When you create a link, Visual TrueType assumes it will refer to a ‘cvt’ value. Before Visual TrueType can select the best ‘cvt’ value for the link, you must provide more information. Visual TrueType knows that the link should refer to a ‘cvt’ value for a stroke. However, you must specify:
· Which category of stroke to use: straight, round, or other.
· The minimum distance Visual TrueType should maintain between the parent and child points in the link.
While using either link tool, you can display a menu of options for the arrowheads on links. Your choice specifies both a control value category and the minimum distance between the parent and child points. Otherwise, you can change the link to a distance by telling Visual TrueType that the link does not require a ‘cvt’ value.
Visual TrueType displays different menus, depending on the direction of the link:
Control-value category and minimum distance options for the X and Y directions
The first row of each menu offers the same four choices (shown below for the X direction only):
Option |
What It Means |
|
The link becomes a distance without a ‘cvt’ value because it doesn’t relate to any other character in the font. When Cvts is selected on the Visual TrueType menu, the link will not display a highway sign. |
|
The link refers to a control value for a non-specific distance, such as serif lengths. Use this category for strokes that are neither straight nor rounded. |
|
The link refers to a control value that indicates the dominant width of a straight strokes (the arrowhead is straight, not pointed). |
|
The link refers to a control value that indicates the dominant width of a round stroke (the arrowhead is round, not pointed). |
The arrowheads shown on the links and distances correspond to your menu choices:
The X links of a Times New Roman “B” with arrowheads denoting ‘cvt’ categories.
This first row of link options instructs the rasterizer to maintain a minimum distance of one pixel for all thin black distances (but not white or gray distances) that are entirely “inside” the glyph. However, you may want to override this with choices from the second or third rows.
For example, depending on the rounding method, both parent and child point are typically rounded to (the nearest) grid line. As a result, Visual TrueType rounds the distance between the parent and the child point (in the X or Y direction) to the whole pixel. This number may be 0 for small ppem sizes and short links, so a fairly thin stroke might vanish. You can override this result by choosing from the second row to maintain the minimum distance.
The choices in the second row look like they repeat the choices of the first row, but they feature an extra symbol that looks like the “open the door” button in elevators:
Each choice here tells the computer to maintain a minimum distance when the computer normally would not. In the example linking the Times New Roman “m” earlier in this chapter, links restored the serifs, even though the distance across them was less than half a pixel. The first option in the second row creates a distance (no ‘cvt’ value) that maintains a minimum distance of one pixel:
Conversely, if Visual TrueType applies the minimum distance when you’d rather it didn’t, you can select options from the third row. These permit “closing” the distance to 0 pixels. The third row has an extra symbol that looks like the “close the door” button in elevators:
Keeping track of overrides is important. Visual TrueType can display the “elevator door” symbols next to any highway sign with an override.
By default, the minimum distance is 1 pixel. However, you can use any elevator door symbol to change the minimum to any distance between 0 and 8 pixels (in increments of 1/8 pixel). For example, increasing the minimum distance to 2 pixels might make a bold font look darker than the “normal” font with the default minimum distance of 1 pixel.
Note By default, Visual TrueType applies the last-selected option for ‘cvt’ category and minimum distance to each new link you create. To take advantage of this default behavior, create all links that use the same category and distance, then select another arrowhead from the pop-up menu, create all those links, and so on.
To choose a control value category and minimum distance for a link
1. Select the XLink or YLink tool by clicking the appropriate icon, or by pressing the F5 or F1 key, respectively.
2. Point to the arrowhead (not the child point) of the link.
3. Hold down the right mouse button, and select in the menu.
To display override options on links
1. In the Visual TrueType Options submenu of the Display menu, select the Minimum Distances option.
OR
1. Click Options on the Display menu.
2. Set the the Minimum Distances option.
3. Click OK.
To change the minimum distance for a link
1. In the Visual TrueType Options submenu of the Display menu, ensure that the Minimum Distances option is enabled.
2. Point to the elevator sign of the link where you want to change the minimum distance.
3. Hold down the right mouse button.
4.
In the ruler, drag until the black bar reaches the distance you want.
When the pointer goes beyond the left or right edge, the ruler will start
scrolling. The further you drag, the faster the scrolling.