ALIGN

ALIGN(parentA, child1 [,childn]…, parentB)

Abbreviation: AL

parentA	endpoint of line
child1	point to be aligned
childn	additional points to be aligned
parentB	endpoint of line

ALIGN unconditionally forces all points listed between pointA and pointB to align with the line defined by endpoints pointA and pointB. In the example below, the command would be ALIGN(A,1,2,3,B). This would force points 1, 2 and 3 to align with line AB.

A midpoint to be aligned is moved perpendicular to the line, except if the midpoint is at the corner of a junction, such as in an “F.” In this case, the point is moved along the axis of the intersecting line.

ASM

ASM("TrueType instructions")

Abbreviation: AS

This command allows you to embed low-level TrueType instructions within VTT Talk. This had previously been required to handle deltas and rounding states. These effects can now be controlled using the new VTT Talk commands XDelta, YDelta, XHalfGrid, YHalfGrid, XDownToGrid, YDownToGrid, XUpToGrid, YUpToGrid, XDoubleGrid, and YDoubleGrid.

Try to avoid using the ASM command since the VTT Talk compiler will not check low-level instructions contained within an ASM command. Thus, you may inappropriately change the graphic state, such as the freedom or projection vectors, without the compiler being aware of the change.

DSTROKE

DSTROKE controlflags (point1, point2, point3, point4 [,cvt])

Abbreviation: DS

controlflags	specify which points in the pairs are stationary and which are floating
point1	bottom left control point of stroke
point2	bottom right control point of stroke
point3	top left control point of stroke
point4	top right control point of stroke
cvt	width of stroke along the X axis (not perpendicular to the side of the stroke)

The DSTROKE command is used to control diagonal strokes, such as the arm or tail of a “K.” The DSTROKE command ensures that the left and right edges of the diagonal stroke are parallel, and that the “stair-step” pattern (phase) of the stroke is identical on both sides of the stroke at low ppem sizes. The ISTROKE command (not DSTROKE) is used to control italic stems.

Anchor the top right point of the stroke in y before using the DSTROKE command.

The CVT number specified indicates the width (along the x or y axis, depending on the angle) of the diagonal stroke. If a CVT number is not specified, the compiler will search for a CVT number with the following characteristics:

1. the CVT number is in the same character group as the glyph (uppercase, lowercase, etc.), and
2. the CVT comment indicates “New Diagonal” in “X” or “Any Direction.” If such a CVT value does not exist, the compiler will report an error and you will need to specify a CVT number, or create a commented CVT value that has the above characteristics.

The DSTROKE command first extrapolates the lines containing the control points and moves the pairs of control points so that they align on the same horizontal or vertical line, as below:

Move point4 and point2 to the heights of point 3 and point1, respectively

The command then controls the distance horizontally or vertically from the stationary control point to the floating control point:

Control the diag. width (full amount of pixels)

Then the floating points are repositioned at their original height, but with the new width.

Move point4 and point2 back to their previous heights

Resulting in:

FIX_DSTROKES

FIXDSTROKES( )

Abbreviation: F

Command Type: Action

This command touches any points in a diagonal stroke that may have been left untouched. This ensures that the SMOOTH command will not change the stroke weight. If all pertinent points have been touched, this command is dropped during compilation.

This command is only necessary when using the STROKE command (not the DSTROKE or ISTROKE commands). When using the STROKE command the top floating point is typically left untouched.

GRAB_HERE_IN_X

GRABHEREINX (point1, point2)

Abbreviation: G

Command Type: Informative

point1	point farthest left on the visual black body area of the glyph
point2	point farthest right on the visual black body area of the glyph

The GRABHEREINX command is created by the autohinter to calculate and control the left and right sidebearing of a glyph at small sizes. The command affects the control values associated with subsequent LINK commands, causing all sidebearing space to be combined on the right side of a glyph at low ppem sizes.

GRABHEREINX must be followed by LINK commands linking the left sidebearing to point1, and the right sidebearing to point2.

For example, the command GRABHEREINX(1,2) would have the following effect on a glyph when the sum of the sidebearing values are a pixel or less.

This command is more likely to have an effect on sans serif fonts, because serif fonts are typically designed with extra space to ensure that serifs do not run together.

