COLLADA exporter breaks UV coordinates #38322

New Issue

Mark Raynsford · 2014-01-22T16:13:02+01:00

Mark Raynsford commented

2014-01-22 16:13:02 +01:00

System Information
Linux viper 3.12.7-1-ARCH #1 SMP PREEMPT Fri Jan 10 08:50:35 CET 2014 x86_64 GNU/Linux
ATI Radeon 4870
OpenGL vendor string: X.Org
OpenGL renderer string: Gallium 0.4 on AMD RV730
OpenGL core profile version string: 3.1 (Core Profile) Mesa 10.0.2
OpenGL core profile shading language version string: 1.40
OpenGL core profile context flags: (none)
OpenGL core profile extensions:
OpenGL version string: 3.0 Mesa 10.0.2
OpenGL shading language version string: 1.30
OpenGL context flags: (none)
OpenGL extensions:

Blender Version
Broken: 2.69 5cd3212

Short description of error
COLLADA exporter appears to corrupt UV coordinates when exporting a mesh.

Exact steps for others to reproduce the error

See the blend file at http://waste.io7m.com/2014/01/22/mainframe.blend

The bug report form demands that I "drag and drop" a file onto it, but I'm not using a window manager or OS that has a desktop.

Observe the model, note the back of the model as shown in the image: http://waste.io7m.com/2014/01/22/back0.png
Export the given blend to COLLADA, ensuring that triangulation is enabled (so that the resulting mesh contains no quads).
Import the exported mesh.
For whatever reason, the imported mesh doesn't have a texture assigned, so assign the original image (add a texture, set the coordinates to the imported UV map):

http://waste.io7m.com/2014/01/22/mainframe.png

Observe the back of the imported model, as shown in the image:

http://waste.io7m.com/2014/01/22/back1.png

**System Information** Linux viper 3.12.7-1-ARCH #1 SMP PREEMPT Fri Jan 10 08:50:35 CET 2014 x86_64 GNU/Linux ATI Radeon 4870 OpenGL vendor string: X.Org OpenGL renderer string: Gallium 0.4 on AMD RV730 OpenGL core profile version string: 3.1 (Core Profile) Mesa 10.0.2 OpenGL core profile shading language version string: 1.40 OpenGL core profile context flags: (none) OpenGL core profile extensions: OpenGL version string: 3.0 Mesa 10.0.2 OpenGL shading language version string: 1.30 OpenGL context flags: (none) OpenGL extensions: **Blender Version** Broken: 2.69 5cd3212 **Short description of error** COLLADA exporter appears to corrupt UV coordinates when exporting a mesh. **Exact steps for others to reproduce the error** See the blend file at http://waste.io7m.com/2014/01/22/mainframe.blend The bug report form demands that I "drag and drop" a file onto it, but I'm not using a window manager or OS that has a desktop. 1. Observe the model, note the back of the model as shown in the image: http://waste.io7m.com/2014/01/22/back0.png 2. Export the given blend to COLLADA, ensuring that triangulation is enabled (so that the resulting mesh contains no quads). 3. Import the exported mesh. 4. For whatever reason, the imported mesh doesn't have a texture assigned, so assign the original image (add a texture, set the coordinates to the imported UV map): http://waste.io7m.com/2014/01/22/mainframe.png 5. Observe the back of the imported model, as shown in the image: http://waste.io7m.com/2014/01/22/back1.png

Mark Raynsford commented

2014-01-22 16:13:02 +01:00

Changed status to: 'Open'

Mark Raynsford commented

2014-01-22 16:13:02 +01:00

Added subscriber: @io7m

Brecht Van Lommel commented

2014-01-23 16:13:04 +01:00

Added subscriber: @GaiaClary

Saurabh Wankhade commented

2014-01-23 18:52:16 +01:00

Added subscriber: @SaurabhWankhade

Saurabh Wankhade commented

2014-01-23 18:52:16 +01:00

Did you use the Texture options ?

Did you use the Texture options ? ![Capture.PNG](https://archive.blender.org/developer/F74258/Capture.PNG)

Mark Raynsford commented

2014-01-23 18:56:28 +01:00

Ah, yes, forgot to select those. They don't prevent the UV coordinates from being corrupted, though.

Saurabh Wankhade commented

2014-01-23 19:16:20 +01:00

What do you mean by They don't prevent the UV coordinates from being corrupted??
The blend file provided does not contain textures..

What do you mean by **They don't prevent the UV coordinates from being corrupted**?? The blend file provided does not contain textures..

Gaia Clary commented

2014-01-23 19:39:10 +01:00

I can confirm there is an error. I tracked it down to a broken triangulation.
I am running a blender version from 22.1.2014 (72d3c50)

I could verify that it is the blender internal triangulation that fails here and not the collada exporter.

here is the proof:

Open the example file
go to edit mode
in UV editor assign a new uv grid image
select all faces
Mesh -> Faces -> Triangulate faces

The resulting triangulation breaks the texture:

Assigning this to Campbel...

Regarding the assigning of the texture to the mesh there is an inconvenience here with
the naming of the textures upon import. I will look into this to make this more user friendly.

I can confirm there is an error. I tracked it down to a broken triangulation. I am running a blender version from 22.1.2014 (72d3c50) I could verify that it is the blender internal triangulation that fails here and not the collada exporter. here is the proof: - Open the example file - go to edit mode - in UV editor assign a new uv grid image - select all faces - Mesh -> Faces -> Triangulate faces The resulting triangulation breaks the texture: ![Image6.png](https://archive.blender.org/developer/F74311/Image6.png) Assigning this to Campbel... Regarding the assigning of the texture to the mesh there is an inconvenience here with the naming of the textures upon import. I will look into this to make this more user friendly.

Campbell Barton was assigned by Gaia Clary

2014-01-23 19:40:57 +01:00

Gaia Clary commented

2014-01-23 19:40:57 +01:00

Added subscriber: @ideasman42

Mark Raynsford commented

2014-01-23 19:50:25 +01:00

Apologies, I didn't realize that textures weren't included in blend files. Is there some way to do this, for future reference?

Gaia Clary commented

2014-01-23 19:55:53 +01:00

File -> External data -> Pack All into .blend

Saurabh Wankhade commented

2014-01-23 19:56:32 +01:00

File->External Data->Pack into .blend file

Campbell Barton commented

2014-01-29 11:37:47 +01:00

Changed status from 'Open' to: 'Archived'

Campbell Barton closed this issue

2014-01-29 11:37:47 +01:00

Campbell Barton commented

2014-01-29 11:37:47 +01:00

Checked the geometry, theres some zero area sides of the ngons you dont notice until triangulating.

this is caused by odd geometry and not a bug. closing.

Checked the geometry, theres some zero area sides of the ngons you dont notice until triangulating. this is caused by odd geometry and not a bug. closing.

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COLLADA exporter breaks UV coordinates #38322