Texlight
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A texlight is a light generated by the map compiler in front of a surface with a given texture, making it appear as if the texture is emitting light. Older compilers, such as QRAD and VRAD create a single large texlight in front of the texture, adding a new texlight for every subdivision. Modern compilers, such as ericw-tools, can instead create several smaller texlights across the textured face, making it look more like the texture is actually casting light, instead of looking like it has a light placed right on top of it.
Confirm: What method does VHLT use?
In 
Source, only RAD files can create texlights.
In 
GoldSrc, RAD files can be used, but they have been deprecated in ZHLT and VHLT by info_texlights and light_surface.
