 Toric blowup along an orbit closure

On a smooth toric variety, the blowup along the orbit closure in a toric variety of a cone generated by part of a lattice basis $v_1,\dots ,v_k$ is the star subdivision at their sum. Locally the center has ideal $(x_1,\dots ,x_k)$; its blowup charts adjoin $x_j/x_i$, producing precisely these subdivided cones. This extends the toric blowup at a torus-fixed point to invariant centers of any codimension.