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This postprocess material allows you to create an effect of a reflective wet surface, with water flowing down it. (See how to apply a postprocess material to the selected surface).

The material is mapped only along the X and Y axes. If a surface is not slanted to any side and completely flat, there will be no water flow on it (only reflection).

post_filter_wet postprocess material

Wet material postprocess


GUI nameXML nameDescriptionChannels
Normalnormal A normal map that controls the flow of the water stream down the surface. RG with two components of a normal. The third component is calculated from the stored components.
Reflectionreflection Static reflection cube map used for wet surfaces. RGBA


Base Parameters

GUI nameXML nameDescription
Normal transformnormal_transform Coordinate transformation for the normal texture.
  • The 1-st and the 2-nd vector components scale texture coordinates by the X and Y axis respectively.
  • The 3-rd and the 4-th vector components specify an offset by X and Y respectively.
    • To increase/decrease the speed of water flowing down, increase/decrease the multiplier for time in the 4th vector component.
    • To add slant movement (i.e. to offset along X axis as well), specify time in the 3rd vector component.
Normal thresholdnormal_threshold Threshold for interacting with normals of the mesh surface. It controls if the water does not flow over bottom surfaces (with negative normals along the Z axis).
  • By the minimum value of 0, water flows down all surfaces, no matter what normals they have.
  • By the higher value, the wet postprocess material is not applied for bottom surfaces that face down.
Normal threshold = 0 (all surfaces are wet)
Normal threshold = 2 (surfaces that face down are not wet)
Reflection distancereflection_distance Distance in units up to which no wet process is rendered on surfaces. This option allows to optimize the performance when using the wet postprocess.

Reflection Parameters

GUI nameXML nameDescription
Normalreflection_normal Multiplier for wet texture normals. It controls the intensity of water flow according to the wet material normal map.
  • By the minimum value of 0, no water flow is rendered (wet normals have no influence on the final image).
  • The higher value, the higher the wet normal map influence and the more visible the water flow is.
Normal = 0 (no water flow)
Normal = 4
Colorreflection_color Color multiplier for wet surfaces.
  • White color means no color transformation for wet surfaces.
Scalereflection_scale Multiplier for wet Color.
  • The higher the value, the brighter the color is.

Shading Parameters

GUI nameXML nameDescription
Fresnel biasfresnel_bias Coefficient that allows to compensate for the Fresnel effect. It sets the minimum necessary reflectance level (i.e. restores reflections to be seen at all viewing angles).
  • By the minimum value of 0, there is no compensation for Fresnel power.
  • Increasing the value leads to more prominent reflections.
  • By the maximum value of 1, reflections are at their maximum and the Fresnel power parameter does not influence the rendered image.
Fresnel powerfresnel_power Factor to scale Fresnel effect that defines the amount of reflectance depending on the viewing angle:
  • Low values provide good reflectance even at a large viewing angles.
  • High values provide the reflectance only at a small viewing angle. When looking at a large viewing angle, from above, there are no reflections rendered.
If the Fresnel bias equals 1, Fresnel power does not apply.


GUI nameXML nameDescription
Maskmask Color mask for the materials' auxiliary color. See how to use it as a mask to apply a postprocess only to the selected materials.
Last update: 2017-07-03