GLTF Exporter blender 3.2 and above flips the axis of rotation for exported camera transforms matrices #99306

New Issue

Seth · 2022-06-30T23:09:39+02:00

Seth commented

2022-06-30 23:09:39 +02:00

System Information
Operating system: Windows
Graphics card: GTX 980

Blender Version
Broken: 3.3.0, 0ea282f74620, master, 2022-06-30
Worked: 3.1.2

Short description of error

Blender's gltf exporter forces the camera to face the wrong direction on export. There is an issue when +Yup is toggled off. The issue was first observed in 3.2 and persisted in 3.3 alpha.

To test and validate the issue with the camera rotation matrix, you can export a gltf from 3.1.2 and one from 3.3 alpha and import both gltf into the same scene. This test shows an error with the gltf exporter in Blender 3.3 alpha compared to 3.1.2 as it flips in the wrong direction on import into Blender.

Exact steps for others to reproduce the error
Attached files
You can use the supplied gltf or create your own using the below steps.
blender-exporter-files.zip

Steps for creating the gltf files to validate that there is an issue with the camera flipping do to gltf exporter

Open Blender 3.1.2 (use the default generic scene).
Hit A in the viewport to select all (not really required)
File -> Export -> gltf
- gltf export settings
- Format
  - gltf Embedded(.gltf)
- Include
  - Cameras (Selected)
  - Punctual Lights (Selected)
- Transform
  - +Y Up (Toggled off)
- Geometry
  - UV (selected)
  - Normal (selected)
  - Vertex Colors (selected)
- Use the default setting for the remaining options

Name the file
- blender-3-1-2.gltf
Export gltf 2.0 with the above settings
Repeat the above steps but using Blender 3.3.0
- Name new gltf
  - blender-3-3-0.gltf
    Testing the camera issue (using your own or supplied gltf files)
Open a new scene or use the existing Blender 3.1.2 or 3.3.0 scene
- import gltf
  - blender-3-1-2.gltf
- import gltf
  blender-3-3-0.gltf

See the visual difference in imported camera direction and settings.

**System Information** Operating system: Windows Graphics card: GTX 980 **Blender Version** Broken: 3.3.0, 0ea282f74620, master, 2022-06-30 Worked: 3.1.2 **Short description of error** Blender's gltf exporter forces the camera to face the wrong direction on export. There is an issue when +Yup is toggled off. The issue was first observed in 3.2 and persisted in 3.3 alpha. To test and validate the issue with the camera rotation matrix, you can export a gltf from 3.1.2 and one from 3.3 alpha and import both gltf into the same scene. This test shows an error with the gltf exporter in Blender 3.3 alpha compared to 3.1.2 as it flips in the wrong direction on import into Blender. ![image.png](https://archive.blender.org/developer/F13244012/image.png) ![image.png](https://archive.blender.org/developer/F13244015/image.png) **Exact steps for others to reproduce the error** **Attached files** You can use the supplied gltf or create your own using the below steps. [blender-exporter-files.zip](https://archive.blender.org/developer/F13244023/blender-exporter-files.zip) **Steps for creating the gltf files to validate that there is an issue with the camera flipping do to gltf exporter** - Open Blender 3.1.2 (use the default generic scene). - Hit A in the viewport to select all (not really required) - File -> Export -> gltf - **gltf export settings** - Format - gltf Embedded(.gltf) - Include - Cameras (Selected) - Punctual Lights (Selected) - Transform - +Y Up (Toggled off) - Geometry - UV (selected) - Normal (selected) - Vertex Colors (selected) - Use the default setting for the remaining options ![image.png](https://archive.blender.org/developer/F13244025/image.png) - Name the file - blender-3-1-2.gltf - **Export gltf 2.0** with the above settings - Repeat the above steps but using Blender 3.3.0 - Name new gltf - blender-3-3-0.gltf Testing the camera issue (using your own or supplied gltf files) - Open a new scene or use the existing Blender 3.1.2 or 3.3.0 scene - import gltf - blender-3-1-2.gltf - import gltf # blender-3-3-0.gltf See the visual difference in imported camera direction and settings.

Seth commented

2022-06-30 23:09:39 +02:00

Added subscriber: @sethnykamp

Seth changed title from ~~GLTF Exporter 3.2 and above flips the axis of rotation for exported camera transforms matrices~~ to GLTF Exporter blender 3.2 and above flips the axis of rotation for exported camera transforms matrices

2022-06-30 23:11:30 +02:00

Julien Duroure commented

2022-07-01 06:23:00 +02:00

Added subscriber: @JulienDuroure

Julien Duroure self-assigned this 2022-07-01 06:23:00 +02:00

Julien Duroure commented

2022-07-01 06:23:00 +02:00

Changed status from 'Needs Triage' to: 'Confirmed'