HEIGHT

HEIGHT(point1, cvt1)

Abbreviation: H

Command Type: Informative

point1	point whose height is being set
cvt1	CVT number with height value

The HEIGHT command allows you to specify the height a point by associating it with a control value. HEIGHT will have no effect until an ANCHOR command is encountered.

You can also set the height of a point using only the YANCHOR command, which contains both point and height arguments.

Square cap height characters	Round cap height characters
BDEF	CGOS

INTERSECT

INTERSECT(point1, point2, point3, point4, point5)

Abbreviation: IN

Command Type: Action

point1	point to be placed at intersection of two lines
point2	endpoint of first line
point3	endpoint of first line
point4	endpoint of second line
point5	endpoint of second line

This command ensures that pointl will be placed at the intersection of the two lines described by the line from point2 to point3 and point4 to point5. Only use this command if point1 is actually located at the intersection in the original outline, otherwise the outlines will never be rendered truthfully to the original shapes.

ISTROKE

ISTROKE controlflags (point1, point2, point3, point4, cvt1, cvt2, phaseFlag [,cvt3])

Abbreviation: IS

Command Type: Action

controlflags	specify which points in the pairs are stationary and which are floating
point1	bottom left control point of stroke
point2	bottom right control point of stroke
point3	top left control point of stroke
point4	top right control point of stroke
cvt1	bottom serif height (or baseline if sans serif)
cvt2	top serif height (or cap height if sans serif)
phaseFlag	0,1,2, or 3 (see below)
cvt3	width of stroke along the X axis (not perpendicular to the side of the stroke)

Use ISTROKE to control the width and phase (stair-step pattern) of an italic stroke. ISTROKE works specifically for italic strokes that are closer to vertical than horizontal. Anchor the top right point of the stroke in y before using the ISTROKE command.

ISTROKE>>(2,9,3,8,32,29,3,61)

ISTROKE first extrapolates the upper control points to the bottom of the top serif, and extrapolates the lower control points to the top of the bottom serif. Then the floating side of the stroke is moved to be the width in X (along the X axis) as specified by cvt3.

The compiler uses the italic_run cvt to control the italic run of the glyph.

Cvt3 indicates the width (along the x axis) of the diagonal stroke. If a CVT number is not specified, the compiler will search for a CVT number with the following characteristics:

• the CVT number is in the same character group as the glyph (uppercase, lowercase, etc.), and
• the CVT comment indicates “New Diagonal” in “X” or “Any Direction.” If such a CVT value does not exist, the compiler will report an error and you will need to specify a CVT number, or create a commented CVT value that has the above characteristics.

For glyphs with a junction in the middle of the italic stem, such as a “B,” the points at the top and bottom of the middle bar need to be interpolated after the ISTROKE command so that they stay properly aligned with the side of the stem.

The Phase Flag

The Phase Flag is used in the ISTROKE command to control the “stair-stepping” pattern of the italic or diagonal stroke. The VTT compiler accomplishes this by shifting the italic stroke in quarters of a pixel in the X direction, depending on the Phase Flag value, as follows:

Phase Flag	0	1	2	3
X pixel shift	0	¼	½	¾

For the italic stroke below, shifting the stroke these fractional pixel values creates the following results:

In general, phase 3 creates the most attractive result.

MAIN_STROKE_ANGLE

MAINSTROKEANGLE(angleValue*100)

Abbreviation: M

Command Type: Informative

The MAINSTROKEANGLE command is an informative command identifying the angle of the glyphs in a font. For example, the main stroke angle of Times New Roman is 90 degrees; thus,

MAINSTROKEANGLE(9000)

This command is used when controlling an italic stroke with the STROKE command. The new ISTROKE command uses the italic_run value in the CVT instead of the main stroke angle.

If used, the main stroke angle must correspond with the italic_run control value in the CVT.

Use the measuring tool to calculate the main stroke angle for the font, as well as the italic run control value, by measuring the stem on a character such as “I.”

QUIT

QUIT( )

Abbreviation: Q

After compiling the VTT Talk code for a glyph, you may choose to edit the low-level TrueType instructions. Such edits will be overwritten the next time the VTT Talk is compiled for the glyph. To preserve your changes you will need to use the QUIT command.

