The V-Ray Rock texture generates a procedural rock pattern using two colors or texture maps.  

UI Path: ||V-Ray Node Editor|| > Shader > Add > Textures > V-Ray Rock

Mapping – This slot allows you to connect a Mapping node (UVW Mapping, UWV Randomizer) to adjust the UWVs of the texture. 

Color 1 (input socket) – Input for the first color texture.

Color 2 (input socket) – Input for the second color texture.

Compatibility With – Allows you to match the result of the texture in Blender to that in either 3ds Max or Maya.

Max – The resulting alpha of the texture is the intensity of the texture.
Maya – The resulting alpha of the texture is the color luminescence.

Invert – When enabled, inverts the colors in the final result.

Invert Alpha –  Inverts the alpha channel if Invert is also enabled.

Color Mult – Corrects the color of the texture by multiplying the color values in the texture with the color values specified here. 

Color Offset – Corrects the texture's color by adding the color values specified here to the color values of the texture. 

Alpha Mult – A multiplier for the Alpha value.

Alpha Offset – Controls the offset of the Alpha value.

No UVs Color – Specifies a default color used for polygons with no valid UVs. In case the map is not tiled, specifies a default color that is used outside the texture square.  

UV Noise Phase – Specifies the UV noise phase.

Color 1 – Specifies a color to be used when no node is connected to the Color 1 socket.

Color 2 – Specifies a color to be used when no node is connected to the Color 2 socket.

Grain Size – Controls the size of the fine grain features. 

Diffusion – Lower values make the resulting texture sharper, while higher values blur the texture details more.

Mix Ratio – Controls the mix between Color 1 and Color 2.