svg2ttf/lib/ttf/tables/hhea.js

Converts SVG font to TTF font

'use strict'

// See documentation here: http://www.microsoft.com/typography/otspec/hhea.htm

var ByteBuffer = require('microbuffer')

function createHHeadTable (font) {
  var buf = new ByteBuffer(36) // fixed table length

  buf.writeInt32(0x10000) // version
  buf.writeInt16(font.ascent) // ascent
  buf.writeInt16(font.descent) // descend
  // Non zero lineGap causes offset in IE, https://github.com/fontello/svg2ttf/issues/37
  buf.writeInt16(0) // lineGap
  buf.writeUint16(font.maxWidth) // advanceWidthMax
  buf.writeInt16(font.minLsb) // minLeftSideBearing
  buf.writeInt16(font.minRsb) // minRightSideBearing
  buf.writeInt16(font.maxExtent) // xMaxExtent
  buf.writeInt16(1) // caretSlopeRise
  buf.writeInt16(0) // caretSlopeRun
  buf.writeUint32(0) // reserved1
  buf.writeUint32(0) // reserved2
  buf.writeUint16(0) // reserved3
  buf.writeInt16(0) // metricDataFormat
  buf.writeUint16(font.glyphs.length) // numberOfHMetrics

  return buf
}

module.exports = createHHeadTable