Issue with Xgen and Custom Shader Parameter

[alessandromastronardi]

Hello, I'm using Maya 2017 and having troubles to assign a painted map or texture to a Xgen description. Length map ptex do work as expected, while color maps seem to be ignored by the Vray renderer. I'm a Maya/Vray newbie so I expect I'm doing something wrong. Followed also the guide here (https://docs.chaosgroup.com/display/...A/XGen+General) with no luck. As a note, I've set a default project path (Xgen expects to work that way it seems).testPtex.zip
I attached the project I'm working on, anybody can weigh in and maybe see if is able to create and assign a color map to it? Thanks.

Project files: testPtex.zip

[yolov]

What attribute you'll like to map? I read through our xgen tutorial to make sure it still holds for 2017 and it does. When you create a map for an xgen attribute you can do one of two things - paint a ptex map or load a bitmap (if you manage to locate the file correct file node in your scene - the proper way to do that still eludes me). If you do either one of those things, you should click the "save" icon for that attribute so xgen knows to refresh your changes. Does this help?

[alessandromastronardi]

What attribute you'll like to map? I read through our xgen tutorial to make sure it still holds for 2017 and it does. When you create a map for an xgen attribute you can do one of two things - paint a ptex map or load a bitmap (if you manage to locate the file correct file node in your scene - the proper way to do that still eludes me). If you do either one of those things, you should click the "save" icon for that attribute so xgen knows to refresh your changes. Does this help?

Hi Alex thanks for the prompt response. Yes it was helpful but I had to run lot of trial and error until I sorted out the correct procedure. Here it is what worked for me, in case somebody else comes up with the same question:

- first of all, assign a Lambert shader to the surface that will hold the Xgen collection; VRay shaders are not paintable from what I understand
- create the Xgen collection and assign a VRayMtl to the description, coupled with a VrayHairSampler attached to it
- create a root_color and tip_color maps in the Custom Shader Parameters; root_color and tip_color seem to be mandatory names, if I try to use other names the painted maps won't be saved or applied to the Xgen description
- at this point the painted maps should be working and ptex set on hairs; eventually one can go in the Node Editor and change the texture maps (generated from the 3D paint) with custom ones. In this case, root_color and tip_color definitions must be resaved in the Custom Shader Parameters so that Ptex data will be updated.