Serious issue with Sprite Renderer and animations that update material properties on them

[dean-cgs]

There is a quite serious issue that is easy to reproduce when animating material properties on sprite renderers in Unity 6.

If you have multiple sprites with an animation that modifies any properties on a material - which is quite a common thing to do - the sprite renderer glitches out and shows the incorrect sprite.

Moving the camera often highlights the problem, but I’ve had it with static cameras too.

I’ve created a small basic project on GitHub along with instructions on how to reproduce the issue:

GitHub - DeanIsseyegh/unity-6-sprite-render-issue: Very basic project showcase a...

The problem happens with both the Sprite-Lit-Default shader and with any custom ones based on it.

This is a very common thing to do in a Unity project, and this bug is consistent and easy to reproduce.

I’ve submitted a bug report and also found these forum posts which I believe are explaining the same issue:

Shader bug (Damage Flash Shader)

I’m using this simple shader: “https://www.youtube.com/watch?app=desktop&v=rq6yGh-piIU” [bugGIF] The FlashAmount value is updated by the characters’ damage taking animation. The error with the sprites happens when I have 3 characters, in the gif above I deactivate one of the characters and the error stops happening

Animating Material Property Causes Issues with 2D Renderer

I’m in the process of upgrading our 2D project (using 2D renderer) to Unity 6 and I’m discovering new rendering issues. If you animate material properties (e.g. via an AnimationClip), the renderer will often render the incorrect sprite. Scene with 3 sprites [Scene with 3 sprites] At runtime, the rendered sprites are incorrect. Moving the camera changes which Sprite is displayed. The green flash is a simple animation on a 2D shader. [At runtime, the rendered sprites are incorrect. Moving th…

Some interesting observations are:

• Turning a game object in the hierarchy on/off at run can sometimes fix the issue.
• Creating a script with an Update loop that updates a material property using either MaterialPropertyBlock or just SpriteRenderer.material.SetColor() does not display the same issue

[msfredb7]

It was confirmed and solved, here’s the bug tracker:

Unity IssueTracker - 2D Renderer Breaks When Animating Material Property with...

[dean-cgs]

Awesome, thank you!

It does not seem like the bug has been solved (yet), but hopefully it does get fixed soon as its a blocker for us upgrading to Unity 6.

[msfredb7]

I think it’s been solved internally. The fix is awaiting review/approval.

[dean-cgs]

Know if there are any updates on the bug? The fix is still labelled as “In Review” and has only been released in a 6000.1 alpha version.

[MichelVictor]

This bug hasn’t been fixed yet, still happenning, manly when 2 or more of the same sprites are in the screen and one of them is on the edge.

[CorgiCabal]

Here’s another one @Venkify

@MichelVictor There’s a bugs kinda like this in progress though this is possibly new

[Venkify]

@CorgiCabal

@MichelVictor There’s a bugs kinda like this in progress though this is possibly new

We have fixed this issue, tested the fix and its currently in the process of landing in 6000.2
Will start backports once it lands.

@MichelVictor
Please feel free to submit a repro project, so we can confirm the same for the above.

Apologies for any inconvenience this may have caused.

[MichelVictor]

@Venkify

We have fixed this issue, tested the fix and its currently in the process of landing in 6000.2
Will start backports once it lands.

Does this mean that after it works in 6.2, you will implement it in the next LTS versions, or will it still take some time?
We are about to release a demo and need to know when it will be fixed, as it currently cannot be launched as it is.

[apparition]

If your issue is related to the issue I reported I might have some suggestions for you… My issue is here:

Dynamic draw call batching seems to mix up sprites between SpriteRenderers at random

I’m seeing a strange intermittent rendering issue with SpriteRenderers in URP. I mention URP specifically because I’m converting my game over from the Built-In Renderer and I didn’t see this issue there. When I have multiple SpriteRenderers on screen using the same material, Unity seems to render them in a single dynamic draw call* (based on the “Draw Dynamic” item I see in the Frame Debugger). When it does this, it seems to occasionally, at random, combine SpriteRenderers that display differen…

The first thing I’d try is packing your sprites into a sprite atlas, but it looks like they might already be?

You can also try using different materials on each SpriteRenderer. Make duplicates of your materials (maybe you can do this automatically on Awake()?).

I’d also suggest disabling dynamic draw call batching but I haven’t figured out how to do this. There’s a checkbox for it in the URP settings but it had no effect when I tried it.

Anyway, not sure if any of this will actually help, but I thought I’d share.

[Venkify]

@MichelVictor

Does this mean that after it works in 6.2, you will implement it in the next LTS versions, or will it still take some time?

Please note that once the fix lands on 6000.2, we will backport to 6000.1 and 6000.0 within a week or 2 after testing the backports. Will keep this thread posted.