math2html: Improve handling of big symbols.

Scale variable sized operators with CSS instead of constructing from pieces.

Fix Unicode translations for N-ary operators.

Scale stretch big delimiters instead of scaling.

git-svn-id: https://svn.code.sf.net/p/docutils/code/trunk@8796 929543f6-e4f2-0310-98a6-ba3bd3dd1d04

4 files changed, 69 insertions, 55 deletions

diff --git a/docutils/docs/ref/rst/mathematics.txt b/docutils/docs/ref/rst/mathematics.txt
index 5901d6e8e..278eb444d 100644
--- a/docutils/docs/ref/rst/mathematics.txt
+++ b/docutils/docs/ref/rst/mathematics.txt
@@ -989,6 +989,7 @@ with extensible delimiters.
    \left.\vert \frac{b}{a}\right\Vert\ \bigl\vert b\Bigr\Vert\ \biggl\vert b\Biggr\Vert
    \quad
 
+
 Variable-sized operators:
 
 Inline: `\sum\ \int\ \oint\ \smallint\ \prod\ \coprod\ \bigwedge\
diff --git a/docutils/docutils/utils/math/math2html.py b/docutils/docutils/utils/math/math2html.py
index 36b7efe6d..44d9c20fa 100755
--- a/docutils/docutils/utils/math/math2html.py
+++ b/docutils/docutils/utils/math/math2html.py
@@ -175,16 +175,16 @@ class FormulaConfig(object):
                  u'∥': [u'∥',],
                 }
 
-  bigsymbols = {u'∑': [u'⎲', u'⎳',], # ⎲ ⌠ ┌
-                u'∫': [u'⌠', u'⌡',], # ⎳ ⎮ │
-                u'√': [u'┌', u'⎷',], #   ⌡ ⎷
+  bigsymbols = {# u'∑': [u'⎲', u'⎳',], # ⎲ ⌠ ┌
+                # u'∫': [u'⌠', u'⌡',], # ⎳ ⎮ │
+                # u'√': [u'┌', u'⎷',], #   ⌡ ⎷
                }
 
   bracketcommands = {
-      u'\\left': u'span class="symbol"',
+      u'\\left': u'span class="bigdelimiter size2"',
       u'\\left.': u'<span class="leftdot"></span>',
-      u'\\middle': u'span class="symbol"',
-      u'\\right': u'span class="symbol"',
+      u'\\middle': u'span class="bigdelimiter size2"',
+      u'\\right': u'span class="bigdelimiter size2"',
       u'\\right.': u'<span class="rightdot"></span>',
       }
 
@@ -206,6 +206,8 @@ class FormulaConfig(object):
 
