Rather than bending the grass uniformly in one direction, we can use expressions to bend the grass in random directions. Bend U and V control how much the spline is bent at the corresponding CV. 0 is no bend, and 1.0 is a 90-degree bend.
• Click on the Expression icon (see below) next to Bend U[0] and Bend V[0] and enter the following text in the XGen Expression Editor: