If you''re looking to sub-divide a BS, you''re going to get some gaps because the spheres don''t fill all the space. I guess this would be quite easy though. Just create center points and radii for each subdivision that you want. I''m not sure what you''re trying to do, but if you had, for example, an arm, you could use a BS for the entire arm, then add three extra ones for the shoulder, the elbow and the hand and then test for each of those. I don''t know if you could use the built-in DX BS tests, but you could very easily create your own (centerpoint+radius) - (centerpoint2+radius2) < 0 = hit.