public void RefreshMarkedSegmentGMeshes()
        {
            const bool check_for_decal_issues = false;

            foreach (Segment seg in m_level.GetMarkedSegments())
            {
                foreach (Side side in seg.side)
                {
                    m_level.RefreshSideGMeshes(side, check_for_decal_issues);
                }
            }
            gl_panel.BuildLevelGMesh();
        }