> I've played with the factories example and I can see that it's
> returning a subclass of the nodeType. This is fine but it does mean
> any isinstance calls will need to be replaced with issubclass instead.
I'm not sure I see what you mean.... what isinstance calls would need
to be replaced with issubclass? The idea is that you would use the
returned class as you would any other pynode class... Transform,
Locator, etc. Instances of that registered subclass would be
automatically returned by PyNode('nodeOfYourType') when it met the
conditions you specify with with _isVirtual
For instance, suppose you did something like:
import pymel.internal.factories as factories
class DragonLocator(Locator):
"""
Very handy subclass of Locator used for identifying where Dragons be.
"""
@classmethod
def _isVirtual(cls, obj, name):
return name.endswith("Dragons")
factories.registerVirtualClass( DragonLocator, nameRequired=True )
newNode = createNode('locator', name='HereBeDragons')
isinstance(newNode, DragonLocator)
...the final 'isinstance' will return True.
> Do you think it's wise to register virtual methods onto a base class
> instead of using the __new__ method to return a subclass?
>
> In which case perhaps factories.registerVirtualMethods([funcPoint,])
> might be acceptable?
...I may be misinterpreting what you mean - but if you're asking for a
way to add
methods onto, say, the 'regular' Locator class, then no, I don't think
we'll be providing
support for that, for two reasons:
1) It's already easy to do that, if that's what you want to do - just
'monkey patch' the
base class in the sort of way Ofer was talking about.
2) The virtual subclassing is a much more powerful method of extending
pymel, as it
allows for customized differentiation and behavior.
- Paul
> -Dave
>
> On Fri, Jul 2, 2010 at 9:26 AM, David Moulder <[email protected]>
> wrote:
>> I'll try to have a look at that today and get some feedback to you.
>> Ofer example is also interesting too. So I'll look into it as well.
>> Ofer, How are you wrapping PyMel then, Are you creating 1 module that
>> does all the monkey patching? Or have you done something more complex?
>>
>> -Dave
>>
>> On Thu, Jul 1, 2010 at 10:24 PM, Paul Molodowitch <[email protected]> wrote:
>>> It sounds like factories.registerVirtualClass should do what you
>>> need... I guess you already saw the example, so that should explain
>>> how it's used. The only word of warning is that we consider it an
>>> 'experimental' feature - I've used it before, and it worked, but I
>>> haven't used it recently, or ever really tested it extensively.
>>>
>>> That said, though, we'd love for more people to try it out, and put it
>>> through it's paces.
>>>
>>> - Paul
>>>
>>> On Thu, Jul 1, 2010 at 9:49 AM, thirstydevil <[email protected]>
>>> wrote:
>>>> Salute.
>>>>
>>>> Here at eurocom we've been debating how to design our python package
>>>> with development with pymel in mind.
>>>>
>>>> As we're becoming better OO python programmers we're using pymel more
>>>> and more. Leaving our old MEL libraries behind and slowly converting
>>>> or writing our pipeline in python with pymel.
>>>>
>>>> We've created our own package that use's pymel. The design of that
>>>> package is something that we've been debating recently in our
>>>> department. One of the main discussions is how to extend a pymel base
>>>> class without sub-classing. Because:- Where do we subclass in our
>>>> package design or even should we subclass? What do we do when we want
>>>> our subclass to always be returned by pymel?
>>>>
>>>> One of our more senior programmers has suggested a extension system
>>>> for pymel where by a PyNode would bind extension methods to it's
>>>> respective PyNode class from an extensions module.
>>>>
>>>> def isSelected(self):
>>>> import maya.cmds as cmds
>>>> return self.longName() in cmds.ls(sl=True,l=True)
>>>>
>>>> A = pCore.selected()[0]
>>>> meth = types.MethodType(isSelected, A, A.__class__)
>>>> A.isSelected = meth
>>>> A.isSelected()
>>>>
>>>> I like the idea and was wondering how other's have integrated PyMel
>>>> into their studio Libs and how they handle their package design with
>>>> pymel in mind. As sometime the line between our pipeline package and
>>>> extending pymel is blurred. Which is why the pymel extension system
>>>> came to mind.
>>>>
>>>> Looking at the customClasses example I was wondering if we can already
>>>> do this with the factories module?
>>>>
>>>> -Dave
>>>>
>>>>
>>>> --
>>>> http://groups.google.com/group/python_inside_maya
>>>
>>> --
>>> http://groups.google.com/group/python_inside_maya
>>>
>>
>>
>>
>> --
>> David Moulder
>> http://www.google.com/profiles/squish3d
>>
>
>
>
> --
> David Moulder
> http://www.google.com/profiles/squish3d
>
> --
> http://groups.google.com/group/python_inside_maya
--
http://groups.google.com/group/python_inside_maya
