Tag: Arnold4

PBR Texture Convert tool for Mari

jarka chalásováLeave a comment

These two Mari gizmo tools are made for converting textures between three different texturing workflows (metalness, specular, Arnold4)

Download links:
Metalness (PBR) to Specular (PBR) texturing workflow
Metalness (PBR) to Arnol4 (ai standard) texturing workflow

Created in Mari 4.1. using ExtensionPack 4R2

Basic principle is described on the picture below:

GizmoMtlToSpc_01

  1. Install gizmos by copying downloaded files into Mari gizmo folder that is usually here:
    On Windows: MY_DOCUMENTS / MARI / GIZMOS
    On Mac: ~ / MARI / GIZMOS
    On Linux: ~ / MARI / GIZMOS
    Or any Folder Path you specified for Gizmos via the MARI_GIZMO_PATH Environment
  2. plug your metalness textures.
  3. Switch between outputs in the node properties.

Metalness (PBR) workflow

This PBR workflow is suitable for Arnold5 or Mantra renderers.

Metalness wf texture set:

BASE COLOR
RGB – Linear
Contains albedo color for dielectrics and reflectance value for metals.
Derived from real-world measured data

ROUGHNESS
Grayscale – Linear
black = smooth, white = rough

METALNESS
Grayscale – Linear
black = dielectric, white = raw metal

Specular (PBR) workflow

This worflow is also PBR and allows you to have better control over your specular values for dielectrics.

Specular wf texture set:

DIFFUSE
RGB – Linear
Contains only albedo color no reflectance value.
Albedo color for dielectrics is derived form real-world measured data
Metals have no albedo color, use 100% black.

SPECULAR
RGB – Linear
Contains reflectance value for metals and dielectrics.
Values are derived from real-world measured data.

GLOSSINESS
Grayscale – Linear
black = rough, white = smooth

Arnold4 (ai standard) workflow

This workflow is not PBR but you can easily convert your PBR metalness workflow textures (Mari,Substance) and convert them using Mari texture convert gizmo into required output for Arnold4 renderer.

Arnold4 texture set:

DIFFUSE
RGB – sRGB
Contains only albedo color for both, dielectrics and metals, no reflectance value.
Albedo color for dielectrics is derived from real-world measured data, metals had no albedo color (use 100% black).

SPECULAR
RGB – sRGB
Contains only reflectance value for metals derived from real-world measured data. For dielectric is specular value in this texture set to 100% white and is being determined by the fresnel texture (below)

ROUGHNESS 
Grayscale – Linear
black = smooth, white = rough

FRESNEL
Contains fresnel (F0 reflectance) value for dielectrics:
Linear = 0.04, sRGB = 59/4%
metals = 100% white