Class: TTFunk::Table::Head

Inherits:
TTFunk::Table show all
Defined in:
lib/ttfunk/table/head.rb

Overview

Font Header (head) Table.

Instance Attribute Summary collapse

Attributes inherited from TTFunk::Table

#file, #length, #offset

Class Method Summary collapse

Methods inherited from TTFunk::Table

#exists?, #initialize, #raw, #tag

Constructor Details

This class inherits a constructor from TTFunk::Table

Instance Attribute Details

#checksum_adjustment ⇒ Integer (readonly)

Checksum adjustment.

Returns:

  • (Integer)
Source Code
lib/ttfunk/table/head.rb, line 19
19
def checksum_adjustment

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  @checksum_adjustment

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end

#created ⇒ Integer (readonly)

Font creation time.

Returns:

  • (Integer) —

    Long Date Time timestamp.

Source Code
lib/ttfunk/table/head.rb, line 35
35
def created

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  @created

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end

#flags ⇒ Integer (readonly)

Flags.

Returns:

  • (Integer)
Source Code
lib/ttfunk/table/head.rb, line 27
27
def flags

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  @flags

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end

#font_direction_hint ⇒ Integer (readonly)

Font direction hint. Deprecated, set to 2.

Returns:

  • (Integer)
Source Code
lib/ttfunk/table/head.rb, line 67
67
def font_direction_hint

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  @font_direction_hint

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end

#font_revision ⇒ Integer (readonly)

Font revision.

Returns:

  • (Integer)
Source Code
lib/ttfunk/table/head.rb, line 15
15
def font_revision

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  @font_revision

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end

#glyph_data_format ⇒ Integer (readonly)

Glyph data format.

Returns:

  • (Integer)
Source Code
lib/ttfunk/table/head.rb, line 75
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def glyph_data_format

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  @glyph_data_format

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end

#index_to_loc_format ⇒ Integer (readonly)

Index to Location format.

Returns:

  • (Integer)
Source Code
lib/ttfunk/table/head.rb, line 71
71
def index_to_loc_format

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  @index_to_loc_format

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end

#lowest_rec_ppem ⇒ Integer (readonly)

Smallest readable size in pixels.

Returns:

  • (Integer)
Source Code
lib/ttfunk/table/head.rb, line 63
63
def lowest_rec_ppem

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  @lowest_rec_ppem

65
end

#mac_style ⇒ Integer (readonly)

Mac font style.

Returns:

  • (Integer)
Source Code
lib/ttfunk/table/head.rb, line 59
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def mac_style

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  @mac_style

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end

#magic_number ⇒ Integer (readonly)

Magic number.

Returns:

  • (Integer) —

    must be 0x5F0F3CF5

Source Code
lib/ttfunk/table/head.rb, line 23
23
def magic_number

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  @magic_number

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end

#modified ⇒ Integer (readonly)

Font modification time.

Returns:

  • (Integer) —

    Long Date Time timestamp.

Source Code
lib/ttfunk/table/head.rb, line 39
39
def modified

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  @modified

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end

#units_per_em ⇒ Integer (readonly)

Units per Em.

Returns:

  • (Integer)
Source Code
lib/ttfunk/table/head.rb, line 31
31
def units_per_em

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  @units_per_em

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end

#version ⇒ Integer (readonly)

Table version.

Returns:

  • (Integer)
Source Code
lib/ttfunk/table/head.rb, line 11
11
def version

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  @version

13
end

#x_max ⇒ Integer (readonly)

Maximum x coordinate across all glyph bounding boxes.

Returns:

  • (Integer)
Source Code
lib/ttfunk/table/head.rb, line 51
51
def x_max

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  @x_max

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end

#x_min ⇒ Integer (readonly)

Minimum x coordinate across all glyph bounding boxes.

Returns:

  • (Integer)
Source Code
lib/ttfunk/table/head.rb, line 43
43
def x_min

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  @x_min

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end

#y_max ⇒ Integer (readonly)

Maximum y coordinate across all glyph bounding boxes.

Returns:

  • (Integer)
Source Code
lib/ttfunk/table/head.rb, line 55
55
def y_max

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  @y_max

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end

#y_min ⇒ Integer (readonly)

Minimum y coordinate across all glyph bounding boxes.

Returns:

  • (Integer)
Source Code
lib/ttfunk/table/head.rb, line 47
47
def y_min

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  @y_min

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end

Class Method Details

.encode(head, loca, mapping) ⇒ EncodedString

Encode table.

Parameters:

  • head (TTFunk::Table::Head)
  • loca (Hash) —

    result of encoding Index to Location (loca) table

  • mapping (Hash{Integer => Integer}) —

    keys are new glyph IDs, values are old glyph IDs

Returns:

Source Code
lib/ttfunk/table/head.rb, line 92
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def encode(head, loca, mapping)

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  EncodedString.new do |table|

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    table <<

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      [head.version, head.font_revision].pack('N2') <<

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      Placeholder.new(:checksum, length: 4) <<

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      [

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        head.magic_number,

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        head.flags, head.units_per_em,

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        head.created, head.modified,

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        *min_max_values_for(head, mapping),

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        head.mac_style, head.lowest_rec_ppem, head.font_direction_hint,

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        loca[:type] || 0, head.glyph_data_format,

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      ].pack('Nn2q>2n*')

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  end

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end

.from_long_date_time(ldt) ⇒ Time

Convert Long Date Time timestamp to Time.

Parameters:

  • ldt (Float, Integer)

Returns:

  • (Time)
Source Code
lib/ttfunk/table/head.rb, line 111
111
def from_long_date_time(ldt)

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  Time.at(ldt + LONG_DATE_TIME_BASIS, in: 'UTC')

113
end

.to_long_date_time(time) ⇒ Integer

Convert Time to Long Date Time timestamp

Parameters:

  • time (Time)

Returns:

  • (Integer)
Source Code
lib/ttfunk/table/head.rb, line 118
118
def to_long_date_time(time)

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  Integer(time) - LONG_DATE_TIME_BASIS

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end