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Render courtesy of Wieger Poutsma - FISK Imaging (www.fisk-imaging.com). Client: 361º Sports
Texture mapping defines the way a tridimensional object is mapped into the bidimensional space of a texture. It is basically the mapping from a 3D space (where the vertices have three coordinates) into a 2D one (where they only have two, horizontal and vertical). Normally this step is prior to the texturing phase, in which the model needs to be unwrapped into a 2D coordinates system that defines how the texture fits onto the object.
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UDIM and other Tiled Texture formats
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UDIM (developed by Foundry's Mari) and other Tiled Texture formats are basically an evolution of the UV concept. The main drawback of the traditional UV map is that you can not have different mapping resolutions for each part of the model. If you have one single UV map for the entire model, and a specific part of the model needs to be highly detailed, for example the face, you are forced to make the entire body texture at that high resolution, creating large files unnecessarily.
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