From d928d6e47e245cdb0a66a66ab8c5dc732e84ece8 Mon Sep 17 00:00:00 2001
From: Lukas Matena <lukasmatena@seznam.cz>
Date: Tue, 12 May 2020 14:03:10 +0200
Subject: [PATCH] Hollowing gizmo fix: selection of single holes was recently
 broken

---
 src/slic3r/GUI/Gizmos/GLGizmoHollow.cpp | 5 ++++-
 src/slic3r/GUI/Gizmos/GLGizmoHollow.hpp | 2 ++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/slic3r/GUI/Gizmos/GLGizmoHollow.cpp b/src/slic3r/GUI/Gizmos/GLGizmoHollow.cpp
index b248db1c6..8d4616da3 100644
--- a/src/slic3r/GUI/Gizmos/GLGizmoHollow.cpp
+++ b/src/slic3r/GUI/Gizmos/GLGizmoHollow.cpp
@@ -58,7 +58,10 @@ void GLGizmoHollow::set_sla_support_data(ModelObject*, const Selection&)
 
     const ModelObject* mo = m_c->selection_info()->model_object();
     if (mo) {
-        reload_cache();
+        if (m_old_mo_id != mo->id()) {
+            reload_cache();
+            m_old_mo_id = mo->id();
+        }
         if (m_c->hollowed_mesh() && m_c->hollowed_mesh()->get_hollowed_mesh())
             m_holes_in_drilled_mesh = mo->sla_drain_holes;
     }
diff --git a/src/slic3r/GUI/Gizmos/GLGizmoHollow.hpp b/src/slic3r/GUI/Gizmos/GLGizmoHollow.hpp
index 3ee83c345..93e577743 100644
--- a/src/slic3r/GUI/Gizmos/GLGizmoHollow.hpp
+++ b/src/slic3r/GUI/Gizmos/GLGizmoHollow.hpp
@@ -43,6 +43,8 @@ private:
     void hollow_mesh(bool postpone_error_messages = false);
     bool unsaved_changes() const;
 
+    ObjectID m_old_mo_id = -1;
+
     // bool  m_show_supports = true;
     float m_new_hole_radius = 2.f;        // Size of a new hole.
     float m_new_hole_height = 6.f;