From a44e7aa9156049a682c7496ea54ae665be91630b Mon Sep 17 00:00:00 2001
From: Guillaume Munch <gm@lyx.org>
Date: Tue, 20 Dec 2016 00:15:59 +0100
Subject: [PATCH] Factor code for math axis height

---
 src/mathed/InsetMathFrac.cpp | 16 ++++------------
 src/mathed/MathSupport.cpp   |  7 +++++++
 src/mathed/MathSupport.h     |  3 +++
 3 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/src/mathed/InsetMathFrac.cpp b/src/mathed/InsetMathFrac.cpp
index ad999a221d..ada6476c50 100644
--- a/src/mathed/InsetMathFrac.cpp
+++ b/src/mathed/InsetMathFrac.cpp
@@ -154,14 +154,6 @@ MathClass InsetMathFrac::mathClass() const
 
 namespace {
 
-// align frac to minus character
-int dy_for_frac(MetricsBase & mb)
-{
-	Changer dummy = mb.changeFontSet("mathnormal");
-	return theFontMetrics(mb.font).ascent('-') - 1;
-}
-
-
 // align the top of M in the cell with the top of M in the surrounding font
 int dy_for_nicefrac(MetricsBase & mb)
 {
@@ -249,7 +241,7 @@ void InsetMathFrac::metrics(MetricsInfo & mi, Dimension & dim) const
 	case TFRAC:
 	case OVER:
 	case ATOP: {
-		int const dy = dy_for_frac(mi.base);
+		int const dy = axis_height(mi.base);
 		Changer dummy =
 			// \tfrac is always in text size
 			(kind_ == TFRAC) ? mi.base.font.changeStyle(LM_ST_SCRIPT) :
@@ -332,7 +324,7 @@ void InsetMathFrac::draw(PainterInfo & pi, int x, int y) const
 	case TFRAC:
 	case OVER:
 	case ATOP: {
-		int const dy = dy_for_frac(pi.base);
+		int const dy = axis_height(pi.base);
 		Changer dummy =
 			// \tfrac is always in text size
 			(kind_ == TFRAC) ? pi.base.font.changeStyle(LM_ST_SCRIPT) :
@@ -658,7 +650,7 @@ void InsetMathBinom::metrics(MetricsInfo & mi, Dimension & dim) const
 {
 	Changer dummy2 = mi.base.changeEnsureMath();
 	Dimension dim0, dim1;
-	int const dy = dy_for_frac(mi.base);
+	int const dy = axis_height(mi.base);
 	Changer dummy =
 		(kind_ == DBINOM) ? mi.base.font.changeStyle(LM_ST_DISPLAY) :
 		(kind_ == TBINOM) ? mi.base.font.changeStyle(LM_ST_SCRIPT) :
@@ -678,7 +670,7 @@ void InsetMathBinom::draw(PainterInfo & pi, int x, int y) const
 	Dimension const dim = dimension(*pi.base.bv);
 	Dimension const & dim0 = cell(0).dimension(*pi.base.bv);
 	Dimension const & dim1 = cell(1).dimension(*pi.base.bv);
-	int const dy = dy_for_frac(pi.base);
+	int const dy = axis_height(pi.base);
 	// define the binom brackets
 	docstring const bra = kind_ == BRACE ? from_ascii("{") :
 		kind_ == BRACK ? from_ascii("[") : from_ascii("(");
diff --git a/src/mathed/MathSupport.cpp b/src/mathed/MathSupport.cpp
index 222807bba4..5df8a0673e 100644
--- a/src/mathed/MathSupport.cpp
+++ b/src/mathed/MathSupport.cpp
@@ -985,4 +985,11 @@ docstring asString(MathAtom const & at)
 }
 
 
+int axis_height(MetricsBase & mb)
+{
+	Changer dummy = mb.changeFontSet("mathnormal");
+	return theFontMetrics(mb.font).ascent('-') - 1;
+}
+
+
 } // namespace lyx
diff --git a/src/mathed/MathSupport.h b/src/mathed/MathSupport.h
index 87f824dc16..2b3e48f68f 100644
--- a/src/mathed/MathSupport.h
+++ b/src/mathed/MathSupport.h
@@ -81,6 +81,9 @@ docstring asString(MathAtom const &);
 // converts string to single cell
 void asArray(docstring const &, MathData &, Parse::flags f = Parse::NORMAL);
 
+// simulate axis height (font dimension sigma 22)
+int axis_height(MetricsBase & mb);
+
 } // namespace lyx
 
 #endif
-- 
2.39.5