--- a/QTfrontend/ui/widget/drawmapwidget.cpp Sat Mar 17 17:47:42 2018 +0100+++ b/QTfrontend/ui/widget/drawmapwidget.cpp Sat Mar 17 23:55:32 2018 +0300@@ -63,6 +63,9 @@ { Q_UNUSED(event);+ if(!m_scene)+ return;+ int height = this->height(); int width = this->width();