[Bf-python] Adding objects and scenes refactor

[Willian Padovani Germano]

Hi Campbell,

We do need a wiki page for this topic, I'll just reply here to a small 
issue.

Campbell Barton wrote:
> Once of the biggest problems is that Python API allows you to create an 
> object with no obdata...
> Ton was requested this be made not possible

No, that was never possible. Object.New() *always creates obdata*, 
unless you're creating an Empty, of course. The issue is with obdata, 
since NMesh.New(), Camera.New(), etc. create *obdata that is not linked 
to any object*. For this reason, the docs advise people to use:

ob = Object.New('Lamp')
obdata = ob.data

#instead of:

obdata = Lamp.New()
ob = Object.New('Lamp') # is created with obdata already
ob.link(obdata) # unlinks the original obdata

One possibility is to simply remove these obdata creation functions, but 
since there are situations where they are useful (and for backwards 
compatibility), we may just ad a new better way to create an ob+obdata 
already linked to a scene and keep this older way for those who need it.

To all: we agreed that the API for creating data (ob, obdata, scenes, 
texts, images) deserves a wiki page for discussions, once it is created 
(anyone is free to start it) and announced here, let's continue the 
discussion there.

-- 
Willian