Requirements for 64-bit Linux:

  * OptiX version 4.0+
  * GPU, driver, and CUDA toolkit supported by OptiX, as specified in the OptiX Release Notes
  * C++ compiler (gcc 4.8.4 has been tested)
  * CMake (http://www.cmake.org/cmake/resources/software.html).

Instructions for building:

  * Create a build directory other than the src/ directory.  Using a separate
    build directory allows multiple builds, differing in flavor, platform, etc.

  * cd to new directory.

  * Run
     $ ccmake <path>
    where path is the path to the src/ directory.  This will bring up
    the cmake interface.

  * Press 'c' within ccmake to begin configure process.

  * Set OptiX_INSTALL_DIR to wherever you installed OptiX, e.g., "/usr/local/NVIDIA-OptiX-SDK-<version>", 
    by moving the cursor over the field, hitting <enter>, changing the value, 
    and hitting <enter> again.

  * The newly added OptiX Introduction examples add a dependency for the DevIL image library.
    Under Linux these should be found automatically by the FindDevIL.cmake.
    If not, you can manually set the IL_INCLUDE_DIR, IL_LIBRARIES, ILU_LIBRARIES, and ILUT_LIBRARIES
    to the IL include path and libraries IL, ILU and ILUT respectively.
    
  * Adjust other options. You may want to change CMAKE_BUILD_TYPE to select a 
    Debug build rather than the default RELEASE build.

  * Press 'c' again to finish configure.

  * Press 'g' to generate Makefiles and exit.

  * Run
     $ make
   to build.

  * Executables should be found in the bin directory.