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yMax and usWinAscent calculation error

See original GitHub issue

This will cause the line height in Windows to be too large. https://github.com/thx/iconfont-plus/issues/1953#issuecomment-834044570

I guess it is a problem introduced by(v2.1.0) https://github.com/fontello/svg2ttf/issues/25 , and there is a problem with the conversion of the cubic2quad module.

In the result returned by cubic2quad, 32147.26312251112 is abnormal.

[ 'Q', 566.970047, 32147.26312251112, 567.27723, 693.5669409999996 ]

https://github.com/fontello/svg2ttf/blob/df30be9043ccb9d00e1c9087b21f084a8fface4f/lib/svg.js#L96-L111

Test file and test case in:

https://github.com/fontello/svg2ttf/pull/102/commits/ae425be18907eb9e93ceca2ecfd8ac73dcba77fd

<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd" >
<svg>
    <metadata>
        iconfont
    </metadata>
    <defs>
        <font id="iconfont" horiz-adv-x="1024">
            <font-face font-family="iconfont" font-weight="500" font-stretch="normal" units-per-em="1024" ascent="896" descent="-128" />
            <missing-glyph />
            <glyph glyph-name="up" unicode="&#58880;" d="M566.970047-68.244874V693.362153c0 0.204788 0.307182 0.307182 0.307183 0.204788l259.773733-287.42013c13.61841-14.949533 33.79004-21.195571 52.835335-16.178261a56.521522 56.521522 0 0 1 39.524108 40.548048 61.02686 61.02686 0 0 1-13.208834 56.623916L552.634879 878.285827A53.654488 53.654488 0 0 1 513.110771 896a53.654488 53.654488 0 0 1-39.524107-17.816567L117.767301 485.092633A60.207708 60.207708 0 0 1 102.408192 443.41825a59.798132 59.798132 0 0 1 16.89502-40.957625c21.912329-22.219511 56.521522-21.502753 77.614698 1.638305L456.691644 691.314272h0.307182v-760.787875c0-31.230189 22.833876-56.521522 51.401818-58.364614 15.359109-0.819152 30.308642 5.119703 41.367201 16.383049a61.231649 61.231649 0 0 1 17.099808 43.210294z" horiz-adv-x="1024" />
        </font>
    </defs>
</svg>

TTX file

<?xml version="1.0" encoding="UTF-8"?>
<ttFont sfntVersion="\x00\x01\x00\x00" ttLibVersion="4.22">
  <GlyphOrder>
    <GlyphID id="0" name="glyph00000"/>
    <GlyphID id="1" name="up"/>
  </GlyphOrder>

  <head>
    <tableVersion value="1.0"/>
    <fontRevision value="1.0"/>
    <checkSumAdjustment value="0xd03dc53e"/>
    <magicNumber value="0x5f0f3cf5"/>
    <flags value="00000000 00001011"/>
    <unitsPerEm value="1024"/>
    <created value="Sat May  8 11:35:08 2021"/>
    <modified value="Sat May  8 11:35:08 2021"/>
    <xMin value="0"/>
    <yMin value="-130"/>
    <xMax value="1024"/>
    <yMax value="32148"/>
    <macStyle value="00000000 00000000"/>
    <lowestRecPPEM value="8"/>
    <fontDirectionHint value="2"/>
    <indexToLocFormat value="0"/>
    <glyphDataFormat value="0"/>
  </head>

  <hhea>
    <tableVersion value="0x00010000"/>
    <ascent value="896"/>
    <descent value="-128"/>
    <lineGap value="0"/>
    <advanceWidthMax value="1024"/>
    <minLeftSideBearing value="0"/>
    <minRightSideBearing value="0"/>
    <xMaxExtent value="1024"/>
    <caretSlopeRise value="1"/>
    <caretSlopeRun value="0"/>
    <caretOffset value="0"/>
    <reserved0 value="0"/>
    <reserved1 value="0"/>
    <reserved2 value="0"/>
    <reserved3 value="0"/>
    <metricDataFormat value="0"/>
    <numberOfHMetrics value="2"/>
  </hhea>

