AxF (Appearance eXchange Format)


Substance 3D Designer Supports X-Rite's Appearance eXchange Format. X-Rite describes AxF as following:

"AxF files are used to capture, store, edit, and communicate complex material characteristics throughout the digital design workflow. AxF provides a standard way to store and share all relevant appearance data – color, texture, gloss, refraction, translucency, special effects (sparkles) and reflection properties – across Product Lifecycle Management (PLM), Computer-Aided Design (CAD), and state-of-the art rendering applications."

In simpler terms, AxF files are slightly similar to Substance Packages: they contain a number of textures, extracted by X-Rite's TAC7 scanner hardware coupled with metadata that describes additional properties of a material not captured in the textures. AxF can describe a few different material models in different versions of the format, but Designer only supports SVBRDF (Spatially Varying BRDF ) materials. That means an AxF is more than just texture data: it also implies certain shading properties.

AxF files are not used as an actual single resource by Designer, some conversion is done, resulting in a few Bitmap Resources, a Substance Graph and an MDL Graph.

AxF Model compatibility

Not all AxF models are compatible, the list below shows what is and is not supported. AxF files containing models not supported by Designer, cannot be imported (the import dialog notifies you).

AxF Model

Supported?

BTF

No

SVBRDF

Yes

CPA2

No
VolumetricNo
EP GGXNo

Importing AxF Files

AxF files are imported through the Explorer window.

  • Right-Click on a package in the Explorer, choose Import > AxF
  • Select an AxF file on disk.
  • Wait for the Import AxF dialog to appear. See above if dialog returns no result.
  • Customize the dialog (choose graph name and resolution)
  • See below if any more actions are needed to view them

Fixing Opacity Issues

If an AxF file contains no opacity data, Designer will default to pure black, invisible opacity data. The 3D view will look like it is displaying nothing. This needs to be fixed first to get any visible results.

After this, the 3D view should display a representation of your material.

Viewing AxF Files

Once an AxF files is imported, you get 3 types of resources. Bitmaps are used by the Substance Graph for small conversions, then that Substance Graph is used as texture input for the MDL Graph.

To view the material in the OpenGL viewport:

  • Double Click the Substance Graph created after import.
  • Right-click empty area, choose View Outputs in 3D View.

To view a more correct representation of the material with the iRay renderer:

  • Double Click the MDL graph created after import.
  • Right-click in the MDL graph and choose Set as Material Definition in 3D View.
  • Drag the Substance Graph from the Explorer, to the 3D Viewport to set it as the input for the MDL material definition.

If you have not fixed any potential issues with the opacity channel, nothing will be visible in the 3D view. See above.

Improving AxF Files

As AxF files are fairly limited in resolution (under 2048x2048 px), there is a lot of potential to improve them with Substance tools.

Tiling can be fixed within Designer using tools in Scan Processing, procedural effects can be added, or even multiple AXF scans can be combined.

When published as SBSAR format, you can set up parameters to have more control, and use other tools such as Substance 3D Sampler to mix and modify them, or Substance 3D Painter to use your AxF files as materials when painting.