The $hdrscale parameter is only present in the DX11 version of the shader This shader adds an $hdrscale parameter that functions as a multiplier for the final result, so an $hdrscale of 2 is equivalent to having $mod2x.
Examples:
$hdrscale 1 $hdrscale 2 $hdrscale 10
The Physically Based Rendering (PBR) shader is a powerful new shader that provides more realistic and versatile rendering of brushes and models within Momentum Mod whilst using fewer textures and needing fewer VMT tweaks.
PBR extends Source’s shading capacity by storing additional Metalness, Roughness and Ambient Occlusion maps in independent channels of an additional texture called the MRAO.
Additionally, it uses the alpha channel of the normal map as a height input for parallax maps.
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