$halflambert
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January 2024
January 2024
$halflambert is a material shader parameter available in all 
Source games for VertexLitGeneric, Teeth, EyeRefract, VortWarp, Infected (shader). It is a boolean parameter that enables half-lambertian lighting, which wraps lighting further around a model to prevent it from losing definition. It only works on models.
Note:Since 
Source 2007, half-lambertian lighting is forcibly enabled on VertexLitGeneric regardless of $halflambert setting when $phong is enabled, unless $phongdisablehalflambert(in all games since 
) is enabled.Note:This parameter is disabled since 
due to conflicts with cascade shadow mapping.
Important:In 
Black Mesa half-lambertian for new light is broken. The result is that meshes with $phong or $halflambert get lit from ALL sides perpendicular to newlights, including ones with opposing normals. If you want to use $phong or $halflambert - you are able to fix this with adding in your VMT material parameter "$halflambert_gbuffer_off" "1".
Syntax
$halflambert 1
