11.5.4. Storage Methods

Regardless of whether we want to use full precomputed lighting or to precalculate the transfer information and allow for some changes in the lighting, the resulting data has to be stored in some form. GPU-friendly formats are a must.

Light maps are one of the most common way of storing precomputed lighting. These are textures that store the precalculated information. Though sometimes terms such as irradiance map are used to denote a specific type of data stored, the term light maps is used to collectively describe all of these.

At runtime, the GPU’s built-in texture mechanisms are used. Values are usually bilinearly filtered, which for some representations might not be entirely correct. For example, when using an AHD representation, ...

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