   commands = {
       '\\\\': u'<br/>',
+      '\\\n': u' ', # escaped whitespace
+      '\\\t': u' ', # escaped whitespace
       '\\colon': u': ',
       '\\copyright': u'©',
       '\\dotminus': u'∸',
@@ -382,7 +384,7 @@ class FormulaConfig(object):
       u'\\addcontentsline': [u'{$p!}{$q!}{$r!}', u'f0{}', u'ignored',],
       u'\\addtocontents': [u'{$p!}{$q!}', u'f0{}', u'ignored',],
       u'\\backmatter': [u'', u'f0{}', u'ignored',],
-      u'\\binom': [u'{$1}{$2}', u'f2{(}f0{f1{$1}f1{$2}}f2{)}', u'span class="binom"', u'span class="binomstack"', u'span class="bigsymbol"',],
+      u'\\binom': [u'{$1}{$2}', u'f2{(}f0{f1{$1}f1{$2}}f2{)}', u'span class="binom"', u'span class="binomstack"', u'span class="bigdelimiter size2"',],
       u'\\boxed': [u'{$1}', u'f0{$1}', u'span class="boxed"',],
       u'\\cfrac': [u'[$p!]{$1}{$2}', u'f0{f3{(}f1{$1}f3{)/(}f2{$2}f3{)}}', u'span class="fullfraction"', u'span class="numerator align-$p"', u'span class="denominator"', u'span class="ignored"',],
       u'\\color': [u'{$p!}{$1}', u'f0{$1}', u'span style="color: $p;"',],
@@ -437,31 +439,30 @@ class FormulaConfig(object):
   limitcommands = {
       '\\biginterleave': u'⫼',
       '\\inf': u'inf',
-      '\\intop': u'∫', # large operator via pieces from bigsymbols
       '\\lim': u'lim',
       '\\max': u'max',
       '\\min': u'min',
-      '\\sum': u'∑',   # large operator via pieces from bigsymbols
       '\\sup': u'sup',
       '\\ointop':    u'<span class="bigoperator">∮</span>',
-      '\\bigcap':    u'<span class="bigoperator">∩</span>',
-      '\\bigcup':    u'<span class="bigoperator">∪</span>',
-      '\\bigodot':   u'<span class="bigoperator">⊙</span>',
-      '\\bigoplus':  u'<span class="bigoperator">⊕</span>',
-      '\\bigotimes': u'<span class="bigoperator">⊗</span>',
+      '\\bigcap':    u'<span class="bigoperator">⋂</span>',
+      '\\bigcup':    u'<span class="bigoperator">⋃</span>',
+      '\\bigodot':   u'<span class="bigoperator">⨀</span>',
+      '\\bigoplus':  u'<span class="bigoperator">⨁</span>',
+      '\\bigotimes': u'<span class="bigoperator">⨂</span>',
       '\\bigsqcap':  u'<span class="bigoperator">⨅</span>',
-      '\\bigsqcup':  u'<span class="bigoperator">⊔</span>',
-      '\\biguplus':  u'<span class="bigoperator">⊎</span>',
-      '\\bigvee':    u'<span class="bigoperator">∨</span>',
-      '\\bigwedge':  u'<span class="bigoperator">∧</span>',
+      '\\bigsqcup':  u'<span class="bigoperator">⨆</span>',
+      '\\biguplus':  u'<span class="bigoperator">⨄</span>',
+      '\\bigvee':    u'<span class="bigoperator">⋁</span>',
+      '\\bigwedge':  u'<span class="bigoperator">⋀</span>',
       '\\coprod':    u'<span class="bigoperator">∐</span>',
+      '\\intop':     u'<span class="bigoperator">∫</span>',
       '\\prod':      u'<span class="bigoperator">∏</span>',
+      '\\sum':       u'<span class="bigoperator">∑</span>',
       '\\varprod':   u'<span class="bigoperator">⨉</span>',
       '\\zcmp': u'⨟', '\\zhide': u'⧹', '\\zpipe': u'⨠', '\\zproject': u'⨡',
       # integrals have limits in index position with LaTeX default settings
       # TODO: move to commands?
-      '\\int': u'∫',
-      '\\smallint': u'∫',
+      '\\int': u'<span class="bigoperator">∫</span>',
       '\\fint': u'<span class="bigoperator">⨏</span>',
       '\\iiiint': u'<span class="bigoperator">⨌</span>',
       '\\sqint': u'<span class="bigoperator">⨖</span>',
@@ -475,20 +476,20 @@ class FormulaConfig(object):
       }
 
