UV Pass?

[tehfailsafe]

Is there a way to export a single mesh uv pass within vray? I haven't tried to do this before, so I have no idea.

The only way I have come across is by using the Gbuffer uv pass, but it is for all the objects. I could isolate the object I want, but it would mean two renders rather than one. Not a big deal but if vray can output a vrayuvtex or somethign that I'm just not seeing that would be great!

[joconnell]

Depending on what you're feeding it into as a compositor you could also use a multimatte element and assign an object id for just the object you want to generate an alpha for it or assign an extratex element to just that object with a white vray color map too.

[tehfailsafe]

The client is looking to use the re:vision plugin in after effects to do the compositing, basically it's just a screen replacement of a laptop so they can change it after the render anytime they need to.

http://www.revisionfx.com/products/remap/

[joconnell]

Getcha. I'd render out a custom alpha for the object and your uv pass with your main render. They can use the set channels or set matte filter in after effects to assign your custom matte as an alpha for the uv pass and you'll get your single uv part. They may need to do this as a separate comp in afx and then use the comp inside their main comp for after effects to recognise the uv channel with the matte swapped in. It's a bit funny about the order that it processes things in and sometimes won't pick up that you've swapped mattes around for a layer so you need to do this in a separate comp to get afx to then treat it as a dumb piece of footage.

[tehfailsafe]

Interesting.
I'll try that.

The problem I've been running into with exporting the uv pass is that i have to turn off the vray frame buffer and export as .exr, then go into config of the exr to save out the uv pass. Not a big deal but when I go into AE to extract it I only have 2 channels for uv, but it requires RGBA. So I put U to R and V to G, but then the B channel has only the "true" RGB blue channel data, which makes the red/green mixture look pastel with the details of the original texture on it as well. This confuses the crap out of the plugin.

I'm not a compositor, but I do want to make sure the pass I send over will work for their needs before I ship it, so I'm mostly just testing to confirm.

[joconnell]

I getcha. Would the Vraysampleinfo render element set to uv mode work?

[Dave_Wortley]

You can also save as RLA/RPF to have UV information.

[duke2]

Yeah I thought the VraySampleInfo element provided this as well.

[tehfailsafe]

thanks! That worked perfectly!