@@ -1942,7 +1942,7 @@ <h4>Layout of operators</h4>
19421942 < code > T< sub > ascent</ sub > </ code > +
19431943 < code > T< sub > descent</ sub > </ code >
19441944 and at position determined by the previous box metrics
1945- shifted by Δ towards the < a > line-over </ a > .
1945+ shifted by Δ towards the < a > line-under </ a > .
19461946 </ li >
19471947 </ ol >
19481948 < figure id ="figure-base-variants-and-assembly ">
@@ -1961,25 +1961,65 @@ <h4>Layout of operators</h4>
19611961 then:
19621962 < ol >
19631963 < li >
1964- < p >
1965- Use the
1966- < code > MathVariants</ code >
1967- table to try and find a glyph of height at least
1968- < a > DisplayOperatorMinHeight</ a > .
1969- If none is found, fall back to the
1970- largest non-base glyph. If none is found, fall back to
1971- the layout algorithm of < a href ="#layout-of-mtext "> </ a > .
1972- </ p >
1964+ If it is not possible to < a > shape a stretchy glyph</ a >
1965+ corresponding to < code > c</ code > in the block direction
1966+ with the
1967+ < a > first available font</ a >
1968+ then fall back to the
1969+ layout algorithm of < a href ="#layout-of-mtext "> </ a > .
1970+ < div class ="note ">
1971+ Here we treat a non-[=embellished operator/stretchy=] [=embellished operator/largeop=]
1972+ glyph as stretchy with target dimension < a > DisplayOperatorMinHeight</ a > .
1973+ </ div >
19731974 </ li >
19741975 < li >
1975- The < a > min-content inline size</ a > ,
1976- < a > max-content inline size</ a > ,
1977- < a > inline size</ a > and block metrics of the math content
1978- are given by the
1979- glyph found.
1976+ The < a > min-content inline size</ a > and
1977+ < a > max-content inline size</ a > of the math content
1978+ are set to the < a > preferred inline size of a glyph
1979+ stretched along the block axis</ a > .
19801980 </ li >
19811981 < li >
1982- Paint the glyph.
1982+ The < a > inline size</ a > ,
1983+ < a > ink line-ascent</ a > ,
1984+ < a > ink line-descent</ a > ,
1985+ < a > line-ascent</ a > and
1986+ < a > line-descent</ a >
1987+ of the math content
1988+ are obtained by the algorithm to
1989+ < a > shape a stretchy glyph</ a >
1990+ to < a > block dimension</ a >
1991+ < a > DisplayOperatorMinHeight</ a > .
1992+ The < a > inline size</ a > of the math content is the width of
1993+ the stretchy glyph. The stretchy glyph is shifted
1994+ towards the < a > line-under</ a > by a value Δ so that its
1995+ center aligns with the center of the target when
1996+ [=embellished operator/symmetric=]:
1997+ the ink ascent of the math content is
1998+ the ascent of the stretchy glyph − Δ
1999+ and the ink descent of the math content is
2000+ the descent of the stretchy glyph + Δ.
2001+ < ul >
2002+ < li >
2003+ If the operator has the [=embellished operator/symmetric=] property,
2004+ then
2005+ Δ = [(ascent of stretchy glyph − descent of stretchy glyph) − 2 * < a > AxisHeight</ a > ] / 2.
2006+ </ li >
2007+ < li >
2008+ Otherwise,
2009+ Δ = 0.
2010+ </ li >
2011+ </ ul >
2012+ < div class ="note ">
2013+ The point of Δ here is simply to vertically align the operator when [=embellished operator/symmetric=].
2014+ </ div >
2015+ </ li >
2016+ < li >
2017+ The painting of the operator is performed by the
2018+ algorithm to < a > shape a stretchy glyph</ a >
2019+ stretched to < a > block dimension</ a >
2020+ < a > DisplayOperatorMinHeight</ a >
2021+ and at position determined by the previous box metrics
2022+ shifted by Δ towards the < a > line-under</ a > .
19832023 </ li >
19842024 </ ol >
19852025 < figure id ="figure-sum-base-and-displastyle-sizes ">
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