<html><head><style data-externalstyle="true"><!--
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p.MsoListParagraphCxSpFirst, li.MsoListParagraphCxSpFirst, div.MsoListParagraphCxSpFirst, p.MsoListParagraphCxSpMiddle, li.MsoListParagraphCxSpMiddle, div.MsoListParagraphCxSpMiddle, p.MsoListParagraphCxSpLast, li.MsoListParagraphCxSpLast, div.MsoListParagraphCxSpLast {
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--></style></head><body><div data-externalstyle="false" dir="ltr" style="font-family:Calibri,'Segoe UI',Meiryo,'Microsoft YaHei UI','Microsoft JhengHei UI','Malgun Gothic','Khmer UI','Nirmala UI',Tunga,'Lao UI',Ebrima,sans-serif;font-size:12pt;"><div>VTK is not easily usable from multiple threads. So, in general, you should restrict access to VTK objects to a single thread in your app, or use mutexes to guarantee that only one thread at a time has access to VTK objects. And, if you have to pick a thread to restrict the access to, use the same one that’s doing all the GUI stuff -- VTK rendering has to run in the GUI thread anyhow.</div><div> </div><div>HTH,</div><div>David C.</div><div> </div></div></body></html>