Gui : susbtitute dot with local decimal separator for spin boxes

Main goal is to improve user-friendlyness for several locales
 Substitution of dot is performed :
 * Always if dot is neither decimal nor group/thousand separator of current locale
 * Only on NUMPAD dot if dot is not decimal but is group separator of current locale

src/Gui/Application.cpp

@@ -2080,6 +2080,12 @@ void Application::runApplication(void)
         WheelEventFilter* filter = new WheelEventFilter(&mainApp);
         mainApp.installEventFilter(filter);
     }
+    
+    //filter keyboard events to substitute decimal separator
+    if (hGrp->GetBool("SubstituteDecimalSeparator", false)) {
+        KeyboardFilter* filter = new KeyboardFilter(&mainApp);
+        mainApp.installEventFilter(filter);
+    }
 
 #if defined(HAVE_QT5_OPENGL)
     {

src/Gui/GuiApplication.cpp

@@ -26,12 +26,14 @@
 #ifndef _PreComp_
 # include <sstream>
 # include <stdexcept>
+# include <QAbstractSpinBox>
 # include <QByteArray>
 # include <QComboBox>
 # include <QDataStream>
 # include <QDebug>
 # include <QFileInfo>
 # include <QFileOpenEvent>
+# include <QKeyEvent>
 # include <QSessionManager>
 # include <QTimer>
 #endif
@@ -323,5 +325,29 @@ bool WheelEventFilter::eventFilter(QObject* obj, QEvent* ev)
     return false;
 }
 
+KeyboardFilter::KeyboardFilter(QObject* parent)
+  : QObject(parent)
+{
+}
+
+bool KeyboardFilter::eventFilter(QObject* obj, QEvent* ev)
+{
+    if (ev->type() == QEvent::KeyPress || ev->type() == QEvent::KeyRelease) {
+        QKeyEvent *kev = static_cast<QKeyEvent *>(ev);
+        QAbstractSpinBox *target = dynamic_cast<QAbstractSpinBox *>(obj);
+        if (kev->key() == Qt::Key_Period && target)
+        {
+            QChar decimalPoint = QLocale().decimalPoint();
+            QChar groupSeparator = QLocale().groupSeparator();
+            if (decimalPoint != Qt::Key_Period && (groupSeparator != Qt::Key_Period || (kev->modifiers() & Qt::KeypadModifier))) {
+                QKeyEvent modifiedKeyEvent(kev->type(), decimalPoint.digitValue(), kev->modifiers(), QString(decimalPoint), kev->isAutoRepeat(), kev->count());
+                qApp->sendEvent(obj, &modifiedKeyEvent);
+                return true;
+            }
+        }
+    }
+    return false;
+}
+
 
 #include "moc_GuiApplication.cpp"

src/Gui/GuiApplication.h

@@ -92,6 +92,15 @@ public:
     bool eventFilter(QObject* obj, QEvent* ev);
 };
 
+class KeyboardFilter : public QObject
+{
+    Q_OBJECT
+
+public:
+    KeyboardFilter(QObject* parent);
+    bool eventFilter(QObject* obj, QEvent* ev);
+};
+
 }
 
 #endif // GUI_APPLICATION_H