Graphical errors with HDRP Motion-Blur

When i have hdrp-motion blur activated, it leads to a glitch-like flittering back and forth on models.
The movement is the camera rotating around an object. Its the CinemachineFreeLook component. The flicker does not only appear on the model that is the target of focus but also round them. It seem to be related to the rotation.

• Unity 2019.3.4f1
  
• HDRP Version 7.18 & 7.3.1 tested.
  
• Glitsch exists on both an imported model and the HDRP example hammer.

 

I still got the problem. I can't be the only person using HDRP-MotionBlur and CinemachineFreeLook, am i?

 

You are not alone. I have very similiar problem. No idea how to fix it though.

 

Feel you, same problem for 2019.3.5f1 and no idea what to do. For now I just put a very small value in the Volume Override so it's less noticeable.

 

I noticed in more recent HDRP versions, a lot (or all) of the post-process settings are enabled by default. I had to specifically place motion blur in my post-process volume override settings and set the motion-blur to zero in order to have no motion blur.

In previous HD package versions this was not necessary. I'm just throwing that out there, I don't know if it would fix your problem though.

 

I had this same problem https://gyazo.com/3f1bc843bcd0f265e25048592937e9fa
Unfortunately the camera rotation velocity only helped a bit, since it cannot go futher than 0.2.
Though, overriding the blur effect by deactivating it totally solved the issue.

 

did you just suggest that completely disabling motion blur is the solution to better motion blur? or do you mean disabling something else?

because i, (probably like everyone else) am also experiencing this issue. have been for the last year.

i can get convincing background motion blur, but no matter what settings i change, (even the secret cog settings), the slightest touch of my camera rotating around my player causes my player to look like its been sucked through a black hole.

so, has anyone found a solution to this problem yet? better question, is this considered "normal" for HDRP motion blur? i dont recall it being this bad before with the standard pipeline motion blur.

 

hi, does anyone who works for unity know how to get proper motion blur with HDRP? what settings do you commonly use? because a lot of us really need to know if our project is broken/glitched, and if we need to give up or find another solution.

 

that sounds great. better yet, is there a way to get REAL motion blur, instead of whatever this crap is doing?

like, for example, i dont know, cant we take 2 frames, maybe 3 or more, and just store them in a cache somewhere and interpolate between them, or something like that? or is that just too expensive? would at least fix the Z depth issues, not to mention this velocity thing.

or any way to get the lerp or whatever is going on to TRAIL BEHIND instead of pulling from both sides? can we get into the code to modify it?


I almost cant believe the intensity is at 1 either.



NOTICE BACKGROUND IS ALMOST NOT BLURY ^ ^ ^ camera rotating around player.


this would almost pass as good, if it werent for the fact that the camera is almost not moving at all. good for background, bad for foreground.

no matter what settings i try, i basically cant get the background and foreground to produce a realistic result. either one is off or not working and one is passable, then its the other way around. its pretty awful.

before i waste time filing a bug, is this NOT normal?

 

what you have provided in that screenshot is exactly what we want and expect from real-time motion blur. it sounds like you may not have run into what the rest of us are complaining about. we want the object in the middle of the rotation to not blur, while things around it, blurring very heavily. thats perfect. instead we are seeing the exact opposite. also, if i do manage to get something close to that, with the COG settings, the blur on the character jumps to black hole mode immediately after speeding up camera rotation just a touch. so very bad results that way as well.

also, if you notice, my first screenshot shows an intensity of 1 with 64 samples, but the problem persists; even with moving the camera slowly around the players. (ive tried two different players.)

i am using:

UNITY - 2019.4.14f1 LTS
HDRP - 7.3.1

i wont waste yours or my time trying to fix it in this old, LTS version of unity. it looks like it may be worth it to attempt upgrading yet again (which usually ruins my projects, but ill be sure to backup and try again).


question:

i notice that screenshot says 2021.1.0b, am i to assume this is a beta version? also, not very stable? is it not advisable to upgrade to this version? any idea the most stable release of both items with the latest motion blur settings? it looks like we need those extra settings, or at least should give a newer release a try, because, without an upgrade, what could fix the velocity data for the objects in the middle of the screen? can we tweak this ourselves?

 

update: I have noticed in the scene viewport, i can get proper motion blur rotating around the player IF i have the viewport MORE than a 16:9 widescreen ratio (like in your screen shot. id like to see if its the same in the GAME view). anything square or closer to vertical completely destroys the motion blur. so that seems to be part of the issue. BUT, this doesnt help the game window which stays glitchy no matter the ratio. strange.



here is an example of it almost working in the scene view, but checkout whats happening to that tree...

 

so i tried the new versions. it still looks terrible. you guys definitely need to work on it some more. specifically whatever is going on with the velocity data, and things directly in the middle of the camera rotation which are basically not moving at all, or very little, looking too blurry, no matter what settings i try.

 

im wasting too much time trying to get good results with HDRP motion blur. how are the motion vectors / velocity data calculated? is this world space position and rotation, or post screen space Z buffer type stuff?

have you confirmed your motion blur works on a 3rd person character? if so, is there any video proof of this? id like to see it, and your settings.

the closest thing i can get to usable motion blur on both first AND third person, is to clamp motion and rotation to the ridiculously low .02, which basically has the motion blur turn ON and OFF like a switch to a set low amount of blur, completely removing any dynamic acceleration of intensifying blur as the camera is moved or rotated more quickly.

any number higher than that completely breaks the effect. its unusable. if you can show me the effect working on a character, in a real world game scenario, i will provide a sample project for you to check. can we agree on that.

edit: there appears to be a problem with how the object movement motion blur and camera rotation/movement motion blur are computed together. i can get pretty good results with one or the other active (by as far as i can tell, disabling object motion blur with a max velocity 0 clamp), on a 3rd person player, but so far not together. and when one or the other is off, the background wont blur. so cant use this method.

 

Is motion blur in HDRP still an issue for users?