Gui: fix NaviCube in split views (fixes #9500)

* initialize base and hilite color with more sensible default values
* handle case if no font name is set
* apply user preferences to NaviCube

src/Gui/NaviCube.cpp

@@ -241,11 +241,13 @@ void NaviCube::setSize(int size)
 {
     m_NaviCubeImplementation->setSize(size);
 }
+
 void NaviCube::setChamfer(float chamfer)
 {
     m_NaviCubeImplementation->m_Chamfer = min(max(0.05f, chamfer), 0.18f);
     m_NaviCubeImplementation->m_Prepared = false;
 }
+
 void NaviCube::setNaviRotateToNearest(bool toNearest)
 {
     m_NaviCubeImplementation->m_RotateToNearest = toNearest;
@@ -301,7 +303,6 @@ void NaviCube::setBorderWidth(double BorderWidth)
     m_NaviCubeImplementation->m_BorderWidth = BorderWidth;
 }
 
-
 void NaviCube::setShowCS(bool showCS)
 {
     m_NaviCubeImplementation->m_ShowCS = showCS;
@@ -311,6 +312,7 @@ void NaviCube::setNaviCubeLabels(const std::vector<std::string>& labels)
 {
     m_NaviCubeImplementation->setLabels(labels);
 }
+
 void NaviCubeImplementation::setLabels(const std::vector<std::string>& labels)
 {
     m_LabelTextures[PickId::Front].label  = labels[0];
@@ -322,8 +324,9 @@ void NaviCubeImplementation::setLabels(const std::vector<std::string>& labels)
     m_Prepared = false;
 }
 
-
 NaviCubeImplementation::NaviCubeImplementation(Gui::View3DInventorViewer* viewer)
+    : m_BaseColor{226, 232, 239}
+    , m_HiliteColor{170, 226, 255}
 {
     m_View3DInventorViewer = viewer;
     m_PickingFramebuffer = nullptr;
@@ -368,6 +371,10 @@ auto convertWeights = [](int weight) -> QFont::Weight {
 };
 
 int imageVerticalBalance(QImage p, int sizeHint) {
+    if (sizeHint < 0) {
+        return 0;
+    }
+
     int h = p.height();
     int startRow = (h - sizeHint) / 2;
     bool done = false;
@@ -394,8 +401,10 @@ void NaviCubeImplementation::createCubeFaceTextures() {
     int texSize = 192; // Works well for the max cube size 1024
     // find font sizes
     QFont font;
-    QString fontString = QString::fromStdString(m_TextFont);
-    font.fromString(fontString);
+    if (!m_TextFont.empty()) {
+        QString fontString = QString::fromStdString(m_TextFont);
+        font.fromString(fontString);
+    }
     if (m_FontWeight > 0) {
         font.setWeight(convertWeights(m_FontWeight));
     }

src/Gui/SplitView3DInventor.cpp

@@ -110,6 +110,12 @@ void AbstractSplitView::setupSettings()
     viewSettings->ignoreRenderCache = true;
     viewSettings->ignoreDimensions = true;
     viewSettings->applySettings();
+
+    for (auto view : _viewer) {
+        NaviCubeSettings naviSettings(App::GetApplication().GetParameterGroupByPath
+                                     ("User parameter:BaseApp/Preferences/NaviCube"), view);
+        naviSettings.applySettings();
+    }
 }
 
 View3DInventorViewer* AbstractSplitView::getViewer(unsigned int n) const

src/Gui/View3DSettings.cpp

@@ -449,6 +449,7 @@ NaviCubeSettings::~NaviCubeSettings()
 {
     connectParameterChanged.disconnect();
 }
+
 QString NaviCubeSettings::getDefaultSansserifFont()
 {
     // "FreeCAD NaviCube" family susbtitutions are set in MainWindow::MainWindow
@@ -458,6 +459,7 @@ QString NaviCubeSettings::getDefaultSansserifFont()
     return QFontInfo(font).family();
     // return QStringLiteral("FreeCAD NaviCube");
 }
+
 void NaviCubeSettings::applySettings()
 {
     parameterChanged("BaseColor");
@@ -519,7 +521,7 @@ void NaviCubeSettings::parameterChanged(const char* Name)
         nc->setBaseColor(App::Color::fromPackedRGBA<QColor>(col));
         // update default contrast colors
         parameterChanged("EmphaseColor");
-   }
+    }
     else if (strcmp(Name, "EmphaseColor") == 0) {
         App::Color bc((uint32_t)hGrp->GetUnsigned("BaseColor", 3806916544));
         unsigned long d = bc.r + bc.g + bc.b >= 1.5f ? 255 : 4294967295;