Place the QUIT command as the first line of code in the VTT Talk window after making any changes to the compiled TrueType instructions. This will prevent the compiler from recompiling the VTT Talk for the glyph. However, note that any further changes to the glyph’s VTT Talk will not be incorporated into the TrueType instructions, unless you choose to remove the QUIT command and recompile the glyph.

SCOOP

SCOOP(point1, point2, point3)

Abbreviation: SC

Command Type: Action

point1	endpoint of feature
point2	deepest point of scoop
point3	endpoint of feature

The SCOOP command controls the shape of a shallow curve. SCOOP is similar to the ALIGN command, controlling the placement of midpoints on a line. Before using the SCOOP command, you must have touched the endpoints of the feature (point1 and point3). SCOOP controls the distance to point2 in x or y.

The SCOOP command is not commonly used, except by the autohinter.

SERIF

SERIF orderflag (serifType, point1, point2 [,additional points depending on the type of serif])

Abbreviation: SE

Summary: Identifies a serif shape

orderflag	> or <, depending on the order of the points
serifType	0, 1, 2, 3, 4 as described below
point1	point number
point2	point number
[,additional points]	additional points are listed depending on the type of serif

The SERIF command indicates the type of serif being used. The SERIF command is a high-level method of specifying a collection of links which control various serif designs. The SERIF command is not commonly used, except by the autohinter.

The SERIF instruction requires that certain points on the outline have already been set. For instance, at the base of an “I” the 2 points on the baseline must have their height fixed since this value is used in controlling the thickness of the serif. Similarly, the width of the stem must have been controlled before the serif instruction, since the stem width is used to set the serif length. The small arrows in the serifType illustration which follows indicate which points have to be touched and in which axis the points are positioned before the serif command is used.

The orderflag which directly follows the SERIF command indicates whether the point numbers which follow are in ascending or descending order. If the point numbers are ordered as 10, 11, 12, 13, 14, the > symbol is used. If the point numbers are ordered as 14, 13, 12, 11, 10, the < symbol would be used.

To date, there are 5 serifType flags that you may use, as illustrated below and described on the next page.

SerifType 0 is found in fonts like Times and is present in the characters “CSG.” For this serif, seven point numbers must follow the serifType, i.e. SERIF>(0,0,1,2,3,4,5,6).

SerifType 1 is also a Times serif found on the lower case characters “bdhijl.” This serif type has four points, i.e. SERIF>(1,0,1,2,4).

SerifType 2 is the main vertical stem serif which occurs in characters “IHJLT.” This serif type needs to be stated in two halves, also allowing you to use the same command for the serifs on the B and D characters, where only half of the serif illustrated above is required. To describe the left half of the serif use SERIF<(2,3,2,1,0), and for the right half use SERIF>(2,2,3,4,5).

SerifType 3 is a diagonal Times serif, present in the characters “AKVWXY.” This serif type is similar to type 2 as it is also described in two halves. The left half would be described as SERIF>(3,2,3,4,5), and the right half as SERIF<(3,3,2,1,0).

SerifType 4 is the Courier serif, which also is described in two halves. The left half is described as SERIF>(4,4,5,6,7,8,9), and the right half as SERIF<(4,5,4,3,2,1,0). When hinting Courier, this serif type is also used for diagonal stems adjoined to serifs, such as in the characters “XVAYW.”

SET_ITALIC_STROKE_ANGLE ( )

SET_ITALIC_STROKE_PHASE ( )

These commands influence the way the STROKE command controls diagonal strokes. In previous versions of VTT Talk, the STROKE command was the best way of controlling diagonal strokes. However, diagonal strokes and italic stems can now be controlled with the DSTROKE and ISTROKE commands, respectively.

By using the SET_ITALIC_STROKE_ANGLE command, you are telling the compiler to regularize the angle of italic strokes in the font. The angle value used is known as the “adjusted italic angle,” which is the italic angle adjusted so that the endpoints of the stroke fall on the grid. This causes the rise and run values of the slope to be integral.

Using the SET_ITALIC_STROKE_PHASE command tells the compiler to regularize the phase of italic strokes in the font. The phase setting used is phase 0. You can obtain alternate stair-step effects using the ISTROKE command with its phase parameter, instead of the STROKE command.

