Segments and Curve Types

You can edit the path between nodes directly. A segment can be reshaped, moved with its endpoints, or converted to another representation. Decide whether you want to change its shape or only its position before beginning the gesture.

Non-Node Editing

With the Contour tool, point directly at an unselected curve between its nodes and drag. This non-node editing reshapes the segment by moving its controls. It is useful when you can see where the edge should go but do not want to position each handle separately.

A short drag uses adaptive precision; longer travel gradually approaches ordinary pointer movement. Adjust the non-node editing factor under Preferences > Distances if the response is too slow or too direct.

Preferences > Editing > Curve drag keeps handle direction controls whether handles retain their directions during a segment drag. With it on, handle directions stay fixed. With it off, directions can change, and neighboring segments connected through smooth nodes may be affected. Inspect the neighboring joins as well as the segment under the pointer.

Move instead of reshape

Dragging an unselected straight segment near its center moves both endpoints. Near an end, the gesture can move that endpoint instead. Dragging an unselected curve normally reshapes it.

To translate a curved section, select the segment or its endpoint nodes first, then move the selected section. Check that the adjoining handles needed for the move are included. A partial-path move can still alter the segments connecting the selection to the rest of the contour.

For deletion, Backspace removes the selected section and reconnects the remaining path. Forward Delete removes it with an opening. On a compact Mac keyboard these are Delete and Fn+Delete, respectively. Inspect the resulting endpoints or replacement curve immediately.

Enable Curve tension in the measurement displays, or use its Measurements-widget button, when you want numerical feedback on handle extension. A tension readout describes the current geometry; it does not impose a quality standard.

Tunni Lines

A Tunni line connects the two off-curve handles of one cubic segment. Those handles belong to different endpoint nodes; it is not the line connecting the incoming and outgoing handles of a single smooth node.

Press L in the editing context, or enable Tunni Lines in the View controls. Move the pointer between a curve's handles to reveal the blue dotted line and its control point.

Drag the line to adjust both handles' tension together. Drag the Tunni control point to change the balance between the handles as well as the tension. Shift-drag the point for a more symmetric adjustment; Option/Alt-drag the line for asymmetric control. Watch the actual curve while moving the control: the dotted line is an editing aid, not part of the outline.

Click a Tunni line to activate it. Use Shift-click to add others when you want a common adjustment across several segments. Contour > Edit Tunni Lines activates eligible Tunni controls from the current segment or point selection; the Node panel offers another access point. Inspect which controls become active before moving them together.

With a Tunni control active, arrow keys provide incremental adjustments. Up/Down changes tension; Option/Alt with the arrows provides additional directional and balance adjustments. The effect depends on the segment's orientation, so read the curve and tension values instead of assuming that an arrow means an absolute canvas direction. Press Esc to leave Tunni editing.

Double-click actions can balance or harmonize curves. Those quality operations are covered in Harmonizing Curves and Smart Nodes; use them deliberately rather than as a way to select a line.

Converting between Lines and Curves

Select the segment's endpoints and choose Contour > Convert > To Curve to give a straight section curve controls. Handles are placed one-third of the segment length from each endpoint, aligned with the original straight direction, so the segment may still look straight until you reshape it.

The selected segment’s context menu provides another route to To Curve.

Choose Contour > Convert > To Line to replace the selected curve section with a straight connection. This discards its curvature. Check the adjoining node relationships after conversion.

For direct single-segment conversion, first turn off Preferences > Editing > Select segment on outline click. Then Option/Alt-click a line; add Shift to create a smooth curve transition at its ends. With the preference on, the gesture can select instead. Use the menu route if you want to keep that selection behavior.

Deleting a curve handle can also reduce its segment to a line. Retracting a handle, converting the segment, and changing a node's smooth property are different operations; choose the one that expresses the intended structural change.

Conversion separates the segment's representation from the shape you see. A line converted to a curve may initially look unchanged because its handles are aligned along the original segment. The new controls make later bending possible; conversion alone need not introduce a visible bend. Move the controls only after checking that the intended segment was converted.

The reverse operation is a geometric simplification. A curve can bow away from the straight connection between its endpoints; To Line removes that curvature. Compare the resulting edge with the surrounding silhouette, especially when the original segment was short or nearly straight. A small difference at high zoom can still matter to a smooth join or a narrow counter.

Before converting several segments, inspect the selection. A mixed group can include intentional straight edges and curves whose shape you meant to retain. Applying the same operation to all of them is a design decision, not merely a way to make their control markers look alike. Afterward, check the filled result as well as the point structure. Undo if the selection was broader than intended.

Balance operations are developed in Harmonizing Curves and Smart Nodes. Converting drawing content to a component or an element changes a different level of structure; those workflows are taught in Building Composites by Hand and Element References.

Converting Curve Types

As introduced in Curves, Direction, and Fill, a PS segment uses cubic controls and a TT segment quadratic controls. FontLab permits mixed PS and TT segments during development. Conversion changes that representation and can change the number of points. Preserve the source before a major conversion.

With Select segment on outline click off, Option/Alt-click a PS curve to open Convert to TT. Try the choices for one, two, or three off-curve points, or Auto, and inspect the live preview. Confirm with OK or Return/Enter; use Revert to abandon the conversion. Shift+Option/Alt-click performs the automatic conversion without the dialog.

Option/Alt-click a TT curve converts it to PS. For larger scopes, select the intended contours and use Contour > Convert > To PS Curves or To TT Curves. These menu commands can affect a whole contour even when only part is selected; use the direct gesture when a single segment is the required scope. With no selection, the current drawing is the target.

Quadratic geometry can be represented exactly as cubic geometry, though simplification and rounding can still change the result. General cubic geometry needs approximation when converted to quadratics. The conversion settings under Preferences > Operations control the accuracy and point-count tradeoff.

After conversion, inspect at high zoom and compare the filled result at text size. Export can perform the geometry conversion required by the target format, but inspecting it during development makes any loss of shape easier to find. Export choices are covered in The Export Process.

Judge a conversion by geometry and usable structure together. A tighter approximation can preserve the original curve more closely while adding points. A simpler result can be easier to edit but depart farther from the original shape. Neither a lower point count nor a successful conversion dialog proves that the result is appropriate for the design.

Compare the converted section with its neighbors, not only with its own previous outline. Check for visible changes near joins, at extrema, and around narrow spaces. Then examine it at the size at which the font will be used. High magnification reveals geometric differences; a text-size view shows how those differences affect the visible result.

Keep the editable original until the converted version has passed that comparison. Repeatedly converting between representations can add approximation or rounding changes without improving the design. Choose the target representation deliberately, inspect the result, and continue editing from a known version rather than treating conversion as a reversible display switch.