IBL Terrain Shader

The terrain shader has a few modes available, with legacy support for the old styles of blending used on older tracks, as well as a newer splatterMap method.

This page gives technical definitions.  For usage guide see: PBR - Using Terrain Shader

Shader Name



Please note UV_A, UV_B, UV_C or UV_D refers to as specified in the gTexture slot in 3ds Max. There is a full explanation of this here.

Maps Configuration

  • Albedo Maps: 1,2,3 or 4. Number of Albedo Maps, use upto 4 with Splatter map blending.
  • Normal Maps: 1 or 2.

UV Control

Configure each map to use either UV_A, UV_B, UV_C, UV_D or WorldPlanar

Terrain Shader Options

  • Splatter Vertex Colour Blend: Disable, Detail or Multiply. Choose how Vertex Colour can be applied to the splatter map to configure advanced blending.
  • Unique Pattern UV: Allows the setting of unique UV options for each channel of the pattern map
  • Pattern Random Blend: Allows the over-ride of Vertex Alpha input to set random values to blend between the two pattern maps.

Translucency (Experimental)

  • Translucency: Enable or Disable Translucency on this material.
  • Invert Alb.R Mask: Use an inversion of the Albedo Red channel as a mask for the translucency. This will naturally make greener areas slightly more translucent than dry dirt.

General Configuration

  • Debug Blending: Enables blending with block colours to help debugging with blending patterns.
  • Receive Shadows: Enable or Disable receiving shadows.
  • Baked Shadows: Enable or Disabled baked shadows. With legacy modes these come from Vertex Alpha. With Splatter map these are taken from the alpha channel.



This dialogue allows the scaling of the selected UV for any maps present.


This section allows the adjustment of final output of the material. 

  • AlbedoTint
  • ReflectionAt0Angle
  • Specular: 1.0 is recommend default for most materials. For natural materials this may need reducing to around 0.5 depending on the nature of your specular maps.
  • SpecularTinting: This controls how much of the albedo colour is used to tint the specular output.
  • Roughness: Adjust overall Roughness, lower than 0.5 makes surfaces smoother. Above 0.5 makes surfaces rougher.
  • NormalIntensity: Adjust the overall strength of normal maps in the entire material.
  • NormalShadowInflunce: Adjust the amount of influnce the normal map has on shadows cast onto this surface.


This allows you to set the intensity of the normal map on a per albedo basis.


Here you can configure what blend of Normal A and Normal B is used for each albedo map.


Configure the strength of Terrain Pattern Strength, on a map basis and overall, the Mixmap Bias value, and the strength of any Splatter Map overlay.

Debug Blending

Configure the colours used when debug blending is enabled.


Configure the Power (how broad or refined the effect is) and Strength of the Translucency effect as well as setup scalars on a per albedo map basis.





Default File Types





Default File Types


albedoRoughATrueSRGB (Alpha linear)albaThe first albedo map with a roughness mask in the alpha channel.
albedoRoughBTrueSRGB (Alpha linear)albaThe second albedo map with a roughness mask in the alpha channel.
patternTrueLinearpt or mua
  • This is a linear BC5 map with two overlay patterns.
  • The first in the r channel and the second in the g channel.
  • The two are blended by vertex alpha
  • It is possible to configure the channels with unique UVW.

This is a linear map with a mixmap or height map in the red channel, this is used to blend between albedo maps.

There is also also a specular mask in the green channel.

The map is sampled at the two sets of UV resolutions and blended with a 60% bias towards the higher scaling.

albedoRoughCTrueSRGB (Alpha linear)albaThe third albedo map with a roughness mask in the alpha channel.

NormalMapA and NormalMapB are blended based on the calculated overall value from the weights set in Normal_Blends


R: Blends from AlbedoA to AlbedoB

G: Blends from the previous output to Albedo C

B: Blends from the previous output to Albedo D.

A: A baked shadow map.

albedoRoughDTrueSRGB (Alpha linear)alba

Note: At present you can not set this map in 3ds Max.

The fourth albedo map with a roughness mask in the alpha channel.


This is an overlay map that can be applied to the splatter map to add fine details to the splatter map.

The alpha channel is used as a specular mask.