Maniphest T86736

Export / Import .obj file with Principled Transmission parameter does not work
Closed, ResolvedBUG
Actions

Assigned To
Aras Pranckevicius (aras_p)
Authored By
Sebastian Feistl (sebastianfeistl)
Mar 19 2021, 12:16 PM
Tags
  • Add-ons (BF-Blender)
  • Import/Export
Subscribers
Germano Cavalcante (mano-wii)
Sebastian Feistl (sebastianfeistl)

Description

System Information
Operating system: Windows-10-10.0.19041-SP0 64 Bits
Graphics card: GeForce RTX 3070/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 461.09

Blender Version
Broken: version: 2.91.0, branch: master, commit date: 2020-11-25 08:34, hash: rB0f45cab862b8
Worked: (newest version of Blender that worked as expected)
Also tested with Blender 2.91.2 and 2.83.12

Addon Information
Name: Wavefront OBJ format (3, 8, 1)
Author: Campbell Barton, Bastien Montagne

Short description of error
Exporting an .obj file with a Principled material that has a Transmission value set is not working as expected. Re-importing the object will automatically set the Transmission parameter back to 0.

According to the documentation Importing & Exporting shader nodes should support the Transmission parameter of the Principled node.
However, the Transmission parameter value does not seem to be included in the export or Blender fails to import the property.

Exact steps for others to reproduce the error

  • create an object with a Principled shader node
  • set the Transmission parameter to anything else than 0.
  • Export the model as .obj and re-import it in a fresh Blender file.

Expected result: The Transmission value is the same as defined before the export.
Actual result: The Transmission value is 0.

Revisions and Commits

rB Blender
rBa99a62231e04 obj: implement support for PBR .mtl extensions

Related Objects

Event Timeline

Sebastian Feistl (sebastianfeistl) created this task.Mar 19 2021, 12:16 PM
Germano Cavalcante (mano-wii) changed the task status from Needs Triage to Confirmed.Mar 22 2021, 7:15 PM
Germano Cavalcante (mano-wii) updated the task description.
Germano Cavalcante (mano-wii) edited projects, added Add-ons (BF-Blender), Import/Export; removed BF Blender.
Germano Cavalcante (mano-wii) changed the subtype of this task from "Report" to "Bug".
Germano Cavalcante (mano-wii) added a subscriber: Germano Cavalcante (mano-wii).

I can confirm. In fact, the result is inconsistent with the information in the manual.

Germano Cavalcante (mano-wii) updated the task description.Mar 22 2021, 7:16 PM
Aras Pranckevicius (aras_p) mentioned this in T101029: OBJ: support PBR extensions in import/export.Sep 13 2022, 10:15 AM
Aras Pranckevicius (aras_p) closed this task as Resolved by committing rBa99a62231e04: obj: implement support for PBR .mtl extensions.Sep 13 2022, 2:04 PM
Aras Pranckevicius (aras_p) claimed this task.
Aras Pranckevicius (aras_p) added a commit: rBa99a62231e04: obj: implement support for PBR .mtl extensions.