Class: Fontisan::Subset::TableStrategy::ColorBitmapSubsetPlan

Inherits:
Object
  • Object
show all
Defined in:
lib/fontisan/subset/table_strategy/color_bitmap_subset_plan.rb

Overview

Plan for the subset of color bitmaps: which source strikes have any surviving glyph, and the per-strike runs of surviving new GIDs. Built once by [ColorBitmapSubsetter] from a CBLC + a GlyphMapping, then used to drive both CBDT and CBLC emission.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(mapping) ⇒ ColorBitmapSubsetPlan

Returns a new instance of ColorBitmapSubsetPlan.



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# File 'lib/fontisan/subset/table_strategy/color_bitmap_subset_plan.rb', line 13

def initialize(mapping)
  @mapping = mapping
  @strikes = []
  @strike_plans = []
  @placements = []
end

Instance Attribute Details

#placements ⇒ Object (readonly)

Returns the value of attribute placements.



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# File 'lib/fontisan/subset/table_strategy/color_bitmap_subset_plan.rb', line 11

def placements
  @placements
end

#strike_plans ⇒ Object (readonly)

Returns the value of attribute strike_plans.



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# File 'lib/fontisan/subset/table_strategy/color_bitmap_subset_plan.rb', line 11

def strike_plans
  @strike_plans
end

#strikes ⇒ Object (readonly)

Returns the value of attribute strikes.



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# File 'lib/fontisan/subset/table_strategy/color_bitmap_subset_plan.rb', line 11

def strikes
  @strikes
end

Instance Method Details

#collect!(cblc) ⇒ Object

Walk every (gid, strike) location in CBLC and capture the ones whose source gid is in the subset. Remaps the gid via the supplied mapping.



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# File 'lib/fontisan/subset/table_strategy/color_bitmap_subset_plan.rb', line 23

def collect!(cblc)
  cblc.bitmap_sizes.each do |strike|
    strike_plan = ColorBitmapStrikePlan.new(strike)

    cblc.sub_tables_for(strike).each do |sub|
      sub.locations.each do |loc|
        new_gid = @mapping.new_id(loc.glyph_id)
        next unless new_gid

        placement = ColorBitmapPlacement.new(
          source_gid: loc.glyph_id,
          new_gid: new_gid,
          source_offset: loc.cbdt_offset,
          byte_length: loc.byte_length,
          image_format: loc.image_format,
          strike_ppem: strike.ppem,
        )
        @placements << placement
        strike_plan.add(placement)
      end
    end

    next if strike_plan.empty?

    @strikes << strike
    @strike_plans << strike_plan
  end
end

#each_placement ⇒ Object 



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# File 'lib/fontisan/subset/table_strategy/color_bitmap_subset_plan.rb', line 52

def each_placement(&)
  @placements.each(&)
end

#each_strike_plan ⇒ Object 



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# File 'lib/fontisan/subset/table_strategy/color_bitmap_subset_plan.rb', line 56

def each_strike_plan(&)
  @strike_plans.each(&)
end