在3D電腦圖學已經被廣泛的應用中，要繪出高品質的畫質是非常必要的，而在以點為基礎的繪圖中，Surfels和Surface splatting是目前很重要的代表，因為利用它們可以繪出高品質的繪圖效果。
所以，在這篇論文中，我們選擇它們並對其作些許的調整和改變，主要目的是為了可以利用先進的顯示卡來達到更快和讓記憶體的使用更有效率的繪圖。更改之處可以分為三個部分，第一個部分是，我們改變Surfels在LDC的儲存方式，使得要繪製一個3D圖形的所需的預備資訊降低，但是仍維持住一定的圖形品質。第二個部分是，我們更改Object-Space EWA surface splatting的方法，使得可以利用硬體來支援multisampling和anisotropic texture filtering這二個特性，並且具備了視點獨立的優點。第三個部分是，我們提出一個利用bi-linearly計算filter weight以取代傳統的用歐幾里德距離(Euclidean distance)的方法。

Surfel is an important representation for point-based graphics because of the high-quality rendering it enables.

In this work, we present three modifications to surfels to make it more memory efficient and easier to render using modern graphics hardware. First, we assign surfels to LDC faces based on the normal vectors. It removes the need for 3-to-1 reduction while maintaining the same image quality, thus making LDC more memory efficient. Second, we modify object-space EWA surface splatting to utilize the multisampling and texture filtering features of modern graphics hardware. It removes the step of warping a low-pass filter to object space from the process of object-space EWA surface splatting. Third, we propose to calculate the filter weight bi-linearly instead of using Euclidean distances. The filter weights in X and Y directions are computed in 1D separately and then multiplied together. It makes the summation of filter weights approximate a partition of unity more closely, thus reduces the
artifacts in absence of per-surfel or per-pixel normalization.

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