Class: Fontisan::Commands::OpticalSizeCommand

Inherits:
BaseCommand
  • Object
show all
Defined in:
lib/fontisan/commands/optical_size_command.rb

Overview

Command to extract optical size information from fonts

Optical size information indicates the design size range for which a font is optimized. This information can come from:

  • OS/2 table version 5+ (usLowerOpticalPointSize, usUpperOpticalPointSize)
  • GPOS 'size' feature (not yet implemented)

Instance Method Summary collapse

Methods inherited from BaseCommand

#initialize

Constructor Details

This class inherits a constructor from Fontisan::Commands::BaseCommand

Instance Method Details

#run ⇒ Models::OpticalSizeInfo

Execute the optical size extraction command

Returns:



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# File 'lib/fontisan/commands/optical_size_command.rb', line 15

def run
  result = Models::OpticalSizeInfo.new

  # Try OS/2 table first
  if font.has_table?(Constants::OS2_TAG)
    os2_table = font.table(Constants::OS2_TAG)

    if os2_table.has_optical_point_size?
      result.has_optical_size = true
      result.source = "os2"
      result.lower_point_size = os2_table.lower_optical_point_size
      result.upper_point_size = os2_table.upper_optical_point_size
      return result
    end
  end

  # No optical size information
  result.has_optical_size = false
  result.source = "none"
  result
end