KhronosGroup/glTF — pull request #160 by Geenz (2013-10-21 17:53:52+00:00)
Title: Series of OS X-related compilation fixes.

When compiling with clang and libc++ under OS X, neither the tr1 namespace or its related directories exist. This is fairly specific to libc++. Clang on the other hand complains about the IVec3Cmp functor, failing somewhere in the map template. Marking the () operator as const resolves this.