thanks IOhannes,
it's compiling just fine:
PKG_ARTOOLKIT_CFLAGS="-Ihome/pat/11h11/yeux/artoolkit/include"
PKG_ARTOOLKIT_LIBS="-L/home/pat/11h11/yeux/artoolkit/lib -lAR"
./configure
--with-artoolkit-includes=/home/pat/11h11/yeux/artoolkit/include
--with-artoolkit-libs=/home/pat/11h11/yeux/artoolkit/lib
--with-artoolkit-libs --with-v4l2 --with-glversion=2.0 --enable-sse2
--enable-Vertex --without-avifile
pat