some support for \atop

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@2542 a592a061-630c-0410-9148-cb99ea01b6c8

src/mathed/math_cursor.C

@@ -1188,7 +1188,7 @@ void MathCursor::interpret(string const & s)
 		return;
 	}
 
-	if (s == "\\over" || s == "\\choose") {
+	if (s == "\\over" || s == "\\choose" || s == "\\atop") {
 		MathArray ar = array();
 		MathInset * p = createMathInset(in_word_set(s.substr(1)));
 		p->cell(0).swap(array());

src/mathed/math_factory.C

@@ -39,6 +39,8 @@ MathInset * createMathInset(latexkeys const * l)
 		case LM_TK_OVER:
 		case LM_TK_FRAC:
 			return new MathFracInset;
+		case LM_TK_ATOP:
+			return new MathFracInset(true);
 		case LM_TK_NOT:
 			return new MathNotInset;
 		case LM_TK_SQRT:

src/mathed/math_fracinset.C

@@ -8,7 +8,8 @@
 #include "support/LOstream.h"
 
 
-MathFracInset::MathFracInset()
+MathFracInset::MathFracInset(bool atop)
+	: atop_(atop)
 {}
 
 
@@ -36,23 +37,35 @@ void MathFracInset::draw(Painter & pain, int x, int y) const
 	int m = x + width() / 2;
 	xcell(0).draw(pain, m - xcell(0).width() / 2, y - xcell(0).descent() - 3 - 5);
 	xcell(1).draw(pain, m - xcell(1).width() / 2, y + xcell(1).ascent()  + 3 - 5);
-	pain.line(x + 2, y - 5, x + width() - 4, y - 5, LColor::mathline);
+	if (!atop_)
+		pain.line(x + 2, y - 5, x + width() - 4, y - 5, LColor::mathline);
 }
 
 
 void MathFracInset::write(std::ostream & os, bool fragile) const
 {
-	os << "\\frac{";
-	cell(0).write(os, fragile);
-	os << "}{";
-	cell(1).write(os, fragile);
-	os << '}';
+	if (atop_) {
+		os << "{";
+		cell(0).write(os, fragile);
+		os << "\\atop ";
+		cell(1).write(os, fragile);
+		os << '}';
+	} else {
+		os << "\\frac{";
+		cell(0).write(os, fragile);
+		os << "}{";
+		cell(1).write(os, fragile);
+		os << '}';
+	}
 }
 
 
 void MathFracInset::writeNormal(std::ostream & os) const
 {
-	os << "[frac ";
+	if (atop_) 
+		os << "[atop ";
+	else
+		os << "[frac ";
 	cell(0).writeNormal(os);
 	os << " ";
 	cell(1).writeNormal(os);

src/mathed/math_fracinset.h

@@ -14,7 +14,7 @@
 class MathFracInset : public MathFracbaseInset {
 public:
 	///
-	MathFracInset();
+	explicit MathFracInset(bool atop = false);
 	///
 	MathInset * clone() const;
 	///
@@ -25,6 +25,12 @@ public:
 	void metrics(MathStyles st) const;
 	///
 	void draw(Painter &, int x, int y) const;
+public:
+	///
+	char const name() const;
+
+	///
+	const bool atop_;
 };
 
 #endif

src/mathed/math_hash.C

@@ -67,6 +67,7 @@ latexkeys wordlist[] =
 	{"arctan",  LM_TK_FUNC, 0, LMB_NONE},
 	{"arg",  LM_TK_FUNC, 0, LMB_NONE},
 	{"asymp",  LM_TK_NOGLYPH, 0, LMB_RELATION},
+	{"atop",  LM_TK_ATOP, 0, LMB_NONE},
 	{"backslash",  LM_TK_SPECIAL, '\\', LMB_NONE},
 	{"bar",  LM_TK_DECORATION, LM_bar, LMB_NONE},
 	{"begin",  LM_TK_BEGIN, 0, LMB_NONE},

src/mathed/math_parser.C

@@ -820,7 +820,7 @@ void Parser::parse_into(MathArray & array, unsigned flags)
 			//curr_label_ = getArg('{', '}');
 		}
 
-		else if (t.cs() == "choose" || t.cs() == "over") {
+		else if (t.cs() == "choose" || t.cs() == "over" || t.cs() == "atop") {
 			limits = 0;
 			MathInset * p = createMathInset(t.cs());
 			p->cell(0).swap(array);

src/mathed/math_parser.h

@@ -43,6 +43,8 @@ enum MathTokenEnum
 	///
 	LM_TK_BINOM,
 	///
+	LM_TK_ATOP,
+	///
 	LM_TK_OVER,
 	///
 	LM_TK_FRAC,