Grass not rendering properly

[Jillian]

Hello,

I love Gaia. It's such a great asset. 

I've been having an issue in Unity 2020 and 2021 where grass renders as flat white rectangles.

(Inserting an image from a URL wasn't working.)

https://www.dropbox.com/s/5m9fhli0jisn738/unity_gaia_grass.png?dl=0

 

Does anyone know what is causing this and how I can fix it?

[Peter]

Hi there, this is a known issue with grass in HDRP: Unity did not support grass rendering in HDRP for quite some time. We added our own grass rendering system called Flora in the Gaia Pro versions that will kick in as soon as you start the scene. So those white squares should disappear as soon as you run the scene if you have Gaia Pro.

In Unity 2021.2 they added a new grass rendering system for GPU instanced grass (Instanced Mesh mode) which you can utilize with Gaia as well, but we have not migrated our spawner configuration to use this new system yet. In the non-pro version you would need to setup Gaia to utilize an instanced mesh instead.

[Woopinator]

https://www.dropbox.com/s/q26dl3tjqwyqjb5/what on earth is this grass.jpg?dl=0 i am having problems with the grass in Gaia? if this link does not work.... Basically the grass is blurry as hell yet the flowers and everything else is fine it is just the grass 

[Bryan]

5 hours ago, Woopinator said:

https://www.dropbox.com/s/q26dl3tjqwyqjb5/what on earth is this grass.jpg?dl=0 i am having problems with the grass in Gaia? if this link does not work.... Basically the grass is blurry as hell yet the flowers and everything else is fine it is just the grass 

This could either be: 
1. Your Wind Speed for some reason is too high. 
2. Your Anti-aliasing needs to be set - I would try TAA or SMAA

[Woopinator]

10 hours ago, Bryan said:

This could either be: 
1. Your Wind Speed for some reason is too high. 
2. Your Anti-aliasing needs to be set - I would try TAA or SMAA

i will try this and get back to you, thank you. Wind speed was set to moderate.

[Woopinator]

unfortunately the above didn't work

[Bryan]

Is this the grass in one of the biomes? 

 

[Woopinator]

On 7/1/2023 at 8:35 PM, Bryan said:

Is this the grass in one of the biomes? 

Yes this is the apline meadow biom had tried a different biome and still same result

[Woopinator]

Yes this is the apline meadow biom had tried a different biome and still same result

On 7/1/2023 at 8:35 PM, Bryan said:

Is this the grass in one of the biomes? 

Yes this is the apline meadow biom had tried a different biome and still same result

[Bryan]

Ok thank you for this info, I am checking to see if I can reproduce this error. 

In the meantime can you please try and go to the flora manager, then click remove flora from scene. 
After make sure that you spawn the grass or that the grass is still in the scene. 
If you are using HDRP it will be the white planes. 

Then please try to re-add Flora to the scene and see if that fixes it. 

[Woopinator]

48 minutes ago, Bryan said:

Ok thank you for this info, I am checking to see if I can reproduce this error. 

In the meantime can you please try and go to the flora manager, then click remove flora from scene. 
After make sure that you spawn the grass or that the grass is still in the scene. 
If you are using HDRP it will be the white planes. 

iwliThen please try to re-add Flora to the scene and see if that fixes it. 

ok  will do this, i am not ment to have any pre-requisites for gaia ? like unity addressable or jobs or anything else am i?

 

[Bryan]

No there isnt. 

[Woopinator]

This did not work unfortunately, also the fps character controller seems to have stopped again, no changes where made and i can look but i cannot wander around.

 

[Bryan]

What version of HDRP are you using? 
Can you check the shaders on Flora and see if you are getting any red errors? 
Also can you please disable the post processing and see if it could be something related to that? 
 

