Fig. 6
From: Contact modeling from images using cut finite element solvers

Linear approximation of the hip bone surface triangulation in regular background mesh with two refinement steps of all elements which collide with the surface triangulations of the hip and femur bone. The figures a–c show elements marked as interior as blue, marked as colliding with green and marked as outside with red. The figures d–f shows all the elements which are fully inside the hip bone geometry