minor optimization

7 jobs for selection_pointcloud in 66 minutes and 42 seconds (queued for 1 second)
Status Name Job ID Coverage
  Test
passed clang-c++11-Qt5 #26590
Linux MultiThreads

00:10:53

passed cppcheck #26591
Linux MultiThreads

00:03:06

passed gcc-c++11-Qt5 #26589
Linux

00:03:40

passed Mac-Cpp11 #26595
Apple

00:38:26

passed VS2013-Qt-5.5.1-x64 #26594
VS2013 Qt551

00:25:22

passed VS2015-Qt-5.6.0-x32 #26593
VS2015 Qt56

00:22:11

passed VS2015-Qt-5.6.0-x64 #26592
VS2015 Qt56

00:26:46