SMOOTH

SMOOTH( )

Abbreviation: SM

This instruction does a smoothing operation to all the untouched points in the x and y direction. The instruction should not be used in glyphs where every point has been hinted in x and y, since it would only make things bigger and slower.

SMOOTH is commonly used as the last VTT Talk command for a glyph.

STROKE

STROKE controlflags (point1, point2, point3, point4 [,cvt1])

Abbreviation: ST

point1	bottom left control point of stroke
point2	bottom right control point of stroke
point3	top left control point of stroke
point4	top right control point of stroke
cvt1

In previous versions of VTT Talk, the STROKE command was the best way of controlling diagonal strokes. However, diagonal strokes can now also be controlled with the DSTROKE and ISTROKE commands.

The STROKE command also was useful as an informative command when identifying horizontal or vertical strokes. However, we now advise that you use the YSTROKE and XSTROKE commands to unambiguously identify horizontal and vertical strokes. This will allow the compiler to properly interpret XLINK and YLINK commands for the stroke.

When used with the commands SET_ITALIC_STROKE_ANGLE and SET_ITALIC_STROKE_PHASE, STROKE hints a feature by extrapolating the bottom pair of control points to the baseline. This may not give the best results when hinting a diagonal feature with a serif. For serif italic features, use the ISTROKE command, which hints the feature by extrapolating the control points to the bottom of the top serif, or the top of the bottom serif, not all the way to the baseline or cap height.

When working with diagonal strokes, the two stationary points (as specified by the controlflags) should be fixed both horizontally and vertically before the STROKE command is used.

VACUFORMLIMIT

VACUFORMROUND

VACUFORMLIMIT(ppem)

VACUFORMROUND flags (cvt1, cvt2, point1, point2, point3, point4)

Abbreviation: VACUFORMR

Command Type: Action

The VACUFORMROUND command forces circular curves into an octagonal shape. This is very easy to grid fit with a consistent line width as it contains only horizontal , vertical, and 45 degree lines. Because of the simplicity of the shapes, this command can ensure that curves of a single pixel remain exactly a single pixel in width.

You will probably never author a VACUFORMROUND command yourself, as the required parameters are complex. However, you will use VACUFORMROUND commands that the autohinter generates. For a single O shape, four VACUFORMROUND commands will be generated, each controlling the “curve” from one side of the octagon to the next.

This command will only be executed if the line width is the same as the minimum width. This will usually be set to one pixel. If the line width is larger than the minimum width, this command is ignored.

Parameters describing the curve and radius values are difficult to compute, so the VACUFORMROUND command requires special control values in the CVT, as well as specific storage numbers in the preprogram. It is difficult to manually create all values needed for this command to work properly, so we suggest using this command only when it is generated by the autohinter.

The VACUFORMLIMIT command as an informative command that may preceed the VACUFORMROUND command. VACUFORMLIMIT turns off VACUFORMROUND starting at the ppem size specified.

XANCHOR

XANCHOR [angleFlag] (point1)

Abbreviation: XA

Command Type: Action

angleFlag	italic or adjusted italic angle
point1	point to anchor

The XANCHOR command rounds the specified point to the grid according to the rounding state, effectively anchoring the point. This command is usually used prior to a series of LINK commands, anchoring the “grandfather” point. If you create a series of links that begins from a sidebearing point, you do not need to use the XANCHOR command.

The YANCHOR command works somewhat differently, allowing you to specify an optional CVT number (height) at which to anchor the point.

XDELTA

XDELTA(point1, dist@ppemRange [,dist@ppemRange]...)

Abbreviation: XDE

point1	point number to move
dist@ppemRange	fractional number of pixels to shift point1 within ppem size range
dist@ppemRange	additional pixel shift values and ppem size ranges

The XDELTA command is used to shift points a specified number of pixels along the x axis at a specific ppem size or range of sizes.

Distances to be shifted can be expressed as fractions or decimal values (1/8 or .125). Ranges are expressed as begin..end;additional.

For example, to move point number 9 the distance of 1/8 pixel for ppem sizes 6, 7, 8, and 11:

XDELTA(9, 1/8@6..8;11)

Points are usually shifted in eighths of a pixel (i.e., 1/8, -1/8, 5/8), although the rasterizer can shift a point in increments of 1/64 of a pixel.

