add warning if total parametric volume is less then 1

6 jobs for master in 8 minutes and 6 seconds (queued for 2 seconds)
latest
Status Job ID Name Coverage
  Build
passed #129984
Linux
clang-c++11

00:03:58

passed #129988
Linux
clang-c++14

00:08:06

passed #129980
Linux
gcc-c++11

00:01:44

passed #129986
Linux
gcc-c++14

00:01:47

passed #129989
Apple
macos-c++11

00:05:08

passed #129990
Apple
macos-c++14

00:02:55