However, grouping photoreceptors loses details in the image, as fine details require a fine grid of photoreceptors, each detecting photons from one small point in space.

然而， 对感光器进行分组会丢失图像中的细节，因为精细的细节需要感光器的精细网格，每个感光器都从空间中的一个小点检测光子。

And this is done exactly as Leonardo does, you can look at the way the pen moves next to the contour to make this very fine grid of parallel shading and it's absolutely what Leonardo does.

这正是达芬奇的画法，你可以看到笔从轮廓线开始移动，画出一排细细的平行影线，这绝对是达芬奇的画法。

Here, a solution is proposed for the Eulerian approach, which means that we do not compute these quantities everywhere in the continuum of space, but we use a fine 3D grid, and we compute these quantities only in these gridpoints.

这里提出了一个基于欧拉方法的方案，这意味着我们不去计算这些遍布连续空间里的量，而是使用一个精细的三维网格，我们仅在这些网格点中计算这些量。

This issue can be alleviated by using a finer grid, which is, as we know, extremely costly to compute, or, the authors proposed a volume fixing method to take care of this without significantly increasing the execution time of the algorithm.

这方面可以用一个更加精细的网格来改善，就如我们所知的，它是极度耗费计算量的，又或者作者提出一个办法，既能解决体积问题，同时又不显著增加算法的运行时间。