We use shape extraction as a process step to fit projects to existing shapes. The process involves taking a photo of an item for which a custom fit is required, with a reference item. The photo is then imported into the the tool used in the next design step, e.g. Inkscape or Fusion 360. In that tool, a shape is created that is the size of the reference item, and then the image is scaled so the reference item and the reference shape match. This allows us to create custom items with an accurate fit.
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