NAME

Font::TTF::OS_2 - the OS/2 table in a TTF font

DESCRIPTION

The OS/2 table has two versions and forms, one an extension of the other. This module supports both forms and the switching between them.

INSTANCE VARIABLES

No other variables than those in table and those in the standard:

Version
xAvgCharWidth
usWeightClass
usWidthClass
fsType
ySubscriptXSize
ySubScriptYSize
ySubscriptXOffset
ySubscriptYOffset
ySuperscriptXSize
ySuperscriptYSize
ySuperscriptXOffset
ySuperscriptYOffset
yStrikeoutSize
yStrikeoutPosition
sFamilyClass
bFamilyType
bSerifStyle
bWeight
bProportion
bContrast
bStrokeVariation
bArmStyle
bLetterform
bMidline
bXheight
ulUnicodeRange1
ulUnicodeRange2
ulUnicodeRange3
ulUnicodeRange4
achVendID
fsSelection
usFirstCharIndex
usLastCharIndex
sTypoAscender
sTypoDescender
sTypoLineGap
usWinAscent
usWinDescent
ulCodePageRange1
ulCodePageRange2
xHeight
CapHeight
defaultChar
breakChar
maxLookups

Notice that versions 0, 1 & 2 of the table are supported. Notice also that the Panose variable has been broken down into its elements.

METHODS

$t->read

Reads in the various values from disk (see details of OS/2 table)

$t->out($fh)

Writes the table to a file either from memory or by copying.

$t->XML_element($context, $depth, $key, $value)

Tidies up the hex values to output them in hex

$t->XML_end($context, $tag, %attrs)

Now handle them on the way back in

$t->update

Updates the OS/2 table by getting information from other sources:

Updates the firstChar and lastChar values based on the MS table in the cmap.

Updates the sTypoAscender, sTypoDescender & sTypoLineGap to be the same values as Ascender, Descender and Linegap from the hhea table (assuming it is dirty) and also sets usWinAscent to be the sum of Ascender+Linegap and usWinDescent to be the negative of Descender.

BUGS

None known

AUTHOR

Martin Hosken Martin_Hosken@sil.org. See Font::TTF::Font for copyright and licensing.