   onefunctions = {
-      '\\Big': 'span class="bigsymbol"',
-      '\\Bigl': 'span class="bigsymbol"',
-      '\\Bigr': 'span class="bigsymbol"',
-      '\\Bigg': 'span class="hugesymbol"',
-      '\\Biggl': 'span class="hugesymbol"',
-      '\\Biggr': 'span class="hugesymbol"',
+      '\\big': 'span class="bigdelimiter size1"',
+      '\\bigl': 'span class="bigdelimiter size1"',
+      '\\bigr': 'span class="bigdelimiter size1"',
+      '\\Big': 'span class="bigdelimiter size2"',
+      '\\Bigl': 'span class="bigdelimiter size2"',
+      '\\Bigr': 'span class="bigdelimiter size2"',
+      '\\bigg': 'span class="bigdelimiter size3"',
+      '\\biggl': 'span class="bigdelimiter size3"',
+      '\\biggr': 'span class="bigdelimiter size3"',
+      '\\Bigg': 'span class="bigdelimiter size4"',
+      '\\Biggl': 'span class="bigdelimiter size4"',
+      '\\Biggr': 'span class="bigdelimiter size4"',
       # '\\bar': 'span class="bar"',
       '\\begin{array}': 'span class="arraydef"',
-      '\\big': 'span class="symbol"', 
-      '\\bigl': 'span class="symbol"',
-      '\\bigr': 'span class="symbol"',
-      '\\bigg': 'span class="largesymbol"',
-      '\\biggl': 'span class="largesymbol"',
-      '\\biggr': 'span class="largesymbol"',
       '\\centering': 'span class="align-center"',
       '\\ensuremath': 'span class="ensuremath"',
       '\\hphantom': 'span class="phantom"',
@@ -2489,7 +2490,7 @@ class BigBracket(BigSymbol):
     "Return the bracket as a single sign."
     if self.original == '.':
       return [TaggedBit().constant('', 'span class="emptydot"')]
-    return [TaggedBit().constant(self.original, 'span class="symbol"')]
+    return [TaggedBit().constant(self.original, 'span class="bigdelimiter size2"')]
 
 
 class FormulaEquation(CommandBit):
diff --git a/docutils/docutils/writers/html5_polyglot/math.css b/docutils/docutils/writers/html5_polyglot/math.css
index 47c6aeae5..7b7207264 100644
--- a/docutils/docutils/writers/html5_polyglot/math.css
+++ b/docutils/docutils/writers/html5_polyglot/math.css
@@ -25,7 +25,8 @@
 /* Formulas */
 .formula {
 	text-align: center;
-	font-family: "Droid Serif", "DejaVu Serif", STIX, serif;
+	font-family: "DejaVu Serif", STIX, serif;
+	/* "DejaVu Math TeX Gyre", (brace pieces don't fit) */
 	margin: 1.2em 0;
 	line-height: 1.4;
 }
@@ -126,14 +127,6 @@ span.radical {
 	vertical-align: middle;
 }
 
