Class: Fontisan::Tables::Cblc::BitmapSize

Inherits:
Binary::BaseRecord show all
Defined in:
lib/fontisan/tables/cblc.rb

Overview

BitmapSize record structure (48 bytes)

Describes a bitmap strike at a specific ppem size

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Binary::BaseRecord

#raw_data, #valid?

Instance Attribute Details

#bit_depth ⇒ Object (readonly)

Returns the value of attribute bit_depth.



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# File 'lib/fontisan/tables/cblc.rb', line 115

def bit_depth
  @bit_depth
end

#color_ref ⇒ Object (readonly)

Returns the value of attribute color_ref.



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# File 'lib/fontisan/tables/cblc.rb', line 115

def color_ref
  @color_ref
end

#end_glyph_index ⇒ Object (readonly)

Returns the value of attribute end_glyph_index.



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# File 'lib/fontisan/tables/cblc.rb', line 115

def end_glyph_index
  @end_glyph_index
end

#flags ⇒ Object (readonly)

Returns the value of attribute flags.



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# File 'lib/fontisan/tables/cblc.rb', line 115

def flags
  @flags
end

#hori ⇒ Object (readonly)

Returns the value of attribute hori.



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# File 'lib/fontisan/tables/cblc.rb', line 115

def hori
  @hori
end

#index_subtable_array_offset ⇒ Object (readonly)

Returns the value of attribute index_subtable_array_offset.



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# File 'lib/fontisan/tables/cblc.rb', line 115

def index_subtable_array_offset
  @index_subtable_array_offset
end

#index_tables_size ⇒ Object (readonly)

Returns the value of attribute index_tables_size.



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# File 'lib/fontisan/tables/cblc.rb', line 115

def index_tables_size
  @index_tables_size
end

#number_of_index_subtables ⇒ Object (readonly)

Returns the value of attribute number_of_index_subtables.



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# File 'lib/fontisan/tables/cblc.rb', line 115

def number_of_index_subtables
  @number_of_index_subtables
end

#ppem_x ⇒ Object (readonly)

Returns the value of attribute ppem_x.



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# File 'lib/fontisan/tables/cblc.rb', line 115

def ppem_x
  @ppem_x
end

#ppem_y ⇒ Object (readonly)

Returns the value of attribute ppem_y.



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# File 'lib/fontisan/tables/cblc.rb', line 115

def ppem_y
  @ppem_y
end

#start_glyph_index ⇒ Object (readonly)

Returns the value of attribute start_glyph_index.



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# File 'lib/fontisan/tables/cblc.rb', line 115

def start_glyph_index
  @start_glyph_index
end

#vert ⇒ Object (readonly)

Returns the value of attribute vert.



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# File 'lib/fontisan/tables/cblc.rb', line 115

def vert
  @vert
end

Class Method Details

.read(io) ⇒ Object

Read the SbitLineMetrics structures manually



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# File 'lib/fontisan/tables/cblc.rb', line 84

def self.read(io)
  data = io.is_a?(String) ? io : io.read
  size = new

  io = StringIO.new(data)
  size.instance_variable_set(:@index_subtable_array_offset,
                             io.read(4).unpack1("N"))
  size.instance_variable_set(:@index_tables_size,
                             io.read(4).unpack1("N"))
  size.instance_variable_set(:@number_of_index_subtables,
                             io.read(4).unpack1("N"))
  size.instance_variable_set(:@color_ref, io.read(4).unpack1("N"))

  # Parse hori and vert metrics (12 bytes each)
  hori_data = io.read(12)
  vert_data = io.read(12)
  size.instance_variable_set(:@hori, SbitLineMetrics.read(hori_data))
  size.instance_variable_set(:@vert, SbitLineMetrics.read(vert_data))

  # Parse remaining fields
  size.instance_variable_set(:@start_glyph_index,
                             io.read(2).unpack1("n"))
  size.instance_variable_set(:@end_glyph_index, io.read(2).unpack1("n"))
  size.instance_variable_set(:@ppem_x, io.read(1).unpack1("C"))
  size.instance_variable_set(:@ppem_y, io.read(1).unpack1("C"))
  size.instance_variable_set(:@bit_depth, io.read(1).unpack1("C"))
  size.instance_variable_set(:@flags, io.read(1).unpack1("c"))

  size
end

Instance Method Details

#glyph_range ⇒ Range

Get glyph range for this strike

Returns:

  • (Range) —

    Range of glyph IDs



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# File 'lib/fontisan/tables/cblc.rb', line 130

def glyph_range
  start_glyph_index..end_glyph_index
end

#includes_glyph?(glyph_id) ⇒ Boolean

Check if this strike includes a specific glyph ID

Parameters:

  • glyph_id (Integer) —

    Glyph ID to check

Returns:

  • (Boolean) —

    True if glyph is in range



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# File 'lib/fontisan/tables/cblc.rb', line 138

def includes_glyph?(glyph_id)
  glyph_range.include?(glyph_id)
end

#ppem ⇒ Integer

Get ppem size (assumes square pixels)

Returns:

  • (Integer) —

    Pixels per em



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# File 'lib/fontisan/tables/cblc.rb', line 123

def ppem
  ppem_x
end