# Font::TTF::Delta - phpMan

## NAME
    [Font::TTF::Delta] - Opentype Device tables

## DESCRIPTION
    Each device table corresponds to a set of deltas for a particular point
    over a range of ppem values.

    first
        The first ppem value in the range

    last
        The last ppem value in the range

    val This is an array of deltas corresponding to each ppem in the range
        between first and last inclusive.

    fmt This is the fmt used (log2 of number bits per value) when the device
        table was read. It is recalculated on output.

## METHODS
  new
    Creates a new device table

  read
    Reads a device table from the given IO object at the current location

  out($fh, $style)
    Outputs a device table to the given IO object at the current location,
    or just returns the data to be output if $style != 0

  $d->signature()
    Returns a content based identifying string for this delta for
    compression purposes

  $d->out_xml($context)
    Outputs a delta in XML

## AUTHOR
    Martin Hosken <<http://scripts.sil.org/FontUtils>>.

## LICENSING
    Copyright (c) 1998-2016, SIL International (<http://www.sil.org>)

    This module is released under the terms of the Artistic License 2.0. For
    details, see the full text of the license in the file LICENSE.