[GUI] GUI crashes sometimes with NullPointerException

Summary

When using the button Run all scenarios, the GUI simulates several scenario files properly but than a NullPointerException is raised and the GUI does not respond anymore. See the attached stack trace for more details.

Steps to reproduce

As the exception is thrown only sometimes, I guess it is hard to reproduce the problem (maybe some race condition between GUI thread and simulation thread?).

At the moment, I am working on psychology branch, but it also occurs on master sometimes.

Relevant data

• [If you report a bug] Git branch name and commit hash: psychology/91176052
• [If you report a bug in a scenario] Use test project "Scenarios/ModelTests/TestPsychology/CognitionAndBehavior/"

Logs and outputs

NullPointerException after running eight scenarios

09:58:37,941   INFO ProjectView:169 - scenario 08-CounterFlow-OSMSequential-SBEnabled-SearchRadiusAdapted finished
09:58:37,988   INFO ScenarioRun:177 - Simulation of scenario 08-CounterFlow-OSMSequential-SBEnabled-SearchRadiusAdapted finished.
09:58:37,988   INFO ScenarioRun:124 - Initializing scenario. Start of scenario '09-OriginalExperimentSetup-OSMEventDriven'...
09:58:37,989   INFO ScenarioRun:126 - StartIt 09-OriginalExperimentSetup-OSMEventDriven
09:58:37,989   INFO ScenarioRun:105 - scenario context initialized.
09:58:37,994   INFO PotentialFieldDistancesBruteForce:47 - initialize floor field (PotentialFieldDistancesBruteForce)
09:58:38,037   INFO PotentialFieldDistancesBruteForce:82 - floor field initialization time:42[ms]
09:58:38,037   INFO Topography:351 - Set PedestrianIdCount to start value: 14
09:58:38,051   INFO EikonalSolverDefaultProvider:23 - floor field initialization time:12[ms]
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
	at org.vadere.gui.components.view.DefaultRenderer.transformGraphics(DefaultRenderer.java:124)
	at org.vadere.gui.components.view.DefaultRenderer.renderGraphics(DefaultRenderer.java:86)
	at org.vadere.gui.components.view.DefaultRenderer.renderImage(DefaultRenderer.java:97)
	at org.vadere.gui.components.view.DefaultRenderer.render(DefaultRenderer.java:68)
	at org.vadere.gui.onlinevisualization.view.OnlinevisualizationRenderer.render(OnlinevisualizationRenderer.java:37)
	at org.vadere.gui.components.view.ScaleablePanel.paintComponent(ScaleablePanel.java:108)
	at java.desktop/javax.swing.JComponent.paint(JComponent.java:1074)
	at java.desktop/javax.swing.JComponent.paintChildren(JComponent.java:907)
	at java.desktop/javax.swing.JComponent.paint(JComponent.java:1083)
	at java.desktop/javax.swing.JViewport.paint(JViewport.java:737)
	at java.desktop/javax.swing.JComponent.paintChildren(JComponent.java:907)
	at java.desktop/javax.swing.JComponent.paint(JComponent.java:1083)
	at java.desktop/javax.swing.JComponent.paintChildren(JComponent.java:907)
	at java.desktop/javax.swing.JSplitPane.paintChildren(JSplitPane.java:1024)
	at java.desktop/javax.swing.JComponent.paint(JComponent.java:1083)
	at java.desktop/javax.swing.JComponent.paintChildren(JComponent.java:907)
	at java.desktop/javax.swing.JComponent.paint(JComponent.java:1083)
	at java.desktop/javax.swing.JComponent.paintToOffscreen(JComponent.java:5255)
	at java.desktop/javax.swing.RepaintManager$PaintManager.paintDoubleBufferedImpl(RepaintManager.java:1643)
	at java.desktop/javax.swing.RepaintManager$PaintManager.paintDoubleBuffered(RepaintManager.java:1618)
	at java.desktop/javax.swing.RepaintManager$PaintManager.paint(RepaintManager.java:1556)
	at java.desktop/javax.swing.BufferStrategyPaintManager.paint(BufferStrategyPaintManager.java:262)
	at java.desktop/javax.swing.RepaintManager.paint(RepaintManager.java:1323)
	at java.desktop/javax.swing.JComponent._paintImmediately(JComponent.java:5203)
	at java.desktop/javax.swing.JComponent.paintImmediately(JComponent.java:5013)
	at java.desktop/javax.swing.RepaintManager$4.run(RepaintManager.java:865)
	at java.desktop/javax.swing.RepaintManager$4.run(RepaintManager.java:848)
	at java.base/java.security.AccessController.doPrivileged(Native Method)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85)
	at java.desktop/javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:848)
	at java.desktop/javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:823)
	at java.desktop/javax.swing.RepaintManager.prePaintDirtyRegions(RepaintManager.java:772)
	at java.desktop/javax.swing.RepaintManager$ProcessingRunnable.run(RepaintManager.java:1890)
	at java.desktop/java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:313)
	at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:770)
	at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:721)
	at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:715)
	at java.base/java.security.AccessController.doPrivileged(Native Method)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85)
	at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:740)
	at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
	at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90)
Process finished with exit code 130 (interrupted by signal 2: SIGINT)