Draw the arc we are creating

src/Editor/DearImGui/Drawable.cpp

@@ -77,6 +77,32 @@ static void drawArrow(ImDrawList* draw_list, ImVec2 const& A, ImVec2 const& B,
     draw_list->AddConvexPolyFilled(points.data(), points.size(), color);
 }
 
+//------------------------------------------------------------------------------
+void drawArc(ImDrawList* draw_list, Node* from, Node* to, ImVec2* click_position, ImVec2 const& origin, ImVec2 const& cursor)
+{
+    if (from != nullptr)
+    {
+        drawArrow(draw_list,
+                  origin + ImVec2(from->x, from->y),
+                  origin + ImVec2(cursor.x, cursor.y),
+                  OUTLINE_COLOR);
+    }
+    else if (to != nullptr)
+    {
+        drawArrow(draw_list,
+                  origin + ImVec2(cursor.x, cursor.y),
+                  origin + ImVec2(to->x, to->y),
+                  OUTLINE_COLOR);
+    }
+    else if (click_position != nullptr)
+    {
+        drawArrow(draw_list,
+                  origin + ImVec2(click_position->x, click_position->y),
+                  origin + ImVec2(cursor.x, cursor.y),
+                  OUTLINE_COLOR);
+    }
+}
+
 //------------------------------------------------------------------------------
 void drawArc(ImDrawList* draw_list, Arc const& arc, TypeOfNet const type, ImVec2 const& origin, float const alpha)
 {

src/Editor/DearImGui/Drawable.hpp

@@ -33,7 +33,7 @@ static const float TRANS_HEIGHT = TRANS_WIDTH / 3.0f;  // Rectangle height for r
 static const float PLACE_RADIUS = TRANS_WIDTH / 2.0f; // Circle radius for rendering Places
 static const float TOKEN_RADIUS = 2.0f;  // Circle radius for rendering tokens
 
-
+void drawArc(ImDrawList* draw_list, Node* from, Node* to, ImVec2* click_position, ImVec2 const& origin, ImVec2 const& cursor);
 void drawArc(ImDrawList* draw_list, Arc const& arc, TypeOfNet const type, ImVec2 const& origin, float const alpha);
 void drawToken(ImDrawList* draw_list, float const x, float const y);
 void drawTimedToken(ImDrawList* draw_list, size_t tokens, float const x, float const y);

src/Editor/PetriEditor.cpp

@@ -1600,6 +1600,11 @@ void Editor::PetriView::drawPetriNet(Net& net, Simulation& simulation)
         it->y = m_mouse.position.y;
     }
 
+    // Show the arc we are creating
+    drawArc(m_canvas.draw_list, m_mouse.from, m_mouse.to,
+            m_mouse.arc_from_unknown_node ? &m_mouse.click_position : nullptr,
+            origin, m_mouse.position);
+
     // Draw critical cycle
     //for (auto& a: m_marked_arcs)
     //    draw(*a, 255);