Re: [Pyobjc-dev] VTK bindings

[Carlos P. <ca...@ci...>]

On Dec 2, 2003, at 1:13 PM, Bob Ippolito wrote:

>
> On Dec 2, 2003, at 12:38 PM, Ronald Oussoren wrote:
>
>>
>> On 2 dec 2003, at 16:23, b.bum wrote:
>>
>>> On Dec 2, 2003, at 1:12 AM, Carlos Phillips wrote:
>>>> 2003-12-02 03:30:46.165 Simple1[1541] PyObjCPointer created: at  
>>>> 0x6d16080 of type  
>>>> {vtkRenderer={?={?={?=^^?i}C{vtkTimeStamp=^^? 
>>>> L}^{vtkSubjectHelper}}^{vtkAssemblyPath}^{vtkPropCollection}iIff^{vt 
>>>> kPropCollection}^{vtkActor2DCollection}^{vtkWindow}[3f][4f][2f][2f][ 
>>>> 2f][2i][2i][3f][3f][4f]}^{vtkCamera}^{vtkLight}^{vtkLightCollection} 
>>>> ^{vtkCullerCollection}^{vtkActorCollection}^{vtkVolumeCollection}[3f 
>>>> ]^{vtkRenderWindow}ffiii*{vtkTimeStamp=^^? 
>>>> L}fii^^{vtkProp}i^^{vtkAssemblyPath}iii[6f]f}8@0:4
>>>
>>> Like Bob said, once a PyObjCPointer is created, you are generally  
>>> out of luck.  PyObjC transparently bridged Objective-C.  In this  
>>> case, you are asking it to transparently bridge a relatively complex  
>>> C data type.
>>
>> The problem is that PyObjCPointer is a not really a wrapped pointer,  
>> when the PyObjCPointer object is created the value pointed-to is  
>> copied into an internal buffer. Most of the time that doesn't work,  
>> vtkRenderer is probably a C++ class and the copied value is invalid.
>>
>> I'll put creation of a real pointer wrapper on my todo-list, a  
>> generic version of the types used to wrapped some other pointer types  
>> (see pointer-support.m).
>>
>> Is VTK itself wrapped? If so, you could use the functions in  
>> pointer-support.m to convert vtkRenderer* to the Python wrapper from  
>> the VTK wrapper.
>
> VTK itself does have python wrappers.. they probably work on OS X by  
> now, but there were problems last time I tried (a long while ago, due  
> to linking issues).
>
> -bob

The VTK python wrapper now works quite well. In fact I have quite a bit  
of python VTK code which runs from the command line. I looked through  
pointer-support.m but was unable to determine how I should use it to  
leverage this fact. All the C++ classes which show up in the interface  
have a wrapped python equivalent.

Carlos