Module: HarfBuzz::AAT::Layout

Defined in:
lib/harfbuzz/aat/layout.rb

Overview

Apple Advanced Typography Layout queries

Class Method Summary collapse

Class Method Details

.feature_type_name_id(face, type) ⇒ Integer?

Returns the name ID for a feature type

Parameters:

  • face (Face) —

    Font face

  • type (Integer) —

    Feature type

Returns:

  • (Integer, nil) —

    Name ID or nil



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# File 'lib/harfbuzz/aat/layout.rb', line 47

def feature_type_name_id(face, type)
  name_id_ptr = FFI::MemoryPointer.new(:uint)
  ok = C.hb_aat_layout_feature_type_get_name_id(face.ptr, type, name_id_ptr)
  ok.zero? ? nil : name_id_ptr.read_uint
end

.feature_types(face) ⇒ Array<Integer>

Returns feature types available in the AAT 'feat' table

Parameters:

  • face (Face) —

    Font face

Returns:

  • (Array<Integer>) —

    Feature type values



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# File 'lib/harfbuzz/aat/layout.rb', line 30

def feature_types(face)
  count_ptr = FFI::MemoryPointer.new(:uint)
  count_ptr.write_uint(0)
  C.hb_aat_layout_get_feature_types(face.ptr, 0, count_ptr, nil)
  count = count_ptr.read_uint
  return [] if count.zero?

  types_ptr = FFI::MemoryPointer.new(:uint, count)
  count_ptr.write_uint(count)
  C.hb_aat_layout_get_feature_types(face.ptr, 0, count_ptr, types_ptr)
  types_ptr.read_array_of_uint(count_ptr.read_uint)
end

.has_positioning?(face) ⇒ Boolean

Returns true if the face has AAT kerning/kerx positioning.

Parameters:

  • face (Face) —

    Font face

Returns:

  • (Boolean) —

    true if the face has AAT kerning/kerx positioning



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# File 'lib/harfbuzz/aat/layout.rb', line 17

def has_positioning?(face)
  C.from_hb_bool(C.hb_aat_layout_has_positioning(face.ptr))
end

.has_substitution?(face) ⇒ Boolean

Returns true if the face has AAT morx substitution.

Parameters:

  • face (Face) —

    Font face

Returns:

  • (Boolean) —

    true if the face has AAT morx substitution



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# File 'lib/harfbuzz/aat/layout.rb', line 11

def has_substitution?(face)
  C.from_hb_bool(C.hb_aat_layout_has_substitution(face.ptr))
end

.has_tracking?(face) ⇒ Boolean

Returns true if the face has AAT trak tracking.

Parameters:

  • face (Face) —

    Font face

Returns:

  • (Boolean) —

    true if the face has AAT trak tracking



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# File 'lib/harfbuzz/aat/layout.rb', line 23

def has_tracking?(face)
  C.from_hb_bool(C.hb_aat_layout_has_tracking(face.ptr))
end

.selector_infos(face, type) ⇒ Array<C::HbAatLayoutFeatureSelectorInfoT>

Returns the selector infos for a feature type

Parameters:

  • face (Face) —

    Font face

  • type (Integer) —

    Feature type

Returns:



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# File 'lib/harfbuzz/aat/layout.rb', line 57

def selector_infos(face, type)
  count_ptr = FFI::MemoryPointer.new(:uint)
  count_ptr.write_uint(0)
  C.hb_aat_layout_feature_type_get_selector_infos(face.ptr, type, 0, count_ptr, nil, nil)
  count = count_ptr.read_uint
  return [] if count.zero?

  infos_ptr = FFI::MemoryPointer.new(C::HbAatLayoutFeatureSelectorInfoT, count)
  count_ptr.write_uint(count)
  C.hb_aat_layout_feature_type_get_selector_infos(
    face.ptr, type, 0, count_ptr, infos_ptr, nil
  )
  actual = count_ptr.read_uint
  actual.times.map do |i|
    C::HbAatLayoutFeatureSelectorInfoT.new(
      infos_ptr + i * C::HbAatLayoutFeatureSelectorInfoT.size
    )
  end
end