connecting a vrayhairsamples node to a texture ramp gets rid of the ramp in the render

[Futarilus]

Hi there,

I've been using vray for a couple of days, working through the official documentation and a few tutorials I was able to find.


My issue is pretty much summarised in the title. I'm trying to bake a proper eyebrow texture, figured out how to bake the alpha map but the diffuse map looks straightup bad (which stems from my lack of knowledge with vray).
However, I followed exactly the documentation on how to apply the vrayhairsamples node (the DistanceAlongStrand specifically) to a texture ramp to a VrayHairMtl to give each hair strand the same texture gradient, but it doesn't work in the final vray baking / projection process.
I've created an eyebrow using xGen's interactive grooming tools, applied the vrayhairmtl and in the hypershade editor connected the nodes as followes: VRayHairSampler [DistanceAlongStrand] - Texture [VRamp] V channel - VRayHairMtl [Colour channel].
In the viewport, the hair takes over the texture gradient just as expected from what the node setup looks like, but in the render, it only takes the root colour and applies it across all hair strands. (In a test scene, red as root - yellow as tip: all hair was rendered red, in viewport all hair was going from a red root to a yellow tip).

I'm using the newest version of Maya 2018, Win7 64bit, and the newest version of Vray for Maya.

Thanks in advance for any feedback

All best,
Thomas

[yolov]

Could you share an example scene or a screenshot of what the shading network looks like?
With no actual info, I can only guess that you might have connected the hairSampler to the ramp's vCoord while the ramp is in Uramp mode (or the other way around). Imagine the gradient rotated by 90 degrees in this case and the hairSampler sampling all the bottom line values (being all red in this case). Basically, if the ramp is in Vramp mode, you need to connect the hairSampler to the vCoord and when in Uramp mode - in uCoord respectively. Can you check if that's the case?

[Futarilus]

Here's a screenshot, representing what I wrote about.

[yolov]

I see. The setup looks correct and I made a simple test following your description, which seemed to work for me. Can you share a scene that I can have a look at?