

thanks for your time!

 

spent another hour today trying to get this to work, I'm either missing something or _CameraSortingLayersTexture doesn't do anything. Set up a glass effect with Camera Opaque is super easy, but _CameraSortingLayersTexture just makes the sprite black

 

I think I'm having the same problem in 2021.1.0b8. My shader tries to use _CameraSortingLayersTexture as a global texture variable and all it gets is a default grey square, no matter how I set it up in the Renderer 2D Data.

I'm also wondering if there are plans to allow setting up multiple blit passes like these? I'm hoping to convert a big 2D project from Built-in to URP as the performance gains are truly massive, but in a lot of places we use 2, sometimes 3 grab passes and there seems to be no way to replicate that in URP.

 

Hi, any news on this ? I can't make it work either; it gives me a grey texture

_CameraSortingLayersTexture is indeed recognized but don't seem to work

 

I was strugging with it for a while as well and then came across another thread where I found solution for me.
Adding a single light object into the scene made my shader work for me.
Also make sure that the exposed parameter is unchecked for the _CameraSortingLayerTexture.
And the parameter I used is as mentioned above _CameraSortingLayerTexture.

 

I tried the solution mentionned by KristoE and the texture now "work" but look very buggy (see attachments).
Maybe I am just not using it correctly

 

thank you for letting us know @Carbone_13 after setting everything up I got it "working" it seems to be a little buggy but works more than less on play mode, I needed this feature back so much, if someone else lands here full instructions about how to set it up: https://forum.unity.com/threads/current-2d-renderers-missing-core-features.1023772/

but it only seems to work if I set my node as "Lit", couldn't get any result with "Sprite Lit"

 

Looks like there is a typo in the tooltip for this feature. You need to use _CameraSortingLayerTexture (like mentioned above) instead of _CameraSortingLayersTexture as mentioned in the tool tip. Drop the "s" in your shader and you should be good.


This worked for me.

 

The issue you are having seems to be with trying to include the screen rendering image into the image itself.
Try setting the sprite with the shader to the highest drawing layer, this should remove the glitching. If for your use case you need it behind, then I guess you need some clever masking to make that work.

 

This is working incredibly well. I have set up a heat distortion, blur and underwater shader all completely working in the 2D pipeline. It's so great bring able to just place a heathaze sprite Infront of all the stuff I need to effect and it just works...

My only problem is you can't have multiple _CameraSortingLayerTexture sorting layers.

Is it possible to create a list of _CameraSortingLayerTexture and be able to set each to different layers and then reference them individually in the shader graph? This would really open up the opportunities for a vast number of effects.

Thanks Chris for your hard work.

 

I am trying many ways but I can not create a sprite object that distorts my objects behind it using URP 2D Render Data and Scene Color node in shader graph. Does anyone know how to get this effect? Any examples or tutorials?


result

 

There's a demo here: https://github.com/Unity-Technologies/2d-renderer-samples/tree/21.1

Look for Camera Sorting Layer Texture.

 

Thank you @Lo-renzo for the great examples. Unfortunately, I have not found an answer on how to deal with the distortion effect in the particle system using URP & 2 Render Data. Could someone please help me and give me some guidance?

 

Hi, Chris!
Any news about this feature?

 

Works really well.
As mentioned above, steps to make it work:

• use _CameraSortingLayerTexture tag, remove the "Exposed" checkmark.
• In the 2D renderer data, set the "Foremost Sorting Layer" to the last layer you want to be renderer with distortion.
• Set the "Sorting Layer" of the sprite renderer which contains your distortion material to be above the last layer of the "foremost sorting layer".

Cheers

 

Thanks @RedHillbilly for the tips, however, I can't seem to get mine working despite the setups. My sprite just shows a black material that sometimes flickers different colours depending on the camera zoom instead of a distortion material. I'm not sure if I am doing something wrong in my setup.

Could someone help me identify the errors if I have made any?

2D Renderer Data setup:


URP Pipeline Asset setup:


Shader setup:

Result:

 

Hi, sorry to revive this thread, but adding support for multiple CameraSortingLayerTextures would be a great addition to the feature imo.
In our case we have multiple effects like blur we want to apply to parts of the game world and this would allow us to stack them on top of each other. Otherwise we would have to make sure the effects don't overlap or use an additional camera (which renders into a texture). Is this something you are considering?

 

Hi!

Just here to say that having multiple CameraSortingLayerTextures would be awesome indeed!

In my current project, I want to blur the background depending on conditions, and I also want a heat distortion effect. As of now, I have to make a blur version of my background texture and fade between them. Is the legacy render pipeline, it was just a shader and was much more convenient!

