Tile rendering a frame, or sequence in Vray..

[jasonic72]

Hey guys,

We have some larger res (6k) sequences coming down the pipe.
I was looking around for an option to enable tiling for my final rendered output, but no obvious parameters stands out in the Render Settings.

After searching around the board I've found some clues, but no exact explanation on how to aproach it.

Anyone have a sec to explain a straight forward workflow/implementation for tile rendering a sequence in Vray 2.0?
Can Vray render out tiles, and assemble the final results for us? Or will I have to restitch the final frames in comp.

(we're Maya (2012)>Vray(2.0)>Nuke around here.)

many thanks!

-j

[braveRabbit]

Just recently I started to include tile rendering with vray in our rendermanagement tool "Pipeline" (OSX only). It took me a while to figure it all out because there are some things that VRay likes to do differently than other renderers. I still might not be an expert on this but I will give it a shot.

Tile rendering only seems to be available through command line rendering. It utilizes the -reg flag and then it's time to figure out how to set the region borders. VRay starts in the upper left corner working it's way down, starting at 0.
So, rendering a 6K image would give you something like:
-reg 0 2999 0 1999
-reg 3000 5999 0 1999
-reg 0 2999 2000 3999
-reg 3000 5999 2000 3999

The major problems I had was with setting up the correct render output path, which obviously has to be different for all tiles so that they don't write over the previous image. Unfortunately VRay doesn't like to have an individual path set with the -imgFile flag that doesn't yet exist. And it's way too tedious to pre-create all the necessary file paths. My workaround is to use the maya -rd flag to define a render directory, because maya is smart enough to create a requested directory if it doesn't exist and let the render process take the file name from the maya scene file. The only drawback is that now all tiles go to their respective directories ../tile1, ../tile2, etc.

The command line could be something like:
render -proj <<PATHTOPROJECT>>/KIDS_3d -r vray -s 1 -e 50 -rd <<PATHTOPROJECT>>/images/tile3 -reg 0 2999 2000 3999 renderScenes/img_kids_179_flowers2.mb

I guess you could write a quick nuke script to pull all the tiles together automatically and stitch them. Don't know if there is an automatic function included in VRay but I doubt it.

If anyone knows of a better solution, I am all ears for that

Cheers, Ingo

[vlado]

Another option is to use full frame rendering, but:

*) Turn on the V-Ray VFB;
*) Set your image format in render settings to "vrimg";
*) After that, set the "Memory frame buffer" option in the Common tab of the render settings to "None".

When your render is finished, use the vrimg2exr tool to convert the result to an OpenEXR file.

You can use distributed rendering to speed things up.

Best regards,
Vlado

[jasonic72]

Thanks very much for the quick replies guys


A few quick questions for Vlado if he has a moment..

It sounds as thought I would be rendering locally to the VFB with this solution, can I utlize this same method on our render farm? (I ask as I'd feel better when rendering a sequence (under deadline) to mitigate the potential "single point of falure" scenerio a local render of many frames might offer).

Also, we're tending to output multiple independent Render Elements in conjunction with a established beauty render, so any solution would need to support outputting them. Hopefully we could do this with what you suggest here.


Many many thanks for the input and wisdom,

-jason

[tom_hh]

Hey, I reactivate this post since the topic is actually relevant for me. Tiled rendering is very useful, when rendering large images. Clients going crazy at the moment and want to have resolutions over 12k, up to 20k for still and advertising. Rendering an vrimg is not perfect because of the render time. When in the rendering process in the course later errors occur, the entire rendering aborts, if you render in tiles you have caches that can be seamlessly merged. If the rendering takes longer than one night, for example, the work computer is not blocked, but you can render the rest the next night. If this would work in Vray, possibly also connected with Chaos cloud, then that would be ablest awesome! I used it years ago with Iray and it saved a lot of trouble.

[SonyBoy]

If you happen to be rendering with Deadline, so far as I recall from a job I was in three years ago there are capabilities to use DR and tile rendering in the Maya submission plugin.