Evaluates the element map. Maps a corner from the unit square [0,1]2 onto the element. The three vertices are (0, 0), (1, 0) and (1, 1). If you already have coordinates in the triangle, use duffyInv.
Returns a child. If no children exist, four new children are created. The triangle is cut into four new triangles by joining the midpoints of its edges.
Returns the Jacobian in a 2D linear map. The input is a point from [0,1]2, the output is the Jacobian of the map at the given point. The Jacobian includes the map from into the physical coordinates but not the map from to .
Returns the level of the cell. The level describes the refinements in both directions with respect to the parent cell in the initial mesh. This level information is taken into account when evaluating the element map or the Jacobian.