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gamedev:textureproperties:nonpbr_albedo

Skin Texture Property: nonpbr.metalness

Excepted Data Source1 component image
Data Range0 to 1
Default Value0
Affected ModulesGraphic
Linked Propertiesnonpbr.albedo

Description

Defines an artificial Non-PBR Metalness value. This texture property is part of Non-PBR Metalness workflow and is used together with the nonpbr.albedo texture property. These values are Non-PBR since they do not represent a single real world material properties. Instead they store color and reflectivity texture property in a merged format distributed across an albedo and a metalness texture image.

The albedo image stores color for dieletric parts of the material and a limited reflectivity for eletric parts of the material. The metalness texture is used as mask. Only for true black and white metalness image this conversion yields reasonable results. For blended values problems like white-edging can happen.

The conversion rule used is:

  • color = mix(albedo, vec3(0), metalness)
  • reflectivity = mix(vec3(0.04), albedo, metalness)

Reflectivity is limited since it maps to the range from 4% to 100% reflectance and can not represent well materials with partial eletric behavior.

These texture properties exist to allow using textures authored by tool supporting only the Non-PBR Metalness workflow as well as porting from other game engines.

The albdeo values are typically an 8 bit image with 1 color component with the data located inside the range from 0 to 1. 0 represents dieletric materials using albedo as color. 1 represents eletric materials using albedo as reflectivity. Values in between blend between these two mappings.

The default value for this texture property is 0.

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gamedev/textureproperties/nonpbr_albedo.txt · Last modified: 2022/05/03 17:37 by dragonlord