[PyQt] converting SWIG objects to SIP objects

[Phil Thompson]

On Wed, 01 Sep 2010 11:00:30 -0400, Blaine Bell
<blaine.bell at schrodinger.com> wrote:
> I was able to write a SIP function that takes a SWIG object, converts it

> to a SIP object, as well as a function that converts a SIP object back 
> to a SWIG object:
> 
> The object I have implemented in SIP and SWIG is called "ChmMol":
> 
> ChmMol *convertChmMoltoSIP(SIP_PYOBJECT);
> %MethodCode
>     if (!SWIGTYPE_p_ChmMol){
>         SWIG_init();
>     }
>     if ((SWIG_ConvertPtr(a0,(void **) &sipRes, SWIGTYPE_p_ChmMol, 0 )) 
> == -1) return NULL;
> %End
> SIP_PYOBJECT convertChmMoltoSWIG(ChmMol *);
> %MethodCode
>     if (!SWIGTYPE_p_ChmMol){
>         SWIG_init();
>     }
>     sipRes = SWIG_NewPointerObj(a0, SWIGTYPE_p_ChmMol, 0);
> %End
> 
> 
> In order to do this, I needed to include the c++ file that was generated

> by swig executable running on the SWIG .i file.  Including that c++ file

> (in the "%ModuleCode") instantiates an entirely new SWIG dictionary 
> inside my SIP DLL that needs to be initialized (hence, the SWIG_init() 
> call).
> 
> My question to the SIP experts: is there a way to allow SIP to allow 
> SWIG or SIP objects as arguments that have a specific type?

For a specific type you could define it to SIP as a %MappedType and
implement conversion code that called the SWIG API.

> Is there a 
> Directive or Annotation that allows me to write a conversion, so I can 
> override the conversion from the Python object to C++ object for each
type?

No, although I'm not sure I understand the question.

Phil