I hope to see this in the release notes in the future

 

I also think that this feature would be much more useful if it had the option for multiple CameraSortingLayerTextures.

 

Could anyone lay out exactly how to get transparent sprite effects working using unity 2021.3.1.0f1 or later, and using the Renderer 2D? I don't understand exactly how the shader, renderer, and camera should be set up. I just want to have 2D lights and effects (such as heat distortion) working at the same time.

I can't find info about this anywhere else, so your time is appreciated.

 

Hi, i've been trying to achieve distortion effects while using URP 2D renderer, my project uses 2D lights, trying to apply a 2D distortion effect results on a gray square. This is the shader i'm using

As you can see this is a simple shader, 'been following all the steps on this youtube tutorial
This tutorial uses the forward render pipeline and i'm trying to achieve this using the 2D render pipeline as i said before.

I have the 2D render pipeline settings like this




I would like to know if is there a way to achieve distortion effects, or directly, making the scene color node work
using the 2D render pipeline, I've been MONTHS looking for a solution but didn't found anything and there is no solution in the docs, or any forum with a simple or complete solution or explanation on how to get distortion FX on a project with 2D Lights



@Chris_Chu , @RedHillbilly , @yuanxing_cai

anyone can make a detailed explanation on this topic? Never needed so much help before, Thanks for the attention ^^

 

@oscurekid There are a couple problems.

1. Forward Renderer Data vs 2D Renderer Data. Look at your Renderer List on the Universal Render Pipeline Asset. It lists the New 2D Renderer Data. Simply put, you do NOT want Forward Renderer Data. You can delete it. You're adding your Renderer Feature to the Forward Renderer Data, not the "New 2D Renderer Data" asset. Even if you added your Renderer Feature to the correct asset, it still wouldn't work and is also unnecessary.

2. You're using Scene Color in your Shader Graph. You do NOT want that. The 2D Renderer does NOT create a _CameraOpaqueTexture, which is what the Scene Color pulls from. The 2D Renderer doesn't use opaques, just transparents, so that's why the special _CameraSortingLayerTexture was developed. It takes a snapshot of the colors on your screen at a particular Sorting Layer of the transparent render pass.

------

How to fix so it works in shader and is populated (with a non-gray texture!) by the 2D Renderer.

(A) Fix your Shader Graph. Add a new Property on the Blackboard called CameraSortingLayerTexture and make sure its reference is _CameraSortingLayerTexture exactly. Then UNCHECK Exposed. This tells Unity to pull this property from a global texture, which is exactly what we want. Then sample your CameraSortingLayerTexture, replacing SceneColor. Plug in your distorted UVs into the UVs of the Sample Texture2D node.

(B) Fix the creation of _CameraSortingLayerTexture. On the 2D Renderer Data (for you, "New 2D Renderer Data"), go to the Camera Sorting Layer Texture section and choose a Sorting Layer. This sorting layer is when the snapshot of the current screen colors is taken. Create a Sorting Layer that's AFTER the colors you want to distort. The SpriteRenderer with your distortion material needs to have a Sorting Layer AFTER that snapshot or else you'll get the last frame's colors and it will be very weird.

So your scene will render in this order:
[some colors from background sprites]
[take snapshot of those colors @ Sorting Layer 2]
[distort that snapshot of colors @ Sorting Layer 3]
[anything else that renders after Sorting Layer 3]

For a working demo, check out the CameraSortingLayerTexture scene and folder here: https://github.com/Unity-Technologies/2d-renderer-samples/tree/21.1

 

Hi @Lo-renzo First of all, thanks for the reply.
The problem is: My 2D Render Data doesn't have that property

Already implemented your (A) But i cannot continue from there, can you point me in the right direction? Many thanks i truly appreciate the response ^^

Edit: Downloaded the example you pinned, copied the files into my project and change my renderer asset for yours, but is not working yet,
I would like to talk with you if possible, maybe i'm missing something. here's my discord tag:
Elven#0755

 

Aha, well that answers it. You must upgrade to a newer version of Unity. You need at least version 2021.1, but at this point go to 2021.3 LTS.

 

@Lo-renzo Many thanks! I was lost but thanks to you managed to have it working rn ^^

 

Hi @Chris_Chu . Is there a way to implement this silhouette effect behind objects with a 2D Renderer Data?

I tried following the same steps as this guide but using the CameraSortingLayersTexture you mentioned instead of the Opaque Layer Mask Filtering of the Forward Renderer, but is not working.

I Just want to know if there is any way to achieve this same silhouette effect behind objects using the 2D Renderer. Thank you!

https://docs.unity3d.com/Packages/c...ures/how-to-custom-effect-render-objects.html