Module: HarfBuzz::OT::Math

Defined in:
lib/harfbuzz/ot/math.rb

Overview

OpenType Math Typesetting API

Class Method Summary collapse

Class Method Details

.constant(font, constant) ⇒ Integer

Returns a MATH constant value

Parameters:

  • font (Font) —

    Sized font

  • constant (Integer) —

    Math constant index

Returns:

  • (Integer) —

    Constant value in font units



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# File 'lib/harfbuzz/ot/math.rb', line 19

def constant(font, constant)
  C.hb_ot_math_get_constant(font.ptr, constant)
end

.glyph_assembly(font, glyph, dir) ⇒ Hash

Returns math glyph assembly (extensible glyph parts)

Parameters:

  • font (Font) —

    Sized font

  • glyph (Integer) —

    Glyph ID

  • dir (Symbol) —

    Direction

Returns:

  • (Hash) —

    { parts: Array<C::HbOtMathGlyphPartT>, italics_correction: Integer }



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# File 'lib/harfbuzz/ot/math.rb', line 80

def glyph_assembly(font, glyph, dir)
  count_ptr = FFI::MemoryPointer.new(:uint)
  count_ptr.write_uint(0)
  italics_ptr = FFI::MemoryPointer.new(:int32)
  total = C.hb_ot_math_get_glyph_assembly(
    font.ptr, glyph, dir, 0, count_ptr, nil, italics_ptr
  )
  parts = if total.zero?
            []
          else
            parts_ptr = FFI::MemoryPointer.new(C::HbOtMathGlyphPartT, total)
            count_ptr.write_uint(total)
            C.hb_ot_math_get_glyph_assembly(
              font.ptr, glyph, dir, 0, count_ptr, parts_ptr, italics_ptr
            )
            actual = count_ptr.read_uint
            actual.times.map do |i|
              C::HbOtMathGlyphPartT.new(parts_ptr + i * C::HbOtMathGlyphPartT.size)
            end
          end
  { parts: parts, italics_correction: italics_ptr.read_int32 }
end

.glyph_extended_shape?(face, glyph) ⇒ Boolean

Returns true if glyph is an extended shape.

Parameters:

  • face (Face) —

    Font face

  • glyph (Integer) —

    Glyph ID

Returns:

  • (Boolean) —

    true if glyph is an extended shape



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# File 'lib/harfbuzz/ot/math.rb', line 40

def glyph_extended_shape?(face, glyph)
  C.from_hb_bool(C.hb_ot_math_is_glyph_extended_shape(face.ptr, glyph))
end

.glyph_italics_correction(font, glyph) ⇒ Integer

Returns Italics correction in font units.

Parameters:

  • font (Font) —

    Sized font

  • glyph (Integer) —

    Glyph ID

Returns:

  • (Integer) —

    Italics correction in font units



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# File 'lib/harfbuzz/ot/math.rb', line 26

def glyph_italics_correction(font, glyph)
  C.hb_ot_math_get_glyph_italics_correction(font.ptr, glyph)
end

.glyph_kerning(font, glyph, kern, correction_height) ⇒ Integer

Returns the math kerning value

Parameters:

  • font (Font) —

    Sized font

  • glyph (Integer) —

    Glyph ID

  • kern (Integer) —

    Kern type

  • correction_height (Integer) —

    Correction height

Returns:

  • (Integer) —

    Kerning value



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# File 'lib/harfbuzz/ot/math.rb', line 50

def glyph_kerning(font, glyph, kern, correction_height)
  C.hb_ot_math_get_glyph_kerning(font.ptr, glyph, kern, correction_height)
end

.glyph_top_accent_attachment(font, glyph) ⇒ Integer

Returns Top accent attachment in font units.

Parameters:

  • font (Font) —

    Sized font

  • glyph (Integer) —

    Glyph ID

Returns:

  • (Integer) —

    Top accent attachment in font units



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# File 'lib/harfbuzz/ot/math.rb', line 33

def glyph_top_accent_attachment(font, glyph)
  C.hb_ot_math_get_glyph_top_accent_attachment(font.ptr, glyph)
end

.glyph_variants(font, glyph, dir) ⇒ Array<C::HbOtMathGlyphVariantT>

Returns math glyph variants

Parameters:

  • font (Font) —

    Sized font

  • glyph (Integer) —

    Glyph ID

  • dir (Symbol) —

    Direction

Returns:



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# File 'lib/harfbuzz/ot/math.rb', line 59

def glyph_variants(font, glyph, dir)
  count_ptr = FFI::MemoryPointer.new(:uint)
  count_ptr.write_uint(0)
  C.hb_ot_math_get_glyph_variants(font.ptr, glyph, dir, 0, count_ptr, nil)
  count = count_ptr.read_uint
  return [] if count.zero?

  variants_ptr = FFI::MemoryPointer.new(C::HbOtMathGlyphVariantT, count)
  count_ptr.write_uint(count)
  C.hb_ot_math_get_glyph_variants(font.ptr, glyph, dir, 0, count_ptr, variants_ptr)
  actual = count_ptr.read_uint
  actual.times.map do |i|
    C::HbOtMathGlyphVariantT.new(variants_ptr + i * C::HbOtMathGlyphVariantT.size)
  end
end

.has_data?(face) ⇒ Boolean

Returns true if the face has a MATH table.

Parameters:

  • face (Face) —

    Font face

Returns:

  • (Boolean) —

    true if the face has a MATH table



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# File 'lib/harfbuzz/ot/math.rb', line 11

def has_data?(face)
  C.from_hb_bool(C.hb_ot_math_has_data(face.ptr))
end

.min_connector_overlap(font, dir) ⇒ Integer

Returns Minimum connector overlap in font units.

Parameters:

  • font (Font) —

    Sized font

  • dir (Symbol) —

    Direction

Returns:

  • (Integer) —

    Minimum connector overlap in font units



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# File 'lib/harfbuzz/ot/math.rb', line 106

def min_connector_overlap(font, dir)
  C.hb_ot_math_get_min_connector_overlap(font.ptr, dir)
end