This paper defines and discusses a set of rectangular all-sky projections that have no singular points, notably the Tesselated Octahedral Adaptive Spherical Transformation (or TOAST) developed initially for the WorldWide Telescope. These have proven to be useful as intermediate representations for imaging data where the application transforms dynamically from a standardized internal format to a specific format (projection, scaling, orientation, etc.) requested by the user. TOAST is strongly related to the Hierarchical Triangular Mesh pixelization and is particularly well adapted to situations where one wishes to traverse a hierarchy of images increasing in resolution. Because it can be recursively computed using a very simple algorithm it is particularly adaptable to use with graphical processing units.

中文翻译：

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基于八面体的投影作为计算机成像的中间表示形式：TOAST，TEA等。

本文定义并讨论了一组没有奇点的矩形全天空投影，尤其是最初为WorldWide望远镜开发的Tesselated八面体自适应球面变换（或TOAST）。这些已被证明可用作图像数据的中间表示，其中应用程序从标准化的内部格式动态转换为用户要求的特定格式（投影，缩放，方向等）。TOAST与“三角三角网格”像素化密切相关，并且特别适用于希望遍历分辨率提高的图像层次的情况。由于可以使用非常简单的算法来递归计算，因此特别适合与图形处理单元一起使用。