Xgen - Interactive Grooming

[martinmichl]

Hello

I created this logo with grass using Xgen interactive grooming

vimeo.com/219071675

pwd: gr4ssX!

(please don't spread its a client project)

Rendered with Vray

First of all I have to send out a great applause to Autodesk and the Xgen Team

The interactive grooming works like a charm and it was pure fun working on it

The grooming is done in 3hours, so all the limitations are based on the short time I put in it.

To improve the realism of the grass I think two things would be needed:

- blade shaped 

unclicking the "face camera" box only affects the preview but not the rendering

perhaps there is another way to make the tubes become flat

- wind dynamics

I faked the wind by animating different sculpt layers

is there a better way to affect the Xgen interactive

the normal Xgen had a wind function, but I don't see it in interactive

thnx in advance

Martin

[Michael_Todd · Accepted solution]

First off, very cool. Thanks for sharing..

To improve the realism of the grass I think two things would be needed:

- blade shaped 

unclicking the "face camera" box only affects the preview but not the rendering

The face camera toggle is a view port option, it does not affect rendering as having the spines always face camera is a way to prevent the flat nature of the splines from having them create areas where the hairs can be seen "Edge On". We could look into making this option apply to renders as well.

perhaps there is another way to make the tubes become flat

Are you using Arnold to render? Arnold has two render modes for splines, Ribbon (Flat) and Thick (Tube) 

Mental Ray has a Tube Shade option, I believe, but defaults to a ribbon type mode

- wind dynamics

I faked the wind by animating different sculpt layers

is there a better way to affect the Xgen interactive

the normal Xgen had a wind function, but I don't see it in interactive

We don't have a wind modifier yet (basically a moving noise field) but we plan to add one. RIght now though, you can add an animated noise texture to the Noise modifiers mask attribute and key the time setting 

You can also add a linear wire modifier and make guides for it and make them dynamic. The nHair system can then be affected by Maya fields and be blown by wind and affected by gravity.

Cheers

[martinmichl]

Hello Michael 

first of all thank for your fast and detailed answer

Makes sense that this option has to be supported by the render engine.

We are using Vray, so I have to look into it or ask in their forum if the option is available.

I will post my result when we found out.

Your wind example with the dynamic guides looks great

I will test it out

Thnx

Martin

[martinmichl]

I suppose it is not possible to use the Interactive Groom with Custom Geometry,

so to use modelled grass blades?

*m

[Michael_Todd]

No, the new system is purely for generating hair type splines. It doesn't do geometry instancing, but core XGen does, obviously.