Let $G$ be a graph of order $n$ such that for each vertex $v$ there is two associated vector $f_v, g_v\in R^n$ where $uv\in E(G)$ if and only if $\langle f_u - f_v , g_u-g_v \rangle \ge 0$. I need know about the class of graphs defined as above. [ISGCI][1] didn't know of such a class. > Have this class of graphs been studied before? What kind of properties do they have? Are they perhaps equivalent to some well-known graph class? [1]: http://www.graphclasses.org