# Rounded Rectangle Cross-Section Basics

## Introduction

The Rounded Rectangle cross-section applies a rectangular section of set width and height and fillets the corners with a set radius. Additional parameters control this shape such as Keystone and Skew. Keystone will change the relative length of the top and bottom sides to make a trapezoidal or triangular shape. Skew will shift the top and bottom sides in opposite directions to make a rhomboidal profile. Vertical Skew behaves similarly for the left and right sides. Key Corner is an important feature that will force the interpolated W lines about the body to pass through the cross-section corners, ensuring a purely sharp edge if desired.  Note that the Width and Height are the horizontal and vertical distances, respectively, between the side midpoints and are not the physical dimensions of your cross-section resulting from keystone or skew.