-/* div.formula span.sqrt span.radical:before { */
-/*         writing-mode: vertical-lr;	       */
-/*  	text-orientation: upright;	       */
-/*         content: "┌│⎷";		       */
-/* }					       */
-/* or use "transform" property				      */
-/* https://developer.mozilla.org/en-US/docs/Web/CSS/transform */
-
 span.root {
 	display: inline-block;
 	border-top: thin solid;
@@ -145,16 +138,32 @@ span.symbol {
 	line-height: 125%;
 	font-size: 125%;
 }
-/* TODO: use transform matrix to stretch fences */
-span.bigsymbol, div.formula span.bigoperator {
-	line-height: 150%;
+div.formula .bigoperator,
+.displaystyle .bigoperator,
+.displaystyle .bigoperator {
+        line-height: 150%;
 	font-size: 150%;
 }
-span.largesymbol {
-	font-size: 175%;
+span.fraction .bigoperator,
+span.scriptstyle .bigoperator{
+	line-height: inherit;
+	font-size: inherit;
+}
+span.bigdelimiter {
+	display: inline-block;
+	vertical-align: text-bottom;
+}
+span.bigdelimiter.size1 {
+	transform: scale(1, 1.2);
 }
-span.hugesymbol {
-	font-size: 200%;
+span.bigdelimiter.size2 {
+	transform: scale(1, 1.62);
+}
+span.bigdelimiter.size3 {
+	transform: scale(1, 2.05);
+}
+span.bigdelimiter.size4 {
+	transform: scale(1, 2.47);
 }
 /* vertically stacked sub and superscript */
 span.scripts {
@@ -174,7 +183,7 @@ span.limits {
 }
 .limit {
 	display: table-row;
-	line-height: 99%;
+/* 	line-height: 99%;    */
 }
 sup.limit, sub.limit {
 	line-height: 100%;
@@ -211,9 +220,12 @@ span.arrayrow, span.binomrow {
 span.arraycell, span.bracket, span.case, span.binomcell, span.environmentcell {
 	display: table-cell;
 	padding: 0ex 0.2ex;
-	line-height: 99%;
+	line-height: 1; /* 99%; */
 	border: 0ex;
 }
+.environment.align > .arrayrow > .arraycell.align-l {
+	padding-right: 2em;
+}
 /*
 * CSS file for LaTeX formulas, extra stuff:
 * binomials, vertical braces, stackrel, fonts and colors.
diff --git a/docutils/test/functional/expected/math_output_html.html b/docutils/test/functional/expected/math_output_html.html
index 2f58a359c..ca203bc8c 100644
--- a/docutils/test/functional/expected/math_output_html.html
+++ b/docutils/test/functional/expected/math_output_html.html
@@ -59,10 +59,10 @@ See <a class="reference internal" href="#eq-m">eq:M</a> and <a class="reference
 <p>More than one display math block can be put in one math directive.
 For example, the following sum and integral with limits:</p>
 <div class="formula">
-<span class="limits"><sup class="limit">1</sup><span class="limit">⌠</span><span class="limit">⌡</span><sub class="limit">0</sub></span><i>x</i><sup><i>n</i></sup><i>dx</i> = <span class="fraction"><span class="ignored">(</span><span class="numerator">1</span><span class="ignored">)/(</span><span class="denominator"><i>n</i> + 1</span><span class="ignored">)</span></span>
+<span class="limits"><sup class="limit">1</sup><span class="limit"><span class="bigoperator">∫</span></span><sub class="limit">0</sub></span><i>x</i><sup><i>n</i></sup><i>dx</i> = <span class="fraction"><span class="ignored">(</span><span class="numerator">1</span><span class="ignored">)/(</span><span class="denominator"><i>n</i> + 1</span><span class="ignored">)</span></span>
 </div>
 <div class="formula">
-<span class="limits"><sup class="limit"><i>m</i></sup><span class="limit">⎲</span><span class="limit">⎳</span><sub class="limit"><i>n</i> = 1</sub></span><i>n</i> = <span class="fraction"><span class="ignored">(</span><span class="numerator"><i>m</i>(<i>m</i> + 1)</span><span class="ignored">)/(</span><span class="denominator">2</span><span class="ignored">)</span></span>
+<span class="limits"><sup class="limit"><i>m</i></sup><span class="limit"><span class="bigoperator">∑</span></span><sub class="limit"><i>n</i> = 1</sub></span><i>n</i> = <span class="fraction"><span class="ignored">(</span><span class="numerator"><i>m</i>(<i>m</i> + 1)</span><span class="ignored">)/(</span><span class="denominator">2</span><span class="ignored">)</span></span>
 </div>
 <p>LaTeX-supported Unicode math symbols can be used in math roles and
 directives:</p>
@@ -105,7 +105,7 @@ physical system changes in time.</p>
 \widehat{xxx} -->
 <p>Modulation Transfer Function:</p>
 <div class="formula">
