$mraotexture
$mraotexture is a s2 available in 
Strata Source, 
Titanfall branch, and 
Hunt Down the Freeman.
Warning:
- The {{{game}}} parameter is inconsistent with the name defined by the {{Strata}} template. This can most likely be fixed by setting the value of the {{{game}}} parameter to Strata Source.
If a parameter is consistent but you're still seeing this warning, it may be an issue with the template itself. Please discuss it on the template's talk page.
It is available exclusively for the PBR shader to define the MRAO map to use for the Physically Based Rendering effects.
Physically Based Rendering
Physically Based Rendering is a photorealistic shading technique that takes lighting information about the metalness, roughness, and ambient occlusion of a texture and then renders lighting in a realistic manner. Most modern game engines utilize PBR for most of their textures, and unfortunately due to the 
Source engine's age, it is not supported by all the official Valve branches. However, some third party games and engine branches support this shader.
What is an MRAO map?
An MRAO (M etalness, R oughness, Ambiemt Occlusion) map is a texture that contains lighting information on the metalness, shininess, and self-shadowing of the diffuse (a.k.a base, albedo) texture through the intensity of the RGB channels. This reduces the amount of texture maps needed for one PBR material from 5 to 3, reducing file space and memory cost. However, image editing programs often do not have an easy way to make these textures. Thankfully, there are a couple of methods to create these textures that work.
User:Equalizer5118/Adding PBR Textures to Supported Games/en
See Also
External Links
- https://www.adobe.com/products/substance3d/discover/pbr.html - All You Need To Know About PBR (Adobe.com)