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During rendering, whenever 3Delight encounters a non-optimized texture, it will optimize a create an optimized copy automatically. The optimized texture will be saved at the same location and will have the same base name as the associated non-optimized texture, but with a .tdl extension added. This process will skip any texture that have the .tdl substring in the file name (e.g. texname.tdl.tif and texname.tif.tdl will be considered as optimized).
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