save on exit message, * symbol on unsaved docs, saved status on history

engine/canvas.cpp

@@ -135,10 +135,13 @@ void ui::Canvas::clear(const glm::vec4& c/*={0,0,0,1}*/)
 {
     snap_history({ 0, 1, 2, 3, 4, 5 });
     m_layers[m_current_layer_idx].clear(c);
+    m_unsaved = true;
+    App::I.title_update();
 }
 void ui::Canvas::snap_history(const std::vector<int>& planes)
 {
     auto action = new ActionStroke;
+    action->was_saved = !m_unsaved;
     for (auto i : planes)
     {
         if (!m_layers[m_current_layer_idx].m_dirty_face[i])
@@ -462,7 +465,7 @@ void ui::Canvas::stroke_commit()
 {
     if (!m_dirty || m_layers.empty())
         return;
-    m_unsaved = true;
+
     m_dirty = false;
     m_dirty_stroke = true; // new stroke ready for timelapse capture
     App::I.redraw = true;
@@ -476,7 +479,11 @@ void ui::Canvas::stroke_commit()
     
     // allocate action to add to history
     auto action = new ActionStroke;
-    
+    action->was_saved = !m_unsaved;
+
+    m_unsaved = true;
+    App::I.title_update();
+
     // prepare common states
     glViewport(0, 0, m_width, m_height);
     glDisable(GL_BLEND);
@@ -854,6 +861,7 @@ void ui::Canvas::import_equirectangular_thread(std::string file_path)
     gl_state gl;
     gl.save();
     snap_history({0,1,2,3,4,5});
+    m_unsaved = true;
 
     Image img;
     img.load_file(file_path);