In the tutorial Multi Layered Painting in Blender 2.72 at 36:50 a Photoshop file was used directly as an image texture.
Can that be done with a Gimp file?
Any image editing program that can produce images can be used to make textures for Blender.
Here are the image formats supported by Blender :
http://wiki.blender.org/index.php/Doc:2.6/Manual/Data_System/Files/Formats
And maybe more with addons.
Using a Gimp xcf file in the texture slot does not work for me. It works for Photoshop files, but when I try a xcf file, I get the magenta ‘no texture’ color. So my question is: does Blender support Gimp xcf files as it does Photoshop psd files in the texture slot?
Like this:
No while Blender support PSD formate native to Photoshop, it does not support the XCF format native to Gimp by default (link to supported formats do not include XCF), you need to use another format, saving your Gimp image into PNG or any supported format will give no problem to a Gimp -> Blender workflow.
you can use psd files in Gimp. The only difference is to export instead of save.
So I still have to do the extra export step each time I edit the file. The only way to use psd files directly without the extra step of exporting is to use Photoshop, right?
There’s no extra step if you use a format that isn’t XCF.
At first, instead File -> Save As , you just do File -> Export then choose the format you want
Once you have saved the image in the format you want, after further modification all you will have to do is click File -> Export to Nameofexistingfile (or just press CTRL+E ) instead of File -> Save , and it will automatically update your changes .
That’s what I have been doing. But it takes longer to export to png, I guess because it is compressing the file. Then I have to press Alt-R in Blender to update. No big deal.
Does anyone know why Blender does not directly support XCF file? Is it because some technical limitation? Are the specifications fuzzy and incomplete? or just have no interest?
https://github.com/goblin/gimp/blob/master/devel-docs/xcf.txt
I remember reading that the gimp devs didn’t wanted other application to support XCF type of files.
No idea why.
edit : found it again, thanks to the archives :
http://web.archive.org/web/20110524034732/http://lists.xcf.berkeley.edu/lists/gimp-developer/2003-February/008106.html
That said, when i look at the date, it’s more than 10 years ago, things and reasonning have probably changed in the gimp dev team, still i wonder if there’s any application that have XCF support out of Gimp now ?
edit 2 : here they are
Some i use and didn’t even noticed they have XCF import 
So the reasonning have indeed changed in the gimp devteam, but no idea why Blender does not import it (there was an addon that batch convert xcf layers into other format though not sure it works in current version) if other applications can
edit 3 :
according to wikipedia, that +10 years old thing must still be valid now :
The use of XCF as a data interchange format is not recommended by the GIMP developers, since the format reflects the GIMP’s internal data structures, and there may be minor format changes in future versions. A collaborative effort between the GIMP developers and Krita developers is underway to design a raster file format called OpenRaster, modelled on the OpenDocument format, for use in both applications in a future version.
This still works on latest Blender build http://wiki.blender.org/index.php/Extensions:2.6/Py/Scripts/Import-Export/GIMPImageToScene
Thanks Sanctuary and eppo.
In Linux, Krita and Gwenview can open xcf files. Krita opened it as layers, Gwenview shows the visible result. I do not know if they can directly read the file or if they do an intermediate conversion. Anyway, the important thing would be that Blender just can recognize the resulting image as Gwenview, right?
I am going to research about OpenRaster and see if it is still in the plans.
The only thing with import xcf addon is layers in Gimp need to be named properly and this does not translate to Cycles nodes automagically. Layers are separated into pngs by import script calls to mentioned on wiki page software - it is not direct use of xcf.
There is another addon which does allow to paint in both Blender and Gimp and changes to the image are passed other direction in almost “real time” (it’s scheduled by software but it looks as if that was realtime update).
Of course looking at the video PS workflow looks more elegant but i think Gimp can do just fine.