fixed various caching issues when rapidly changing values

app/panel/viewer/viewer.cpp

@@ -74,6 +74,11 @@ void ViewerPanel::SetTimebase(const rational &timebase)
   viewer_->SetTimebase(timebase);
 }
 
+rational ViewerPanel::GetTime()
+{
+  return viewer_->GetTime();
+}
+
 void ViewerPanel::SetTexture(GLuint tex)
 {
   viewer_->SetTexture(tex);

app/panel/viewer/viewer.h

@@ -50,6 +50,8 @@ public:
 
   void SetTimebase(const rational& timebase);
 
+  rational GetTime();
+
 public slots:
   /**
    * @brief Set the texture to draw and draw it