Making a pattern on a surface that transforms from one shape to another

I am trying to create a pattern on a surface face that has shape transitions. For example the pattern has a rectangle that transitions into a circle. I have been able to figure out how to create a pattern of an individual object that transform’s in size.

(13.8 KB)
Rhino Chair.3dm (2.6 MB)

Any suggestions or direction to a tutorial would be appreciated.

This is how I did this: Divide the rectangular curve end the circular curve into equal points. Draw a line between these points (you may have to use shift to get the corresponding points). Divide the lines into points. Connect the dots.
(See example on my site. There I used Vectorworks/Marionette, but Rhino/Grasshopper is probably easier.)

You can also make a loft of the rectangle and the circle and use contour to get the shapes