Add support for Chinese translations of Chinese cultures

This leaves out " Added" suffixes, which makes corresponding names
untranslated yet.
Also, this doesn't handle Chinese cultures in non-Chinese locales.

src/core/StelTranslator.cpp

@@ -28,6 +28,37 @@
 #include <QDir>
 #include <QTranslator>
 
+namespace
+{
+int parseRomanNumeral(const QStringView& roman)
+{
+	const auto romanLat = roman.toLatin1();
+	int v = 0;
+	const char* p = romanLat.data();
+
+	/**/ if (strncmp(p, "XC",   2) == 0) { v += 90; p += 2; }
+	else if (strncmp(p, "LXXX", 4) == 0) { v += 80; p += 4; }
+	else if (strncmp(p, "LXX",  3) == 0) { v += 70; p += 3; }
+	else if (strncmp(p, "LX",   2) == 0) { v += 60; p += 2; }
+	else if (strncmp(p, "L",    1) == 0) { v += 50; p += 1; }
+	else if (strncmp(p, "XL",   2) == 0) { v += 40; p += 2; }
+	else if (strncmp(p, "XXX",  3) == 0) { v += 30; p += 3; }
+	else if (strncmp(p, "XX",   2) == 0) { v += 20; p += 2; }
+	else if (strncmp(p, "X",    1) == 0) { v += 10; p += 1; }
+
+	/**/ if (strncmp(p, "IX",   2) == 0) { v += 9;  p += 2; }
+	else if (strncmp(p, "VIII", 4) == 0) { v += 8;  p += 4; }
+	else if (strncmp(p, "VII",  3) == 0) { v += 7;  p += 3; }
+	else if (strncmp(p, "VI",   2) == 0) { v += 6;  p += 2; }
+	else if (strncmp(p, "V",    1) == 0) { v += 5;  p += 1; }
+	else if (strncmp(p, "IV",   2) == 0) { v += 4;  p += 2; }
+	else if (strncmp(p, "III",  3) == 0) { v += 3;  p += 3; }
+	else if (strncmp(p, "II",   2) == 0) { v += 2;  p += 2; }
+	else if (strncmp(p, "I",    1) == 0) { v += 1;  p += 1; }
+
+	return v;
+}
+}
 
 // Init static members
 QMap<QString, QString> StelTranslator::iso639codes;
@@ -70,8 +101,57 @@ QString StelTranslator::qtranslate(const QString& s, const QString& c) const
 	return res;
 }
 
+QString StelTranslator::tryTranslateChineseStar(const QString& s, const QString& c) const
+{
+	static const auto re = []{ QRegularExpression re("(.+) ([IXVLCDM]+)$"); re.optimize(); return re; }();
+	const auto match = re.match(s);
+	if (!match.hasMatch()) return {};
+
+	const auto translatedConstellation = tryQtranslate(match.captured(1), c);
+	if (translatedConstellation.isEmpty()) return {};
+
+	const auto num = parseRomanNumeral(match.captured(2));
+	Q_ASSERT(num < 100);
+
+	static const QChar chars[10] = {
+		u'十',
+		u'一',
+		u'二',
+		u'三',
+		u'四',
+		u'五',
+		u'六',
+		u'七',
+		u'八',
+		u'九',
+	};
+
+	QString result = translatedConstellation;
+	int tens = num / 10;
+	const int units = num % 10;
+	if (tens >= 2)
+	{
+		result += chars[tens];
+		tens = 1;
+	}
+	if (tens == 1)
+	{
+		result += chars[0];
+	}
+	if (units)
+	{
+		result += chars[units];
+	}
+	return result;
+}
+
 QString StelTranslator::tryQtranslate(const QString &s, const QString &c) const
 {
+	if (getTrueLocaleName().startsWith("zh"))
+	{
+		const auto translated = tryTranslateChineseStar(s, c);
+		if (!translated.isEmpty()) return translated;
+	}
 	return translator->translate("", s.toUtf8().constData(),c.toUtf8().constData());
 }
 

src/core/StelTranslator.hpp

@@ -124,6 +124,8 @@ class StelTranslator
 private:
 	StelTranslator(const StelTranslator& );
 	const StelTranslator& operator=(const StelTranslator&);
+
+	QString tryTranslateChineseStar(const QString& s, const QString& c) const;
 
 	//! Initialize the languages code list from the passed file
 	//! @param fileName file containing the list of language codes