Texture Atlas Error

Support Materials and Textures
1

I am using the Texture Atlas to combine UVs from multiple objects, all of which have UVs already unwrapped and laid out. To do this I am adding the objects to the atlas and then using the ‘StartManualUnwrap’ button. This is all following the CGCookie course on ‘shading a scifi helmet’.

When I do this I get the following error:

Traceback (most recent call last):
  File "C:\Program Files\Blender 
Foundation\Blender\2.78\scripts\addons\uv_texture_atlas.py", line 214, in 
execute
    group_name=group.name, unwrap=False)
  File "C:\Program Files\Blender 
Foundation\Blender\2.78\scripts\modules\bpy\ops.py", line 189, in __call__
ret = op_call(self.idname_py(), None, kw)
RuntimeError: Error: Traceback (most recent call last):
  File "C:\Program Files\Blender 
Foundation\Blender\2.78\scripts\addons\uv_texture_atlas.py", line 673, in 
execute
    bpy.ops.object.join()
  File "C:\Program Files\Blender 
Foundation\Blender\2.78\scripts\modules\bpy\ops.py", line 189, in __call__
    ret = op_call(self.idname_py(), None, kw)
RuntimeError: Operator bpy.ops.object.join.poll() failed, context is 
incorrect


location: C:\Program Files\Blender 
Foundation\Blender\2.78\scripts\modules\bpy\ops.py:189






location: <unknown location>:-1

Does anybody have an idea why this is happening?

I tested by just adding two of my objects to the atlas, rather than all of them, with the same outcome. I also tried starting a new blend file and unwrapping two cubes, combining them with the atlas and then performing the manual unwrap. This worked fine.

Thanks in advance.

2

It says “RuntimeError: Operator bpy.ops.object.join.poll() failed, context is
incorrect” so it failed to join two objects. May be they are instaces and share the same mesh data? May be they aren’t meshes at all?

3

Good idea, however when I do the simple test of adding just two objects to the atlas (which are definitely single-user mesh objects) the same error occurs, suggesting that that isn’t the problem.

Thanks

4

I worked around this by starting a brand new blend file and appending all my objects from the old file.