FIND_PACKAGE(Box2D)
IF(BOX2D_FOUND)
    ADD_SUBDIRECTORY(2DPhysics)
ENDIF(BOX2D_FOUND)

# Note that FindBullet requires CMake >= 2.8.4 to find Bullet >= 2.77 
# due to Bullet's header install directory location changing.
FIND_PACKAGE(Bullet)
IF(BULLET_FOUND)
    ADD_SUBDIRECTORY(3DPhysics)
ENDIF(BULLET_FOUND)