Use DELTA commands carefully, as they can potentially generate a lot of low-level code upon compilation.

XDIST

XDIST(point1, point2, [minimumDistance])

Abbreviation: XDI

Command Type: Action

point1	point number
point2	point number
minimumDistance	minimum distance flag and optional parameters (see “General Flags and Parameters”)

The XDIST command controls the horizontal distance between point1 and point2. If you omit the minimumDistance flag and parameters, the compiler will use the default minimum distances: 1/2 or 1 pixel for black features (depending on rounding state); and 0 pixels for gray and white features.

X_DOUBLE_GRID

XDOUBLEGRID(point1 [,pointn]...)

Abbreviation: XDOU

Command Type: Informative

point1	point to round
pointn	additional points to round

The XDOUBLEGRID command controls the rounding state for a specified point or series of points. Subsequent LINK or ANCHOR commands will move the points along the x axis to the nearest grid line or half grid line, whichever is closest to the point.

X_DOWN_TO_GRID

XDOWNTOGRID(point1 [,pointn]...)

Abbreviation: XDOW

Command Type: Informative

point1	point to round
pointn	additional points to round

The XDOWNTOGRID command controls the rounding state for a specified point or series of points. Subsequent LINK or ANCHOR commands will move the points down along the x axis (left) to the nearest grid line.

X_HALF_GRID

XHALFGRID(point1 [,pointn]...)

Abbreviation: XH

Command Type: Informative

point1	point to round
pointn	additional points to round

The XHALFGRID command controls the rounding state for a specified point or series of points. Subsequent LINK or ANCHOR commands will move the points midway between the vertical pixel boundaries.

XINTERPOLATE

XINTERPOLATE [angleFlag] (parentA, child1 [,childn]..., parentB)

Abbreviation: XIN

Command Type: Action

parentA	endpoint of line
child1	point to be interpolated
childn	additional points to be interpolated
parentB	endpoint of line

The XINTERPOLATE command moves the specified child points so that they maintain the same relationship (proportional distance) in x with the hinted parent point.

The child points must fall within the x interval defined by the parent points.

If the angleFlag is absent, XINTERPOLATE works purely in the x direction.

XIPANCHOR

XIPANCHOR [angleFlag] (parentA, child1 [,childn]..., parentB)

Abbreviation: XIP

Command Type: Action

parentA	endpoint of line
child1	point to be interpolated
childn	additional points to be interpolated
parentB	endpoint of line

XIPANCHOR combines the INTERPOLATE and ANCHOR commands. The command first interpolates the child points and then rounds them to the grid according to the rounding state, effectively anchoring the child points.

As with the XINTERPOLATE command, the child points must fall within the x interval defined by the parent points.

If the angleFlag is absent, XIPANCHOR works purely in the x direction.

XLINK

XLINK [angleFlag] (point1, point2 [,cvt1] [,minimumDistance])

Abbreviation: XL

Command Type: Action

angleFlag	italic or adjusted italic angle
point1	point number
point2	point number
cvt1	CVT number specifying distance value
minimumDistance	minimum distance in pixels

XLINK controls the horizontal distance between two points. You can either specify a CVT number for the distance, or allow the XLINK command to find and use the closest CVT value based on the character group and feature type (as specified in the CVT comments). A previously used XROUND or XSTROKE command will influence the control value chosen upon compilation. You must label glyph features with such informative commands for the compiler to choose correct control values.

The minimumDistance parameter forces the feature identified by the XLINK command to have a minimum width. By default, black features have a minimum distance of 1 pixel, and white (and gray) features have a minimum distance of 0 pixels.

The default values for minimum distance depend on the rounding method in use. A MinimumDistance of ½ pixel may be used to comply with previously used rounding methods.

If you want to force the distance between two points (as specified by the outline) to be preserved, use the XDIST and YDIST commands, not the LINK commands.

XMOVE

XMOVE(value, point1 [,pointn]...)

Abbreviation: XM

Command Type: Action

value	number of pixels (may be fractional)
point1	point number to move
pointn	additional point numbers to move

Moves one or more points along the x axis by a specific pixel amount, e.g., 1, 0.5, 1.25

For example, to move point 19 by ¼ of a pixel in the x direction, use:

XMOVE(0.25,19)

XROUND

XROUND(point1, point2)

Abbreviation: XR

Command Type: Informative

The XROUND command is an informative command used to identify curves. Identifying the curves helps the compiler choose a control value from the CVT that a subsequent LINK command will use.

