fix thrown exception on application terminate
fix thrown exception on application terminate

favreau/OSPRay,Twinklebear/OSPRay,Twinklebear/OSPRay,MengjiaoH/ospray,wilsonCernWq/ospray,wilsonCernWq/ospray,ospray/OSPRay,MengjiaoH/ospray,ospray/OSPRay,ospray/OSPRay,favreau/OSPRay,favreau/OSPRay,Twinklebear/OSPRay,favreau/OSPRay,Twinklebear/OSPRay,ospray/OSPRay,wilsonCernWq/ospray,MengjiaoH/ospray,MengjiaoH/ospray,MengjiaoH/ospray