From: Vincent van Ravesteijn <vfr@lyx.org>
Date: Tue, 6 Jan 2015 17:48:19 +0000 (+0100)
Subject: str_metrics: Prevent clipping of chars with negative bearing
X-Git-Tag: 2.2.0alpha1~1382
X-Git-Url: https://git.lyx.org/gitweb/?a=commitdiff_plain;h=c313b1c8eb01c85775e62a8675fa569d2c2aac2c;p=features.git

str_metrics: Prevent clipping of chars with negative bearing

This happens when part of the word is selected.

To reproduce:
1. Start a new document
2. Type "af"
3. Select 'a'
4. Observe that the right part of the 'f' is clipped away.

This patch uses QRegion to set a clip region that is everything except
the part that is drawn in another color.

Fixes: #9223.
---

diff --git a/src/frontends/qt4/GuiPainter.cpp b/src/frontends/qt4/GuiPainter.cpp
index 5730819a02..95ab52a98f 100644
--- a/src/frontends/qt4/GuiPainter.cpp
+++ b/src/frontends/qt4/GuiPainter.cpp
@@ -465,15 +465,16 @@ int GuiPainter::text(int x, int y, docstring const & str, Font const & f,
 	// First the part in other color
 	Color const orig = fi.realColor();
 	fi.setPaintColor(other);
-	setClipRect(QRect(x + xmin, y - ascent, xmax - xmin, height));
+	QRegion const clip(x + xmin, y - ascent, xmax - xmin, height);
+	setClipRegion(clip);
 	int const textwidth = text(x, y, str, fi, rtl);
 
 	// Then the part in normal color
-	// Note that in Qt5, it is not possible to use Qt::UniteClip
+	// Note that in Qt5, it is not possible to use Qt::UniteClip,
+	// therefore QRegion is used.
 	fi.setPaintColor(orig);
-	setClipRect(QRect(x, y - ascent, xmin, height));
-	text(x, y, str, fi, rtl);
-	setClipRect(QRect(x + xmax, y - ascent, textwidth - xmax, height));
+	QRegion region(viewport());
+	setClipRegion(region - clip);
 	text(x, y, str, fi, rtl);
 	setClipping(false);