<udim>

[darloman]

hi,

Having the ability to load Mari textures on render time is awesome. However it is 10x slower than the same textures daisy chained together in maya (from local drive). When textures are stored on a server on a slowish network the scenes that use vray <UDIM> syntax in the file paths are not renderable at all. I assume that the textures are continuously being loaded from the drive and are not cached, to save memory. Is that assumption correct? Is there a way to use <UDIM> syntax and tell vray to pre-load them/cache in memory etc? Any other tricks I should know of?

cheers
Pawel

[yolov]

You can use the option to cache bitmaps between renders (render settings > VRay tab > global options) to speed up the consecutive renders.
Are the files you're loading very large? Do other large files load faster from a network?

[darloman]

hi Alex,

one texture (from the network) or the entire sequence of them, daisy chained in maya, render without any problems.
the moment I change the texture path to use vray syntax <UDIM> instead of the number (I do not allow maya to handle it, just pass that string to vray) my renders basically stop. A single bucket may take half an hour to render. The difference is just extraordinary. That's why I suspect that the texture is being loaded per ray from the file and is never kept in the memory. I do have quite a lot of them (like 64, 4k ones). But as I said they render with no issues if I allow maya to handle them in a daisy chain. Even when the textures are on a local drive the render is much slower when I use <UDIM> syntax in the texture file name.
The memory of the box is never even half used in both cases.
Windows 7, maya 2015 and a vray that is a week old (one of the nightly builds - 25693)
cheers

[yolov]

I'll do some tests here to see what might have gone wrong.
In the meantime - can you try the maya native udim tiling, vray supports that in 2015.
Textures should be loaded per bucket in vray, are you using a bucket sampler or the progressive sampler?

[darloman]

I use bucked sampler.
If I allow maya to handle the <UDIM> - ie maya will inject it into the path and set some funky expression on the node it doesn't work at all as far as I know. That was the reason I tried to sue native vray way of handling it. I will experiment with it again tomorrow.

[t.petrov]

What value have you set for the "Dynamic memory limit" setting?
Are you textures tiled (exrs or tiffs)?

In fact there is a texture cache in V-Ray and once loaded a texture will be kept in it (if there is enough free space of course) and not loaded multiple times.

[darloman]

dynamic limit is set to 5000 (mb). is it used in the same way regardless how I setup my texture inputs?
the textures I tried were tiffs. Not sure if they are tiled or not as they were supplied by another vendor.

btw I lied to you about vray version. I did my tests using official 3.0 release. I haven't tries it in the nightly.

[t.petrov]

Can you enable all messages in the log settings (Render Settings -> Settings -> Log message level -> all messages) and post the log?
I think the log can be found in the temp folder.