Splat/Mesh Blending, Perspective Rasterization and Transparency for Point-Based RenderingEurographics Symposium on Point-Based Graphics, 2006, Boston, United-States.
In this paper we present multiple simple and efficient improvements for splatting based rendering systems. In a first step we derive a perspectively correct splat rasterization algorithm suitable for both efficient implementation on current GPU and the design of fast dedicated rasterization units taking advantages of incremental calculations. Next, we propose a new efficient and high-quality approximation of the optimal EWA (Elliptical Weighted Average) filtering framework. We also show how transparent point-clouds can be rendered by current GPU in an order independent way by using a modified depth-peeling approach. Finally, in the context of hybrid points and polygons rendering systems, we present a simple mechanism to smooth the transitions between the different representations. Combined to previous contributions in the field, these improvements lead to a high-quality, performant and full-featured hardware-oriented splatting rendering system.
EWA filtering approximations: left is the Mario Botsch's approximation and right is our new approximation.
Splat/polygon transition smoothing. Left: classic hybrid rendering (look at the discontinuity artifacts). Center: the gradient is the sum of weight comming from the splatting process. Right: the previous gradient is used to smooth the transition without additionnal cost !
Transparency: from left to right, full depth-peeling (8 layers), depth-peeling with only 3 layers without and with our blending heuristic.