[Bf-python] Blender -b and Scenes

[Willian Padovani Germano]

Hi Campbell,

Yes, you have a point, indeed many py functions may rely on G.scene, I 
didn't consider that in my previous reply. We still need to check the 
pointers (good practices, not just for bg mode), but creating a scene 
iff G.scene is NULL AND we're in bg mode may be a good solution in this 
case (others here: opinions?).

Anyway, please don't commit it before you email bf-committers about your 
intention. Ton and others may have important comments about this. I'd 
also suggest, if it gets accepted, that you print a msg to the console, 
informing the user that a scene was created, something like: "No scene 
available, creating an empty one.". Checking that the scene was actually 
created and assigned to G.scene is a must too, of course.

Campbell Barton wrote:
> Hey Willian,
> 
> thaught of just adding checks, and while its okay for functions that 
> directly use G.scene, there are functions that python calls that use 
> G.scene
> Also, if you cover all cases, its adds up to a fair few checks.
> 
> Just seems a simpler option to add a scene when importing Blender
> keep in mind this only effects blender when running in background mode.
> 
> would be somthing like
> if (!G.scene)
>  add_scene("Scene");
> 
> This would save us adding checks to World, Mesh, Scene? and others for 
> this 1 rare case.
> It also seems logical that when you start blender and run a script in 
> User mode you have a empty scene. so why not have 1 in background mode?
> - Cam

--
Willian