$allowdiffusemodulation
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$allowdiffusemodulation is a material shader parameter available in all Source games since 
Left 4 Dead (also in 
Mapbase) for VertexLitGeneric. It prevents a material from being tinted by either $color2 or the rendercolor parameter. This is useful for situations where you have a model made up of multiple materials, some which you might want tint-able and some not.
Note:This parameter exists as $notint in 
Counter-Strike: Global Offensive and 
Portal 2: Community Edition.Syntax
$allowdiffusemodulation <bool>
