<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">Hello,<div><br></div><div>I have not been using GATE for almost a year, and a few days ago, when I try to implement a code, the following messages appear, which I have not seen before, does anyone know what the problem is? I guess it is the OpenGL problem , but not really sure, and do not know how to fix it. I am running GATE on macbook pro with osx 10.9.5.</div><div><br></div><div>Thanks and best regards,</div><div>Cheng</div><div><br></div><div><div style="margin: 0px; font-size: 11px; font-family: Menlo;">Idle> /control/execute TwoLayers.mac</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;">G4OpenGLXViewer::G4OpenGLXViewer: unable to get a single buffer visual.</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;">G4OpenGLXViewer::G4OpenGLXViewer: unable to get a double buffer visual.</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;">G4OpenGLXViewer::G4OpenGLXViewer: unable to get required visuals.</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;">G4OpenGLImmediateX::CreateViewer: error flagged by negative view id in G4OpenGLImmediateXViewer creation.</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;"> Destroying view and returning null pointer.</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;">ERROR in G4VisManager::CreateViewer during OpenGLImmediateX viewer creation.</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;"> No action taken.</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;">WARNING: No viewer created.</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;">ERROR: Viewer "none" not found - "/vis/viewer/list" to see possibilities.</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;">ERROR: G4VisCommandsViewerSet::SetNewValue: no current viewer.</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;">ERROR: G4VisCommandsViewerPan::SetNewValue: no current viewer.</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;">ERROR: G4VisCommandsViewerZoom::SetNewValue: no current viewer.</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;">ERROR: G4VisCommandsViewerSet::SetNewValue: no current viewer.</div></div></body></html>