uv2

uv2 is a label that appears in multiple disciplines and does not denote a single, universal concept. In 3D computer graphics, UV coordinates map a surface to a 2D texture. A second UV set—commonly referred to as UV2—is used to store an additional mapping, typically for lightmaps or secondary textures. Many engines, including Unity, rely on UV2 to bake lighting information separately from the base texture, enabling more accurate lighting without distorting the visible surface texture.

Beyond graphics, uv2 may simply be used as an identifier or variable name in software code to denote a second element of a 2D coordinate pair (u, v) or a second UV channel in mesh processing workflows. In such contexts, its meaning is defined by the surrounding data structure or library.

Some ultraviolet astronomy instruments organize data with filter labels that resemble UV components; for example, UVW2 is a common filter name in the Swift UVOT and related systems. However, "uv2" by itself is not a standardized scientific term for a specific function, and its meaning depends on the dataset or instrument documentation.

To determine the precise meaning of uv2 in a given context, refer to the relevant documentation, source code, data headers, or field conventions, paying attention to capitalization (UV2 vs uv2) and accompanying metadata.