Is there any way to use FME Desktop to square (true) polygon corners to 45 or 90 degrees?

I was wondering this as well. Does anyone know how it is done?

Maybe something like this:

1. Create the 2D Oriented Bounding Box of the feature (BoundingBoxReplacer)
2. Calculate the azimuth of one side of this Bounding Box
3. Convert the original polygon to segments of 2 points (Chopper)
4. Calculate the azimuth of every segment
5. If the azimuth of a segment is close enough to the azimuth of the bounding box (or close enough to this azimuth +/- 90 or 180 degrees, or - if you want to - close enough to this azimuth +/- 45 degrees or +/- 135 degrees), rotate the segment around it's middle point to the desired azimuth
6. Calculate the intersection point of every pair of adjacent segments
7. Re-create the polygon from the intersection points

Ensure the polygons have no corners of (approximately) 180 degrees.

Make sure every original polygon has a unique ID, and use Group By on this ID where this applies.

An implementation of the process mentioned above (not thoroughly tested!):

The workspace uses a simplified version of the HorizontalAngleCalculator from FME Hub.

Somebody asked me for the workspace, so I re-upload it here.

However in retrospect I think the workspace is much more complicated than it needs to be.

A lot of the initial work can be done by the PolylineAnalyzer (FME Hub).