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Finally, we can render an image using these global illumination point clouds as textures. The 3D point clouds can be read in an OSL shader using the texture3d() function.

Figure~\ref{fig:global3d}(right) shows such an image, where the The box faces and the diffuse
diffuse teapot are rendered using the baked illumination data in the point cloud files. (For a more cache-friendly 3D texture format, the point clouds can be converted into brick maps using the `brickmake' utility program.)

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