Re: [Gimp-user] Debugging register function for registration of a python plugin under Windows XP

[Ofnuts <ofnuts laposte net>]

On 15/06/14 23:45, SeldomNeedy wrote:
> Obviously, normal fault-hunting can be done via gimp.pdb.message(someMessage)
> once a plugin is successfully registered. Windows/Dockable dialogs/Error console
> is obviously very helpful once an extension is up-and-running, HOWEVER I found
> registration fairly trying and had a number of problems getting this to work
> with basically no feedback about what I might be doing wrong. Ideally, getting
> started should be the easiest part of the process, not the hardest. Thanks for
> posting the guide. I'll definitely consider using that approach in future. I
> came across an alternative which you may consider adding (though I haven't
> compared the techniques for getting error-output so I don't know which one is
> better).
>
> Anyways, for the reference of other users developing GIMP Pythonfu plugins under
> Windows, I'll repeat some information which I found very helpful when I was
> searching. At the very top of the .py file, it's can be useful to do something
> like:
>
> import sys
> sys.stderr = open("C:\\tmp\\errs.txt",'a')
>
> This will cause the python environment to show some otherwise-hidden startup and
> register-registration errors by outputting / printing them to the specified
> location. The example I saw used mode 'a' to append errors, rather than
> overwrite. Doing this allowed me to spot a mistake I was making.
>
> In addition, one can also do
>
> import sys
> sys.stout = open("C:\\"tmp\\msgs.txt",'a')
>
> if it's more convenient to receive output this way.
>
>
> > Additionally, Toolbox-prefix category is deprecated (since at least Gimp 2.6).
> you
> > should be putting your menu entry in Image-prefix category (the window
> displaying
> > the current image), or in Layers-prefix category (the right-click menu in the
> > layers list), but the latter requires your plug-in to take image and drawable
> > parameters.
> Can you link to where this deprecation is publicly documented? The information
> available on GIMP Python-fu is often out-of-date and extremely disparate, I've
> found. Even http://www.gimp.org/docs/python/ is out of date in some respects, at
> least comparing it stylistically to some examples I've seen here and elsewhere.
> It would be helpful to know what calls are deprecated or now broken between
> versions so users will have some idea of whether they're looking at an outdated
> (and possibly broken or unreliable) way of doing things.
>
> Your response also makes me wonder what of the other plugin-categories are (the
> ones that get specified in angle brackets) still work, and what their
> requirements are. An (outdated?) list of them I wrote down at some point went:
> "Toolbox", "Image", "Layers", "Channels", "Vectors", "Colormap", "Load", "Save",
> "Brushes", "Gradients", "Palettes", "Patterns" or "Buffers".
>
> Thanks!

IIRC in 2.6 you got a "Location deprecated" message in the startup 
messages (but of course you see this on Linux only :)). Anything you put 
in <Toolbox> actually went to <Image>. In 2.8 you don't get the message 
at all and the registration seems ignored.

Expect for <Image> (and, I think, <Load> and <Save>) all others correspond the menu of the dockable dialog of 
the same name.

When the object is specific to an image (Layer/Channel/Path) the 
registered function should take an image as the first parameter, and the 
relevant object type as a second one. They are automatically filled with 
the image and the object on which you right-clicked). Other menus  don't 
require any specific parameters.