Comment 9 for bug 1704459

please reject proj, the issue is that pcl needs an explicit dependency, because vtk6 lost the direct one for the -dev package.

The really nice fix would have been to cherry-pick the vtk6 revert to use the internal proj library, but this is unfeasible since it is an ABI change. (see debian bug: #819741)

now, the smartest solution I could think is to add libproj-dev to pcl dependencies, even if this might result in an ABI break too.
https://launchpad.net/~costamagnagianfranco/+archive/ubuntu/locutusofborg-ppa/+packages
please test this package and specially pcl reverse-dependencies in xenial with this updated version

fixing vtk6 will require checks/rebuilds of ~10 reverse-dependencies (many of them might have been already built with the old vtk with embedded proj, so no change for them), while fixing pcl means only one reverse-dependency to check/fix
"ros-pcl-conversions"

so at the end, please test, and in case you agree with my analysis, reject proj and accept pcl