If you have used the Marquee Tool, you know it allows you to create cuts through your model… but the limitation of the standard Tool is those cuts will be straight edged. The options for the Marquee Geometry are shown in the InfoBox below:
As you can see, there is a Polyline, a Rectangle and a Rotated Rectangle - so how did I manage to create this…
Well, I did use a Marquee, but I ‘cheated’ slightly! To create custom shapes with curves as shown above you need to draw a Polyline on plan to show the shape you want to cut in 3D. Once this is in place, all you do is Magic Wandthe Polyline with the Marquee Tool as shown below:
I have used the Thick Marquee to cut all stories of the model - you can use the Thin Marquee to cut only the current storey if you wish.
To control the accuracy (segmentation) of the cut on the curved sections, go to Options> Magic Wand Settings…
Set the options to Linear Segments as the Tracing Method then Segments Along Arcs. The default value for this is 36 which can be a bit over the top so feel free to adjust and try different values to find what works best for your project.
To view the content of the Marquee in the 3D Window, right click the mouse and select Show Selection / Marquee in 3D or press F5 (Windows) or F4 (Mac OS).