Max. MipMap Resolution

[david.anastacio]

Hi,

Could any of the devs or QA explain how this feature (Max. MipMap Resolution) works exactly? The help page does not contain any info about this: https://docs.chaosgroup.com/display/...NI/Options+Tab
If I'm using a .tx or tiled EXR at 4k resolution, does this setting at zero forces V-Ray to always use the highest resolution? And how does the other values works, does 1 correspont to half resolution (2K)?



Bonus question:
In the "Raycaster" help page it says that the "Dynamic Memory Limit": "Geometry and EXR tiles share the same memory pool, so this parameter also controls the memory limit for tiled EXR files with mip-maps." So how does this work with .tx textures? Or .tx are not really supported?

Best,
David.

[david.anastacio]

Hi again,

Actually the "Dynamic Memory Limit" parameter doesn't seem to be working correctly.

We have a big asset here with lots of UDIMs (over 200) and baked textures.

No memory limits and no conserve memory:
Gray shade: 17gb
live shaders: 41gb
baked .tx: goes over 120gb
baked tiled exr: 108gb

With conserve memory ON, and 20gb on "dyn. Memory Limit" (20000mb):
Gray shade: 11gb (i guess conserve memory is working here)
live shaders: 35gb (i guess conserve memory is working here)
baked .tx: goes over 120gb (i guess the Memory limit doesn't work with .tx)
baked tiled exr: 90gb (this 10gb decreass is probably from the conserve memory, but it didn't limit the textures to 20gb)

The tiled EXR render should only take around 31gb (11gb from the geo and 20gb from the textures) or even less since the memory is shared by textures and geo. Why is it going over the limit???

Best,
David.

[david.anastacio]

Hi again.

chakarov and Gosho.Genchev, posted this 6 days ago and no answer....
Any idea why the "Dynamic Memory Limit" is not working with tiled EXRs??? This is becoming a more pressing issue as time goes by. The EXRs we created using the OIIO tool not the vray tool, but that should not make any difference.
And also, how does the "Max. MipMap Resolution" parametter works since no documentation on it can be found.

Best,
David.

[Gosho.Genchev]

Hey, David,

I apologize for the delay. If we don't answer right away, it means we don't know either and have to go through colleagues in other teams to figure out if there is a problem. If it's urgent for you, we'll try to fast-forward it.

The Max. MipMap Resolution parameter is an upper limit for the texture resolution.

[If I'm using a .tx or tiled EXR at 4k resolution, does this setting at zero forces V-Ray to always use the highest resolution? And how does the other values works, does 1 correspont to half resolution (2K)?

Currently (to my knowledge) there is no way to force V-Ray to use a specific mip-map level. It is always determined by V-Ray automatically, depending on the distance from the camera. So if the level is set to 0 and the camera is really close, V-Ray is free to use the highest resolution of the texture. If the level is set to 1 and the camera is really close, V-Ray can only use the second highest resolution.

I'll update the documentation today with a decent explanation.

Best regards!

[chakarov]

Any idea why the "Dynamic Memory Limit" is not working with tiled EXRs???...

You could control amount of memory consumed by textures with environment variable in houdini.env or with a post-translate script.
with environment variable:
VRAY_TEXTURE_CACHE = 7

with post translate:

[COLOR=#c0392b]import vray
renderer = vray.VRayRenderer()
textureCache = renderer.classes.SettingsTextureCache.getInstanceO rCreate()
if not textureCache:
     textureCache = renderer.classes.SettingsTextureCache()

textureCache.cache_size = 7[/COLOR]

in both maximum memory is set to 7Mb.
I will add a request to expose this setting in V-Ray ROP UI

[david.anastacio]

Hi again,

I apologize for the delay. If we don't answer right away, it means we don't know either and have to go through colleagues in other teams to figure out if there is a problem. If it's urgent for you, we'll try to fast-forward it.
Best regards!

Sorry but looked like thos thread was missed, since you guys are usually so fast getting back to questions and bugs

Gosho.Genchev, thanks for that additional info. That should also definitly be added to the V-Ray help page as this parameter is not even there right now.

chakarov, I will definitly give that a try. But why do you need to that doesn't really make sense, should't the "Dynamic Memory Limit" actually do that, the V-Ray manual clearly states that it controls the amount of memory used by tiled-EXR textures. Or does you request to add this "textureCache.cache_size" to the render ROP indicates that the Dynamic Memory Limit is not doing what it should?

Best and thanks for all the help,
David.

[chakarov]

Hello david.anastacio , docs page seems to not been updated. Memory limit for textures has a separate parameter, which is missing in VfH and will be added soon. You could use the post-translate script from my previous post, which is doing the same, or to set it globally with an environment variable. Docs page will be update as well.

[chakarov]

Texture Cache Size parameter is added in V-Ray ROP > Renderer > Options > Textures , value should be in MB.

[david.anastacio]

That's great to hear, thanks chakarov