Vray Triplanar axis rotation problem

[felix_schwarz]

Hello,

I have been using triplanar for a while now, but I do not know if Chaos Group changed something with the recent vray updates or I am just dumb, but when I try to plug a texture to my projection axis, the x-axis makes a 90 degree rotation on my texture (image 1). Wehn I try to rotate the texture back using the "Texture Rotation" attribute, it works for one side of my object, but the other side is upside down (image 2). Is there something I am not seeing, or is there a solution? By the way, the object has 0 on all transformations.

[hermit.crab]

If I understood correctly, this happens because the texture rotation parameter affects the projected textures around their respective projection axis (check docs). If I'm mistaken, please clarify.

[felix_schwarz]

so do I understand it right, that it is different on both sides, like the back rotates +90° and the front -90°? How am I than able to get it to rotate in the same direction on both sides?
Why is it even rotated at all? Like when I use triplanar mapping with a V-ramp (horizontal lines), they appear horizontal on the z-axis, but vertical on the x-axis?
Is it even possible to get horizontal lines around a cylinder with triplanar mapping?

[damaggio]

Hi Felix, I understand your frustration, I never quite understood why you need to rotate one axis for this to work.I use Triplanar quite often and need to save these little tutorials to help me remember.
Also keep in mind that the 2dtexture placement node does not work in the viewport , only the triplanar settings are visible, to see the changes in the 2D texture you need to be in IPR mode.

On a side note, I noticed you don't have your swatches enabled , you can have textures and shaders all the way to 12K in preferences.

[felix_schwarz]

Thanks damaggio for you response. I know that the textures can be rotated, but I'm still not able to get it right on ALL sides. it either is pointing in the ricght direction on the +x OR -x side. See attached images. Is it possible to rotate +x different than -x?

[felix_schwarz]

you can see it better with this beautiful colorpalette... the texture is correct on 3 sides, but not on 4...

[damaggio]

yeah I see what u mean.....I'm testing it (I generally don't use triplanar on cylinders)

[felix_schwarz]

thanks mate, really appreciate your help. The cylinder is only for testing. I wanted to use vraytriplanar to create an oxidated metal tools with this rainbow colors on the metal. Something like in the image. And it would be awesome to combine UVs for surface details and triplanar for the color effect... thats where i stumbled upon the problem. I'm aware that I could do it with textures as well, of course, just am curious if this really isn't possible =)

[damaggio]

Ummm....I got it to work...I think, by using Reference Transform option X -90 and the texture points up all around the cylinder.

[damaggio]

The metal would be just easier with normal texturing workflow....but the triplanar I wanted to figure it out.

[damaggio]

I hope that's what you need, I gotta get back to work but I'll keep watching your post. I learned something new though....Good luck.

[felix_schwarz]

damn, you're a genius! thanks so much... I really thought I tested this as well... even created a locator and connected world matrix since I found something about this somewhere. Anyway, it works now, thank you very much for your help, really appreciate it! Have a great day

[damaggio]

Great....but for Chaos, I still wonder WHY one axis has to be rotated for it to work in either Local or Reference Transform.

[hermit.crab]

It's because of the Y-up coordinate system in Maya. The VRay Triplanar is Z-up default, which means switching to Y-up "rotates" the textures (check graphs). Arnold works in a similar matter, but it is Y-up default. Both engines exhibit similar results when compared in their natively designed coordinate system.
Maybe it's a good idea to implement some kind of an adaptive texture rotation based on the coordinate system, so that the triplanar results with Y-up and Z-up are the same.

[damaggio]

Gosh, I would not have guessed this in a million years, thanks for finally clarifying this for all of us. This is not an issue for me anymore but I think if there’s a way to adjust this for the future generations of Vray users so they don’t have to scratch their heads about this it would be very welcome. Thank you Hermit.