Cannot build for Vita on Arch Linux

[EmmettCarpenter]

After following the instructions in the readme I get this error from cmake -DPLATFORM_VITA=ON -DCMAKE_BUILD_TYPE=Release ../ :

CMake Error at libcross2d/CMakeLists.txt:159 (find_package):
  By not providing "Findbox2d.cmake" in CMAKE_MODULE_PATH this project has
  asked CMake to find a package configuration file provided by "box2d", but
  CMake did not find one.

  Could not find a package configuration file provided by "box2d" with any of
  the following names:

    box2dConfig.cmake
    box2d-config.cmake

  Add the installation prefix of "box2d" to CMAKE_PREFIX_PATH or set
  "box2d_DIR" to a directory containing one of the above files.  If "box2d"
  provides a separate development package or SDK, be sure it has been
  installed.

I am currently running Manjaro Linux.