Adding pcl. (Also updating flann, reworking vtk)

pkgs/development/libraries/vtk/default.nix

@@ -16,12 +16,20 @@ stdenv.mkDerivation rec {
     url = "${meta.homepage}files/release/${majorVersion}/vtk-${version}.tar.gz";
     md5 = "a0363f78910f466ba8f1bd5ab5437cb9";
   };
+
   buildInputs = [ cmake mesa libX11 xproto libXt ]
     ++ optional useQt4 qt4;
 
-  cmakeFlags = optional useQt4
+  # Shared libraries don't work, because of rpath troubles with the current
+  # nixpkgs camke approach. It wants to call a binary at build time, just
+  # built and requiring one of the shared objects.
+  # At least, we use -fPIC for other packages to be able to use this in shared
+  # objects.
+  cmakeFlags = [ "-DCMAKE_C_FLAGS=-fPIC" "-DCMAKE_CXX_FLAGS=-fPIC" ] ++ optional useQt4
     [ "-DVTK_USE_QT:BOOL=ON" ];
 
+  enableParallelBuilding = true;
+
   meta = {
     description = "Open source libraries for 3D computer graphics, image processing and visualization";
     homepage = http://www.vtk.org/;