  <OS_2>
    <version value="1"/>
    <xAvgCharWidth value="1024"/>
    <usWeightClass value="400"/>
    <usWidthClass value="5"/>
    <fsType value="00000000 00000000"/>
    <ySubscriptXSize value="649"/>
    <ySubscriptYSize value="716"/>
    <ySubscriptXOffset value="0"/>
    <ySubscriptYOffset value="143"/>
    <ySuperscriptXSize value="649"/>
    <ySuperscriptYSize value="716"/>
    <ySuperscriptXOffset value="0"/>
    <ySuperscriptYOffset value="491"/>
    <yStrikeoutSize value="50"/>
    <yStrikeoutPosition value="264"/>
    <sFamilyClass value="0"/>
    <panose>
      <bFamilyType value="2"/>
      <bSerifStyle value="0"/>
      <bWeight value="5"/>
      <bProportion value="3"/>
      <bContrast value="0"/>
      <bStrokeVariation value="0"/>
      <bArmStyle value="0"/>
      <bLetterForm value="0"/>
      <bMidline value="0"/>
      <bXHeight value="0"/>
    </panose>
    <ulUnicodeRange1 value="00000000 00000000 00000000 00000000"/>
    <ulUnicodeRange2 value="00000000 00000000 00000000 00000000"/>
    <ulUnicodeRange3 value="00000000 00000000 00000000 00000000"/>
    <ulUnicodeRange4 value="00000000 00000000 00000000 00000000"/>
    <achVendID value="PfEd"/>
    <fsSelection value="00000000 01000000"/>
    <usFirstCharIndex value="58880"/>
    <usLastCharIndex value="58880"/>
    <sTypoAscender value="896"/>
    <sTypoDescender value="-128"/>
    <sTypoLineGap value="92"/>
    <usWinAscent value="32148"/>
    <usWinDescent value="130"/>
    <ulCodePageRange1 value="00000000 00000000 00000000 00000001"/>
    <ulCodePageRange2 value="00000000 00000000 00000000 00000000"/>
  </OS_2>
  <glyf>
    <TTGlyph name="glyph00000"/><!-- contains no outline data -->
    <TTGlyph name="up" xMin="0" yMin="-130" xMax="924" yMax="32148">
      <contour>
        <pt x="567" y="-68" on="1"/>
        <pt x="567" y="693" on="1"/>
        <pt x="567" y="32147" on="0"/>
        <pt x="567" y="694" on="1"/>
        <pt x="827" y="406" on="1"/>
        <pt x="837" y="395" on="0"/>
        <pt x="866" y="386" on="0"/>
        <pt x="894" y="394" on="0"/>
        <pt x="916" y="416" on="0"/>
        <pt x="923" y="445" on="0"/>
        <pt x="916" y="476" on="0"/>
        <pt x="906" y="487" on="1"/>
        <pt x="553" y="878" on="1"/>
        <pt x="537" y="896" on="0"/>
        <pt x="489" y="896" on="0"/>
        <pt x="474" y="878" on="1"/>
        <pt x="118" y="485" on="1"/>
        <pt x="102" y="467" on="0"/>
        <pt x="103" y="420" on="0"/>
        <pt x="136" y="386" on="0"/>
        <pt x="181" y="387" on="0"/>
        <pt x="197" y="404" on="1"/>
        <pt x="457" y="691" on="1"/>
        <pt x="457" y="-69" on="1"/>
        <pt x="457" y="-93" on="0"/>
        <pt x="487" y="-126" on="0"/>
        <pt x="508" y="-128" on="1"/>
        <pt x="532" y="-129" on="0"/>
        <pt x="567" y="-93" on="0"/>
      </contour>
      <instructions/>
    </TTGlyph>
  </glyf>
</ttFont>