Having "Accurate velocities from vertex deformation" enables causes extreme blur on skeletal meshes

If you have any SceneCapture2D in your level and you have “accurate velocities from vertex deformation” in project settings enabled, all skeletal meshes look like this:

I was able to easily reproduce this in a new project.

Hello John,

I have created a SceneCapture2D as well as a render target. I then went through process of assigning target to capture and create a Material. I then assigned this to a cube in my scene. I brought in a skeletal mesh and placed this in front of capture.

In your description you have this :

72823-alttext.jpg

I do not see anything unexpected within my project. Could you post another screenshot and describe what you see and what you are expecting to see.

Hi ,

thanks for looking into this. screenshot was a link to a forum Attachement and worked fine here, I have now updated screenshot (uploaded image directly here on answerhub).

Have you enabled “Accurate velocities from vertex deformation”?

Yes, I have this enabled. I just ran a few more tests and I’m definitely seeing some issues. I’m not experiencing blurring but I am seeing some shadow popping on other meshes. popping is most obvious around back of skeletal meshes legs. other thing I noted was if you run in front of skeletal mesh camera will zoom in very close to active character.

I will investigate further and get back to you.

I guess it’s best to just send you repro project:

https://.com/file/d/0BzqDz_3FVfpOQUkwZ19FNWhFTFk/view?usp=sharing

Are you sure camera zoom is any different if “Accurate velocities from vertex deformation” is disabled?

issue is a lot worse in standalone, so make sure to run game in standalone and not in PIE.

Thanks for test project. This is a screen shot from your project played in stand alone PIE.

Interesting. So you don’t see blur. Then its probably depending on hardware. I use a i7 5820k and a R9 390. You probably use a Nvidia GPU, could you try to run project on a AMD one?

So, we have tested this with a AMD graphics card setup. We do see this issue happening. There have been many ongoing issues that have involved AMD graphics cards. We have been communicating with AMD to ask for updates that will allow for many of issues we’ve tested to be addressed. You may be able to find more on AMD forums.

only other option that I can think of is to roll back a driver. Although I realize that with AMD this is not always an easy thing to do.

I can’t really tell 30% of players of my game to “Roll back a driver” just for my game, right? :wink:

And as far as I know there is no way to enable “Accurate velocities from vertex deformation” only on Nvidia GPUs. So I’ll have to keep it completely disabled until this is fixed.

Could you tell me what other “ongoing issues” there are so that if I run into one of them, I know they are AMDs fault?

I have entered a bug for this issue and it will be addressed by our development team accordingly. All issues reported are handled by our own internal system. If it is determined as an AMD specific issue then it will be handled through them. We do not have a list with issues that have been brought to AMD’s attention.

ticket number is UE-24905

Thanks for reporting this to us.

Thanks!

It seems bug does not only occur on AMD, someone downloaded my project and he sees bug, and he uses a GTX 770M GPU.

Hi , have you updated bug report with new information?

I have updated ticket to include other graphics cards experiencing blurring.

Hi , is there any update about this yet?

Hi John,

No update at this time. I’ve assigned myself to watch report and I’ll post here when I see any change. Thanks for your patience.

Thanks ! :slight_smile:

I had a similar issue (with scenecapturecube instead) that appears to be fixed in latest 4.11 preview 5.