Cycles para Gaffer

Buenas tardes, alguien sabe como compilar cycles para gaffer? eh estado probando gaffer y esto me ayudaria para hacer lookdev a mis trabajos tengo entendido es algo parecido a Katana the Foundry github.com/boberfly/GafferCycles . Sigo los pasos para compilar en linux mint pero me da un error en la terminal Algo asi...

$ cmake -DCMAKE_CXX_COMPILER=g++-6 -DGAFFER_ROOT=$GAFFER_ROOT -DCMAKE_INSTALL_PREFIX=$GAFFERCYCLES ..
-- The CXX compiler identification is unknown
CMake Error at cycles/CMakeLists.txt:42 (project):
  The CMAKE_CXX_COMPILER:

    g++-6

  is not a full path and was not found in the PATH.

  Tell CMake where to find the compiler by setting either the environment
  variable "CXX" or the CMake cache entry CMAKE_CXX_COMPILER to the full path
  to the compiler, or to the compiler name if it is in the PATH.


-- Configuring incomplete, errors occurred!
See also "/home/gersin/GafferCycles/build/CMakeFiles/CMakeOutput.log".
See also "/home/gersin/GafferCycles/build/CMakeFiles/CMakeError.log".

Gracias por la ayuda...