Hi everyone!
This is the first time im post in this forum ^^. Now im teach my self in houdini by some tutorials. And with this tuttorial: “HOU102: Introduction to Houdini 12 by John Moncrief”, i have to creat a field of grass, the base of grass is a curve and i've add a copy node to creat a filed, that's so easy but the question is: How can i modidy the grass to big in bottom and small in top and how to add a gradient color for them? Tks for read and sorry for my English!

I've not seen the tutorial in question… does it use the width attribute to set the spline thickness in mantra? If so, you can drive it with a Ramp parameter to set the grass blade profile over it's U distance.

Ari Danesh covers this nicely in another grass tutorial in the official Next Steps tut series:

http://www.sidefx.com/index.php?option=com_content&task=view&id=2488&Itemid=383 [sidefx.com]

That's great! Thanks AdamT for helps, that tutorial do not use with attrib, it's simple is a curve and when render in mantra, the grass in rectangle shape. The Ari Danesh's Tutorial so cool, and you too ^^!
Thanks and Best Regards!