Hardware implementation of the subdivision loop algorithm

The demand for higher quality in the graphical representation of 3D scenes is continuously increasing. Subdivision of triangular meshes is one of the most employed techniques for improving the quality of these rendered images. The high communication requirements between the CPU and the graphics system associated with this kind of method can be considerably reduced if the subdivision task is carried out in hardware, within a new unit placed at the entry of the standard graphics pipeline. In this paper we present a comparative analysis of two possible implementations of this hardware unit, corresponding to two different alternatives for applying Loop subdivision to triangle meshes: subdivsion based on forward differencing and on meshing scheme. In the first case, the amount of information sent to the graphics pipeline grows linearly with the level of subdivision; whereas, with the meshing scheme the communication requirements are lower and independent of the subdivision level.