Suppose you are working on a project like this William and Mary-style cradle modeled on one from the late 17th Century. How do you determine the width of the slats on the arched top of the hood? You might just use your calibrated good eye and get it pretty close. If you know the angle of the arc, you could do some ciphering and figure it out. Or maybe use some trial and error to get slats of equal width.

If you were modeling it in SketchUp, it would be a simple matter to sort them. In this video I showed one method that leverages the way SketchUp uses straight line segments to approximate curves.

This was done almost entirely with native tool. I did use the Point at Center tool to identify the center of and arc. This comes from Ruby Script Examples which can be found in the Extension Warehouse. In SketchUp 2016, the built-in inferencing would do the job and Point at Center wouldn’t be needed.

–Dave