Abstract: In this paper,we first reconstruct a second order polynomial surface to approximate the original point model in the local area of each point,which is then restricted within a so-called ε-confidence region,producing a ε-surfel.The surfels form a tight approximation to the original model with errors within ε everywhere,and can be used to compute the ray intersection with the original point model.Experimental results show that our local surface reconstruction and ray-tracing method is fast,with high approximation accuracy and high rendering quality,and is also adaptive to models with different sampling densities.