For example:

XROUND(1,2)

XSHIFT

XSHIFT(parent1, child1 [,childn]...)

Abbreviation: XSH

Command Type: Action

parent1	parent point
child1	child point to shift
childn	additional child points

The XSHIFT command shifts the specified child points in the x direction by the same amount as the parent has been moved during previous hinting.

XSTROKE

XSTROKE(point1, point2, point3, point4 [,cvt1])

Abbreviation: XST

Command Type: Informative

point1	bottom left point
point2	bottom right point
point3	top left point
point4	top right point
cvt1	width of stroke

This command identifies a feature as a vertical stroke. This enables a subsequent LINK command to choose the appropriate control value.

X_UP_TO_GRID

XUPTOGRID(point1 [,pointn]...)

Abbreviation: XU

Command Type: Informative

point1	point to round
pointn	additional points to round

The XUPTOGRID command controls the rounding state for a specified point or series of points. Subsequent LINK or ANCHOR commands will move the points up along the x axis (right) to the nearest grid line.

YANCHOR

YANCHOR [angleFlag] (point1 [,cvt1])

Abbreviation: YA

Command Type: Action

angleFlag	italic or adjusted italic angle
point1	point to anchor
cvt1	control value number (a height value)

The YANCHOR command rounds the specified point to the grid according to the rounding state, effectively anchoring the point. This command is usually used prior to a series of LINK commands, anchoring the “grandfather” point.

The YANCHOR command allows you to specify an optional CVT number (a height value) at which to anchor the point. For example, you may anchor a point to the cap height control value. If you do not specify a CVT number, the compiler determines the height at which to anchor the point by evaluating the unhinted outline.

Using the YANCHOR command with the cvt parameter is the equivalent of using a combination of the HEIGHT command and the YANCHOR command. For example, YANCHOR (7,8) is the equivalent of:

HEIGHT (7,8)

YANCHOR (7)

YDELTA

YDELTA(point1, dist@ppemRange [,dist@ppemRange]...)

Abbreviation: XDE

point1	point number to move
dist@ppemRange	fractional number of pixels to shift point1 within ppem size range
dist@ppemRange	additional pixel shift values and ppem size ranges

The YDELTA command is used to shift points a specified number of pixels along the y axis at a specific ppem size or range of sizes.

Distances to be shifted can be expressed as fractions or decimal values (1/8 or .125). Ranges are expressed as beginValue..endValue;additionalValues.

For example, to move point number 9 the distance of 1/8 pixel for ppem sizes 6, 7, 8, and 11, write:

YDELTA(9, 1/8@6..8;11)

Points are usually shifted in eighths of a pixel (i.e., 1/8, -1/8, 5/8), although the rasterizer can shift a point in increments of 1/64 of a pixel.

Use DELTA commands carefully, as they can potentially generate a lot of low-level code upon compilation.

YDIST

YDIST(point1, point2, [minimumDistance])

Abbreviation: YDI

Command Type: Action

point1	point number
point2	point number
[minimumDistance]	minimum distance flag and optional parameters (see “General Flags and Parameters”)

The YDIST command controls the vertical distance between point1 and point2. If you omit the minimumDistance flag and parameters, the compiler will use the default minimum distances: 1/2 or 1 pixel for black features (depending on rounding state); and 0 pixels for gray and white features.

Y_DOUBLE_GRID

YDOUBLEGRID(point1 [,pointn]...)

Abbreviation: YDOU

Command Type: Informative

point1	point to round
pointn	additional points to round

The YDOUBLEGRID command controls the rounding state for a specified point or series of points. Subsequent LINK or ANCHOR commands will move the points along the y axis to the nearest grid line or half grid line, whichever is closest to the point.

Y_DOWN_TO_GRID

YDOWNTOGRID(point1 [,pointn]...)

Abbreviation: YDOW

Command Type: Informative

point1	point to round
pointn	additional points to round

The YDOWNTOGRID command controls the rounding state for a specified point or series of points. Subsequent LINK or ANCHOR commands will move the points down along the y axis to the nearest grid line.

