Rely on Qt to handle small caps text

This has the advantage of simplifying our code and to produce the
correct output: the small capitals should have the exact same width as
the lower case letters.

The slanted fonts are also translated to oblique on Qt side, but this
does not seems to have an effect in my testing. It may be that proper
oblique fonts need to be installed.

src/frontends/qt4/GuiFontLoader.cpp

@@ -304,8 +304,13 @@ GuiFontInfo::GuiFontInfo(FontInfo const & f)
 
 	switch (f.realShape()) {
 		case ITALIC_SHAPE:
+			font.setStyle(QFont::StyleItalic);
+			break;
 		case SLANTED_SHAPE:
-			font.setItalic(true);
+			font.setStyle(QFont::StyleOblique);
+			break;
+		case SMALLCAPS_SHAPE:
+			font.setCapitalization(QFont::SmallCaps);
 			break;
 		default:
 			break;
@@ -327,19 +332,7 @@ GuiFontInfo::GuiFontInfo(FontInfo const & f)
 
 	LYXERR(Debug::FONT, "The font has size: " << font.pointSizeF());
 
-	if (f.realShape() != SMALLCAPS_SHAPE) {
-		metrics = GuiFontMetrics(font);
-	} else {
-		// handle small caps ourselves ...
-		FontInfo smallfont = f;
-		smallfont.decSize().decSize().setShape(UP_SHAPE);
-		QFont font2(font);
-		font2.setKerning(false);
-		font2.setPointSizeF(convert<double>(lyxrc.font_sizes[smallfont.size()])
-			       * lyxrc.zoom / 100.0);
-
-		metrics = GuiFontMetrics(font, font2);
-	}
+	metrics = GuiFontMetrics(font);
 }
 
 

src/frontends/qt4/GuiFontMetrics.cpp

@@ -49,14 +49,7 @@ inline QChar const ucs4_to_qchar(char_type const ucs4)
 } // anon namespace
 
 
-GuiFontMetrics::GuiFontMetrics(QFont const & font)
-: metrics_(font, 0), smallcaps_metrics_(font), smallcaps_shape_(false)
-{
-}
-
-
-GuiFontMetrics::GuiFontMetrics(QFont const & font, QFont const & smallcaps_font)
-: metrics_(font, 0), smallcaps_metrics_(smallcaps_font), smallcaps_shape_(true)
+GuiFontMetrics::GuiFontMetrics(QFont const & font) : metrics_(font, 0)
 {
 }
 
@@ -115,27 +108,6 @@ int GuiFontMetrics::rbearing(char_type c) const
 }
 
 
-int GuiFontMetrics::smallcapsWidth(char_type c) const
-{
-	// FIXME: Optimisation probably needed: we don't use the width cache.
-	if (is_utf16(c)) {
-		QChar const qc = ucs4_to_qchar(c);
-		QChar const uc = qc.toUpper();
-		if (qc != uc)
-			return smallcaps_metrics_.width(uc);
-		else
-			return metrics_.width(qc);
-	} else {
-		QString const s = toqstr(docstring(1, c));
-		QString const us = s.toUpper();
-		if (s != us)
-			return smallcaps_metrics_.width(us);
-		else
-			return metrics_.width(s);
-	}
-}
-
-
 int GuiFontMetrics::width(docstring const & s) const
 {
 	size_t ls = s.size();
@@ -145,10 +117,7 @@ int GuiFontMetrics::width(docstring const & s) const
 		/**
 		if isSurrogateBase(s[i]) {
 			docstring c = s[i];
-			if (smallcaps_shape_)
-				w += metrics_.width(toqstr(c + s[i + 1]));
-			else
-				w += smallcaps_metrics_.width(toqstr(c + s[i + 1]));
+			w += metrics_.width(toqstr(c + s[i + 1]));
 			++i;
 		}
 		else
@@ -230,9 +199,6 @@ GuiFontMetrics::AscendDescend const GuiFontMetrics::fillMetricsCache(
 
 int GuiFontMetrics::width(char_type c) const
 {
-	if (smallcaps_shape_)
-		return smallcapsWidth(c);
-
 	int value = width_cache_.value(c, outOfLimitMetric);
 	if (value != outOfLimitMetric)
 		return value;

src/frontends/qt4/GuiFontMetrics.h

@@ -26,7 +26,6 @@ class GuiFontMetrics : public FontMetrics
 {
 public:
 	GuiFontMetrics(QFont const & font);
-	GuiFontMetrics(QFont const & font, QFont const & smallcaps_font);
 
 	virtual ~GuiFontMetrics() {}
 
@@ -54,13 +53,8 @@ public:
 	int width(QString const & str) const;
 
 private:
-	int smallcapsWidth(char_type c) const;
-
 	/// Metrics on the font
 	QFontMetrics metrics_;
-	QFontMetrics smallcaps_metrics_;
-
-	bool smallcaps_shape_;
 
 	/// Cache of char widths
 	mutable QHash<char_type, int> width_cache_;

src/frontends/qt4/GuiPainter.cpp

@@ -276,33 +276,6 @@ int GuiPainter::text(int x, int y, char_type c, FontInfo const & f)
 }
 
 
-int GuiPainter::smallCapsText(int x, int y,
-	QString const & s, FontInfo const & f)
-{
-	FontInfo smallfont(f);
-	smallfont.decSize().decSize().setShape(UP_SHAPE);
-
-	QFont const & qfont = getFont(f);
-	QFont const & qsmallfont = getFont(smallfont);
-
-	setQPainterPen(computeColor(f.realColor()));
-	int textwidth = 0;
-	size_t const ls = s.length();
-	for (unsigned int i = 0; i < ls; ++i) {
-		QChar const c = s[i].toUpper();
-		if (c != s.at(i)) {
-			setFont(qsmallfont);
-		} else {
-			setFont(qfont);
-		}
-		if (isDrawingEnabled())
-			drawText(x + textwidth, y, c);
-		textwidth += fontMetrics().width(c);
-	}
-	return textwidth;
-}
-
-
 int GuiPainter::text(int x, int y, docstring const & s,
 		FontInfo const & f)
 {
@@ -334,12 +307,6 @@ int GuiPainter::text(int x, int y, docstring const & s,
 
 	int textwidth;
 
-	if (f.realShape() == SMALLCAPS_SHAPE) {
-		textwidth = smallCapsText(x, y, str, f);
-		textDecoration(f, x, y, textwidth);
-		return textwidth;
-	}
-
 	// Here we use the font width cache instead of
 	//   textwidth = fontMetrics().width(str);
 	// because the above is awfully expensive on MacOSX

src/frontends/qt4/GuiPainter.h

@@ -144,13 +144,6 @@ private:
 	/// draw a bevelled button border
 	void buttonFrame(int x, int y, int w, int h);
 
-	/// draw small caps text
-	/**
-	\return width of the drawn text.
-	*/
-	int smallCapsText(int x, int y,
-		QString const & str, FontInfo const & f);
-
 	/// set pen parameters
 	void setQPainterPen(QColor const & col,
 		line_style ls = line_solid, float lw = thin_line);