[Peter]

@Woopinator I was testing a newer Gaia version in Unity 2023.1 and ran into the same issue. I found that this seems to be connected to HDRP motion blur - Motion blur seems to be enabled now in the newer HDRP versions when it was off by default before.
We still need to investigate why the Flora shaders produce this weird result when motion blur is enabled, can you please for now try to deactivate it in the Graphics settings here?

[Woopinator]

On 7/4/2023 at 8:09 PM, Peter said:

@Woopinator I was testing a newer Gaia version in Unity 2023.1 and ran into the same issue. I found that this seems to be connected to HDRP motion blur - Motion blur seems to be enabled now in the newer HDRP versions when it was off by default before.
We still need to investigate why the Flora shaders produce this weird result when motion blur is enabled, can you please for now try to deactivate it in the Graphics settings here?

i will attempt this thank you 🙂

[Peter]

Small update to this: We found that there must have been a change in how data is processed in shaders for instanced indirect rendered objects; we found the same issue with other instanced indirect rendered tech unrelated to Gaia. 
We checked with earlier unity / hdrp versions and there it is still possible to enable motion blur, so something must have changed.

[Woopinator]

9 hours ago, Peter said:

Small update to this: We found that there must have been a change in how data is processed in shaders for instanced indirect rendered objects; we found the same issue with other instanced indirect rendered tech unrelated to Gaia. 
We checked with earlier unity / hdrp versions and there it is still possible to enable motion blur, so something must have changed.

So turning off the motion blue settings off in HDRP did do the trick, but now they seem to have this weird flickering and the fps controller is still useless as i still cannot move around the terrain i can just look around with the mouse.

[Peter]

Hi @Woopinator, another update: We found evidence that Motion Blur is rather a symptom, than the cause. This thread here describes the issue and claims that certain rendering functions in Unity do not generate the motion vectors that are necessary to process effects like Motion Blur and TAA correctly.
What is strange though that those rendering functions seemed to have worked for us in earlier HDRP versions. The flickering that you were seeing was most likely also caused by this.
You can - for now as a workaround - switch off Motion vectors altogether in the HDRP Render Pipeline Asset:

This should get rid off the blurriness and the flickering, however it has the side effect that TAA will not work properly anymore, it will produce a blurry image when you move the camera. You would need to use a SMAA or FXAA as antialiasing method in the meantime.

Regarding the controls not working in the first player controller anymore: It is a bit difficult to say what the exact change was that made it stop working. You could check if:
 

• The input handling in the player settings is either set to "Old" or "Both"
  
  
   
• If there are key bindings defined in the Input manager for forward, backward, etc.
  
  
• If there is a controller connected maybe that interferes with the keyboard input
• If you are familiar with scripting and debugging, you could consider looking into the first person controller scripts to see if the input really "arrives" there when you press a key. A good starting point for this would be the function "GetInput" in the FirstPersonController.cs script, would be interesting to see what the input for the horizontal / vertical axes are when a button is pressed:
  
   

[Woopinator]

So fps controller is again fixed after starting a new scene and re-applying the fps controller through gaia, the flickering i will try your mentioned method everything else seems in good order now so thank you guys! i hope that unity are able to fix the cause.

[Bryan]

Thank you for the update! 

[Peter]

Hi @Woopinator, another update: We found this issue happens not only with Flora, but with the native unity terrain detail system as well in HDRP - all it takes is that the terrain is not positioned at 0,0,0. So even without Gaia involved you can run into this bug as long as you are using terrain details in HDRP and your terrain is not at 0,0,0.
We contacted unity to get this resolved.

[John Reynders]

Hi! 

 Many thanks for the thread above with the thorough problem-solving. I was seeing exactly the same issue - using Unity 2023.1.4f, HDRP 15.0.6, and Gaia Pro 2021 v340. The steps above navigated the issue. 

 Cheers! 

   -john

[Bryan]

Thank you for the info! 
Glad its working! 

 

[Bryan]

Unity does have a bug tracker sometimes they do get to fixing it, but it just depends. 
Not everything gets fixed in the same version.