Rotate UV of Ramp texture

[racoonart]

There's one thing I still haven't been able to figure out... I want to use a gradient/ramp in my environment (or dome light) that goes from top to bottom. That's an easy thing to do in max (see the screenshot below) but I can't seem to find a way to do it in Houdini. Any idea what I'm doing wrong or how to do it properly?

Thanks for any help

[chakarov]

Hello racoonart , this is not a perfect solution, but it works for your case.
V-Ray GradientRamp type should be "Position". V-Ray Environment should be connected to a V-Ray UVWGenToTex node /this will convert generated uvs in vector/, than with V-Ray ColorChannel you could extract only Green Channel /which correspond to v value of the uv / and connect it into gradient_position of the GradientRamp.
like this:

[racoonart]

A clever and simple solution! Thank you very much .
It's a bit more of a "hack" than I would have expected for a thing like this though (I do that all the time) - and it wouldn't work in all cases I could come up with, only really works for 90°. Maybe worth a future improvement?

[bdancer]

> It's a bit more of a "hack"

Of course it's a hack, I'll fix rotation asap.

[chakarov]

Hello racoonart , texture rotation parameter is now available in V-Ray UV Environment.

[racoonart]

Fantastic! You guys really are fast, working through those reports. Great work

[racoonart]

This, however, seems to have broken the "default" VrayImageFile environment UVs. If I use a vray image node and reference it in a dome light via op: I need to set Horizontal rotation to 180 and vertical rotation to 90 to get the same render as before (or as the dome light renders the hdri when loaded directly). See the images below for reference.

[bdancer]

racoonart, I'll restore default, sry for that.

[racoonart]

Btw, just for completeness, I think this also applies for the UVWGenEnvironment node. I have to do the same in that one to get the gradient the way I want it

[bdancer]

Yes, both nodes are sharing the same code...

[Hannes Drossel]

Hi!
Just realized this was changed. In my case I used the Horizontal rotation to rotate the dome around the world Z axis in the older version. Now (Build number:6275 hash:c636f2f) it seems like its the vertical rotation parameter I should use in this case.
Is this the correct behavior?

[Hannes Drossel]

Also, in Maya the Horizontal rotation is used to rotate the texture along the Y Axis (Up).
Make sense to me they should be the same.

Cheers!

[chakarov]

Hi Hannes Drossel , I've reproduced this behavior and reported it as HOU-1846 and will write back here one it is fixed. Thanks for the feedback.

[Muhammed_Hamed]

Hi
Is this an intended new behavoir for horizontal/vertical rotation now?
All my scenes use horizontal rotation to rotate an HDRI, this doesn't work anymore, I need to set horizontal rotation to Zero and use vertical rotation instead.
Just making sure before changing my scenes.

[Gosho.Genchev]

Hey, Muhammed_Hamed ,

no, that is not intended. Could you please try with the latest nightly build ? This behavior should be fixed now.

Best regards!