anchor.diff:  , libXxf86vm, libICE
   , unzip
   , libXrender
  +, SDL2
   , withNvidiaCg ? false, nvidia_cg_toolkit
   , withSamples ? false }:
   
  
positive.code:      sha256 = "1iv6k0dwdzg5nnzw2mcgcl663q4f7p2kj7nhs8afnsikrzxxgsi4";
    };
  
    cmakeFlags = [ "-DOGRE_BUILD_SAMPLES=${toString withSamples}" ]
      ++ map (x: "-DOGRE_BUILD_PLUGIN_${x}=on")
             ([ "BSP" "OCTREE" "PCZ" "PFX" ] ++ lib.optional withNvidiaCg "CG")
      ++ map (x: "-DOGRE_BUILD_RENDERSYSTEM_${x}=on") [ "GL" ];
  
negative.code:      libX11 libXmu libSM
       libXxf86vm libICE
       libXrender
       SDL2
     ] ++ lib.optional withNvidiaCg nvidia_cg_toolkit;
  
    meta = {
  