-<span class="text">MTF</span> = <span class="array"><span class="arrayrow"><span class="bracket align-left">|</span></span><span class="arrayrow"><span class="bracket align-left">|</span></span></span><span class="fraction"><span class="ignored">(</span><span class="numerator">ℱ{<i>s</i>(<i>x</i>)}</span><span class="ignored">)/(</span><span class="denominator">ℱ{<i>s</i>(<i>x</i>)}|<sub><i>ω</i><sub><i>x</i></sub> = 0</sub></span><span class="ignored">)</span></span><span class="array"><span class="arrayrow"><span class="bracket align-right">|</span></span><span class="arrayrow"><span class="bracket align-right">|</span></span></span> = <span class="mathrm"> abs</span><span class="array"><span class="arrayrow"><span class="bracket align-left">⎛</span></span><span class="arrayrow"><span class="bracket align-left">⎝</span></span></span><span class="fraction"><span class="ignored">(</span><span class="numerator"><span class="limits"><span class="limit">⌠</span><span class="limit">⌡</span></span><span class="scripts"><sup class="script">∞</sup><sub class="script"> − ∞</sub></span><i>s</i>(<i>x</i>)<span class="mathrm">e</span><sup><span class="mathrm">i</span><i>ω</i><sub><i>x</i></sub><i>x</i></sup><span class="mathrm">d</span><i>x</i></span><span class="ignored">)/(</span><span class="denominator"><span class="limits"><span class="limit">⌠</span><span class="limit">⌡</span></span><span class="scripts"><sup class="script">∞</sup><sub class="script"> − ∞</sub></span><i>s</i>(<i>x</i>)<span class="mathrm">d</span><i>x</i></span><span class="ignored">)</span></span><span class="array"><span class="arrayrow"><span class="bracket align-right">⎞</span></span><span class="arrayrow"><span class="bracket align-right">⎠</span></span></span>.
+<span class="text">MTF</span> = <span class="array"><span class="arrayrow"><span class="bracket align-left">|</span></span><span class="arrayrow"><span class="bracket align-left">|</span></span></span><span class="fraction"><span class="ignored">(</span><span class="numerator">ℱ{<i>s</i>(<i>x</i>)}</span><span class="ignored">)/(</span><span class="denominator">ℱ{<i>s</i>(<i>x</i>)}|<sub><i>ω</i><sub><i>x</i></sub> = 0</sub></span><span class="ignored">)</span></span><span class="array"><span class="arrayrow"><span class="bracket align-right">|</span></span><span class="arrayrow"><span class="bracket align-right">|</span></span></span> = <span class="mathrm"> abs</span><span class="array"><span class="arrayrow"><span class="bracket align-left">⎛</span></span><span class="arrayrow"><span class="bracket align-left">⎝</span></span></span><span class="fraction"><span class="ignored">(</span><span class="numerator"><span class="limits"><span class="limit"><span class="bigoperator">∫</span></span></span><span class="scripts"><sup class="script">∞</sup><sub class="script"> − ∞</sub></span><i>s</i>(<i>x</i>)<span class="mathrm">e</span><sup><span class="mathrm">i</span><i>ω</i><sub><i>x</i></sub><i>x</i></sup><span class="mathrm">d</span><i>x</i></span><span class="ignored">)/(</span><span class="denominator"><span class="limits"><span class="limit"><span class="bigoperator">∫</span></span></span><span class="scripts"><sup class="script">∞</sup><sub class="script"> − ∞</sub></span><i>s</i>(<i>x</i>)<span class="mathrm">d</span><i>x</i></span><span class="ignored">)</span></span><span class="array"><span class="arrayrow"><span class="bracket align-right">⎞</span></span><span class="arrayrow"><span class="bracket align-right">⎠</span></span></span>.
 </div>
 <p>Math split over two lines: If a double backslash is detected outside a
 <tt class="docutils literal"><span class="pre">\begin{...}</span> <span class="pre">\end{...}</span></tt> pair, the math code is wrapped in an <a class="reference external" href="ftp://ftp.ams.org/ams/doc/amsmath/short-math-guide.pdf">AMSmath</a>
@@ -134,7 +134,7 @@ physical system changes in time.</p>
 
 </span>
 <span class="arraycell align-l">
- = <span class="limits"><span class="limit">⌠</span><span class="limit">⌡</span></span><i>s</i><sub><span class="mathrm">in</span></sub>(<i>x</i>’)<i>s</i><sub><i>δ</i></sub>(<i>x</i> − <i>x</i>’)<span class="mathrm">d</span><i>x</i>’
+ = <span class="limits"><span class="limit"><span class="bigoperator">∫</span></span></span><i>s</i><sub><span class="mathrm">in</span></sub>(<i>x</i>’)<i>s</i><sub><i>δ</i></sub>(<i>x</i> − <i>x</i>’)<span class="mathrm">d</span><i>x</i>’
 </span>
 
 </span>