present3D application. As static-link present3d should depend on
freetype, png, pdf and some other plugins, any mis-compiling of these
plugins will make present3d fail to be built. Some lirbaries like
poppler and cairo are not popular under Windows, so it is very common
that we don't have osgdb_pdf compiled and thus get errors when
building present3d. I've modified the CMakeLists and present3d.cpp to
avoid this problem."