From: Jean-Marc Lasgouttes <lasgouttes@lyx.org>
Date: Mon, 9 Apr 2018 10:18:24 +0000 (+0200)
Subject: Set a minimal height for math rows
X-Git-Tag: 2.3.1~86
X-Git-Url: https://git.lyx.org/gitweb/?a=commitdiff_plain;h=f33d0789f6360e0b196e738d025360c2ef793b42;p=features.git

Set a minimal height for math rows

The value used here is the x height. It would be nice to see what the
TeXbook really says.

This makes a big difference with \tilde{.}, for example.

(cherry picked from commit 6df8c42e59f7dbe00d585525d1ce7e91a42411ca)
---

diff --git a/src/mathed/MathRow.cpp b/src/mathed/MathRow.cpp
index 345962096f..561081556e 100644
--- a/src/mathed/MathRow.cpp
+++ b/src/mathed/MathRow.cpp
@@ -236,7 +236,10 @@ int MathRow::after(int i) const
 
 void MathRow::metrics(MetricsInfo & mi, Dimension & dim)
 {
-	dim.asc = 0;
+	frontend::FontMetrics const & fm = theFontMetrics(mi.base.font);
+	// FIXME: this is the minimal ascent seen empirically, check
+	// what the TeXbook says.
+	dim.asc = fm.ascent('x');
 	dim.wid = 0;
 	// In order to compute the dimension of macros and their
 	// arguments, it is necessary to keep track of them.
@@ -284,7 +287,7 @@ void MathRow::metrics(MetricsInfo & mi, Dimension & dim)
 			}
 			break;
 		case BOX:
-			d = theFontMetrics(mi.base.font).dimension('I');
+			d = fm.dimension('I');
 			if (e.color != Color_none) {
 				// allow for one pixel before/after the box.
 				d.wid += e.before + e.after + 2;