Y_HALF_GRID

YHALFGRID(point1 [,pointn]...)

Abbreviation: YH

Command Type: Informative

point1	point to round
pointn	additional points to round

The YHALFGRID command controls the rounding state for a specified point or series of points. Subsequent LINK or ANCHOR commands will move the points midway between the horizontal pixel boundaries.

YINTERPOLATE

YINTERPOLATE [angleFlag] (parentA, child1 [,childn]..., parentB)

Abbreviation: YIN

Command Type: Action

parentA	endpoint of line
child1	point to be interpolated
childn	additional points to be interpolated
parentB	endpoint of line

The YINTERPOLATE command moves the specified child points so that they maintain the same relationship (proportional distance) in y with the hinted parent point.

The child points must fall within the y interval defined by the parent points.

If the angleFlag is absent, YINTERPOLATE works purely in the y direction.

YIPANCHOR

YIPANCHOR [angleFlag] (parentA, child1 [,childn]..., parentB)

Abbreviation: YIP

Command Type: Action

parentA	endpoint of line
child1	point to be interpolated
childn	additional points to be interpolated
parentB	endpoint of line

YIPANCHOR combines the INTERPOLATE and ANCHOR commands. The command first interpolates the child points and then rounds them to the grid according to the rounding state, effectively anchoring the child points.

As with the YINTERPOLATE command, the child points must fall within the x interval defined by the parent points.

If the angleFlag is absent, YIPANCHOR works purely in the y direction.

YLINK

YLINK [angleFlag] (point1, point2 [,cvt1] [,minimumDistance])

Abbreviation: YL

Command Type: Action

angleFlag	italic or adjusted italic angle
point1	point number
point2	point number
cvt1	CVT number specifying distance value
minimumDistance	minimum distance in pixels

YLINK controls the horizontal distance between two points. You can either specify a CVT number for the distance, or allow the YLINK command to find and use the closest CVT value based on the character group and feature type (as specified in the CVT comments). A previously used YROUND or YSTROKE command may influence the control value chosen upon compilation. You must label glyph features with such informative commands for the compiler to choose correct control values.

The minimumDistance parameter forces the feature identified by the YLINK command to have a minimum width. By default, black features have a minimum distance of 1 pixel, and white (and gray) features have a minimum distance of 0 pixels.

The default values for minimum distance depend on the rounding method in use. A MinimumDistance of 1/2 pixel may be used to comply with previously used rounding methods.

If you want to force the distance between two points (as specified by the outline) to be preserved, use the XDIST and YDIST commands, not the LINK commands.

YMOVE

YMOVE(value, point1 [,pointn]...)

Abbreviation: YM

Command Type: Action

value	number of pixels (may be fractional)
point1	point number to move
pointn	additional point numbers to move

Moves one or more points along the y axis by a specific pixel amount, e.g., 1, 0.5, 1.25

For example, to move point 19 by 1/4 of a pixel in the y direction, use:

YMOVE(0.25,19)

YROUND

YROUND(point1, point2)

Abbreviation: YR

Command Type: Informative

The YROUND command is an informative command used to identify curves. This assists the compiler in choosing control values associated with curves. These compiler will use these values in a subsequent LINK command

For example:

YROUND(3,4)

YSHIFT

YSHIFT(parent1, child1 [,childn]...)

Abbreviation: YSH

Command Type: Action

parent1	parent point
child1	child point to shift
childn	additional child points

The YSHIFT command shifts the specified child points in the y direction by the same amount as the parent has been moved during previous hinting.

YSTROKE

YSTROKE(point1, point2, point3, point4 [,cvt1])

Abbreviation: YST

Command Type: Informative

point1	top left point
point2	bottom left point
point3	top right point
point4	bottom right point
cvt1	width of stroke

This command identifies a feature as a horizontal stroke. This enables a subsequent LINK command to choose the appropriate control value.

Y_UP_TO_GRID

YUPTOGRID(point1 [,point2]...)

Abbreviation: YU

point1	point to round
pointn	additional points to round

The YUPTOGRID command controls the rounding state for a specified point or series of points. Subsequent LINK or ANCHOR commands will move the points up along the y axis to the nearest grid line.