Boolean Commands

Boolean operations let you build complex shapes from simpler ones by controlling how overlapping polygons interact. Whether you're merging sites, finding shared areas, or cutting one shape out of another, these tools give you fine-grained control over your geometry.

Boolean operations in Giraffe work on enclosed polygons (not lines or points).

Useful when you need a flexible, interactive approach to combining or removing overlapping areas — rather than committing to a specific operation upfront, you can pick exactly which intersecting regions to keep or discard.

The Boolean tool allows you to select which parts of overlapping enclosed polygons to keep or remove. It is basically Union, Intersection, and Difference in one command.

Select the polygons

Select Boolean from More Tools/Command Line.

Click on the intersecting areas you want to keep. They turn Green.

Click again to remove them from the set. They turn red.

Click proceed to keep the changes.

Create a new polygon that represents the merged geometry of 2 or more enclosed polygons. Useful when two or more adjacent or overlapping sites need to be merged into a single polygon — for example, consolidating parcels under common ownership.

Select the polygons

Select Union from More Tools/Command Line.

Create a new polygon from the intersection of 2 or more enclosed polygons. Useful when you need to isolate the area shared by two or more polygons — for example, finding the overlap between a site boundary and a zone.

Select the polygons

Select Intersection from More Tools/Command Line.

Cut out an area in a polygon based on an overlapping enclosed polygon. Useful when you need to cut one shape out of another — for example, creating a hole in a polygon for a courtyard or exclusion zone.

Select the shape you want to cut from

hold shift

select the shape you want to cut with

Select Difference from More Tools/Command Line.