Overlaps and Boolean Operations
Overlapping strokes are convenient construction pieces. Contour operations can combine them into a new boundary or use one shape to cut another. These commands rebuild geometry: the original internal edges and point structure may be lost.
Keep an editable source before consolidating a drawing. For interpolation sources, retain compatible construction rather than independently rebuilding every master.
Removing and Making Overlaps
Remove overlap
Use Contour > Remove Overlap to resolve overlapping regions into the resulting filled outline. For example, two overlapping rectangles forming a cross can become one outer boundary around the cross. The buried edges disappear.
Do not independently remove overlaps in masters that must interpolate. The resulting point counts and contour structure can differ between masters even when their visible shapes remain similar. Preserve the construction source and perform final overlap processing on static output or through a suitable export workflow. If you intentionally restructure interpolation sources, re-establish and check compatibility afterward; see Interpolation and Compatibility and Previewing, Diagnosing, and Fixing Interpolation.
Selecting any part of a contour can bring that whole contour into the operation. An isolated inner contour can also behave differently from that same contour processed together with its outer boundary. Include the intended fill context rather than treating selection as a rectangular clipping area.
Scope matters when the glyph contains several elements, the containers for drawing content. With Edit Across Elements enabled (see Element Transformations), Remove Overlap can combine content from participating elements before resolving it; this can include more contours than the visibly selected nodes alone suggest. Turn that option off and work in the intended current drawing for a narrowly scoped operation.
From the Font window, Contour > Remove Overlap first flattens the layer’s participating content before resolving its overlaps. This can change the element construction as well as the contours. Use the Glyph-window selection workflow below when you need to control a narrower drawing scope.
- Make the intended glyph and drawing content current.
- Select the contours to process, or clear the selection deliberately for the broader operation.
- Choose Contour > Remove Overlap.
- Inspect the filled silhouette, counters, and nodes around every former intersection.
The command removes filled inner loops and unfilled looped corners and can resolve certain degenerate paths. Nodes uninvolved in the overlap are preserved; this is not an implicit general Clean Up pass. It is not a general guarantee that every curve has been simplified or that all quality issues are repaired. Inspect small counters and self-intersections in particular.
Make an overlap
Contour > Overlap > Make Overlap creates construction overlap from an existing junction. Select two suitable corner nodes for a simple split, or four suitable corners for a crossing overlap. The command separates and extends the parts and closes the resulting paths.
It is not a history-based reversal of Remove Overlap: it constructs an overlap from the current geometry and selection. It cannot reconstruct every original piece automatically. For a split involving smooth-node junctions, the Scissors tool provides an interactive route.
After making the overlap, inspect both the paths and the fill before moving the parts independently. A useful overlap should preserve the intended visible shape while giving you a more convenient construction.
Boolean Operations: Subtract, Intersect, Exclude
These are the Boolean or pathfinder operations familiar from vector-drawing applications: Subtract is a difference, Intersect retains the common area, and Exclude removes the common area from the union. The Contour > Overlap commands work with front and back operands formed from closed contours in the current contour-bearing element. The selection determines those roles:
- Selected closed contours form the front operand.
- Unselected closed contours form the back operand.
- With no closed contour selected, the last closed contour becomes the front and the remaining closed contours form the back.
A partial point selection still identifies an entire contour. Select the cutter explicitly instead of relying on drawing order. Selecting every closed contour can leave no back operand, so the operation has nothing to combine it with.
| Command | Retained area |
|---|---|
| Subtract | The back minus the area covered by the front |
| Intersect | Only the area shared by front and back |
| Exclude | The combined area with their common region removed |
Unselected closed contours in the same element participate as the back operand; leaving them unselected does not protect them. Protect unrelated contours before running the operation; the methods below explain how.
Cut one shape from another
For a simple subtraction, draw two overlapping closed contours in the same current drawing, select the intended cutter, and choose Contour > Overlap > Subtract. The cutter is consumed by the operation. Check that the retained shape is the intended back operand; undo and change the selection if the result is reversed.
Intersect and Exclude use the same operand setup. Intersect can leave an empty result when the shapes do not overlap. Exclude creates the non-shared regions rather than merely deleting whichever contour is selected. The intersection boundary is wound in the opposite direction so it forms a counter; recall contour direction and fill in Curves, Direction, and Fill. Consistent winding also matters when removing overlaps.
Protect other contours
Open contours are excluded from these Boolean operations. For an ordinary closed path you need to protect temporarily, break it at a known node, perform the operation, then select its coincident endpoints and join them again. Check that it is closed afterward.
Keeping unrelated content in a separate element is another way to establish a clear operation boundary; see Element References. If content remains unchanged unexpectedly, also check whether the two intended operands actually belong to different elements.
These commands commit the new geometry. The Fill tool and Fusion filter can retain the original construction for later adjustment; see Boolean Assembly: Fusion, Clipping, and the Fill Tool. For a committed Boolean result, inspect closure, direction, point count, and the exported silhouette before considering the operation complete.