The shift tool creates a rigid relationship between two points. It tells Visual TrueType to maintain the same relative distance between the parent and child points even if hinting has moved the parent point.
A shift differs from a link in several ways. A shift doesn’t use control values, so you can’t alter multiple shifts by changing a single ‘cvt’ value. In addition, because the position of the child point depends on what happens to the parent point, you don’t have to apply rounding to the child point, and a shift doesn’t have to move the child in full pixels. In addition, a shift doesn’t default to the one-pixel minimum used by a link.
Shifts are appropriate when:
1. The distance being controlled has no ‘cvt’ entry and doesn’t need one because the two points have a unique relationship.
2. The distance is very small and will become full pixels only at large ppem sizes.
Creating, changing, and deleting a shift works in much the same way as does a link. The main difference is that a shift doesn’t refer to ‘cvt’ values so you don’t have to apply a ‘cvt’ category and value or set a minimum distance. Like a link, a shift goes in one direction, so the toolbar has two shift tools: one for the X direction and one for the Y direction:
The respective tool will be available only if Show X Direction or Show Y Direction is selected on the Display Options dialog available on the Display menu). Similarly, Visual TrueType displays shifts only for the selected direction(s).
Selecting a shift tool changes the cursor into a horizontal or vertical arrow for the X or Y direction:
To create the shift, you drag from one point to another. Even if the first point is controlled to a grid boundary, the second is not rounded to a grid boundary (at least not by default).
Because the relationship is rigid, the shift forms a solid line with a short line at the parent point and an arrowhead at the child point. The arrowhead is parallel the X or Y direction of the shift. Horizontal and vertical shifts will be straight, but diagonal shifts will curve.
Tip When you’re not working with shifts, you can hide them to make more room on the screen for other visual hinting. In the Display Options dialog, you can set the Shifts option to show or hide Shift commands.
To create Shift commands via the keyboard, you must type the appropriate VTT Talk commands into the VTT Talk window (Ctrl + 5).
To select the XShift tool
1. In the Visual TrueType Options submenu of the Display menu, ensure that the Show X Direction option is enabled.
2. Select the XShift tool by clicking its icon in the toolbar or by pressing the F6 key.
To select the YShift tool
1. In the Visual TrueType Options submenu of the Display menu, ensure that the Show Y Direction option is enabled.
2. Select the YShift tool by clicking its icon in the toolbar, or by pressing the F2 key.
To create a shift
1. Select the XShift or YShift tool by clicking the appropriate icon, or by pressing the F6 or F2 key, respectively.
2. If necessary, zoom in for a better view. (For details, see “Resizing the View”).
3. Point on what you want as the “parent” point. Visual TrueType will display an arrow to indicate the start of the link.
4. Drag to the “child” point.
To change the “parent” or “child” control point
1. Select the XShift or YShift tool by clicking the appropriate icon, or by pressing the F6 or F2 key, respectively.
2. Point on the tail (parent) or head (child) of the arrow.
3. Drag to another control point.
To display or hide existing shifts
1. In the Visual TrueType Options submenu of the Display menu, select the Shifts option.
To delete a shift
1. Select the XShift or YShift tool by clicking the appropriate icon, or by pressing the F6 or F2 key, respectively.
2. Point on the arrowhead of the shift you want to delete.
3. Drag the arrowhead off the “child” control point, and release the mouse button. Visual TrueType will delete the link.