Re: Fwd: Re: [pygame] SDL-ctypes progress

[Alex Holkner <aholkner@xxxxxxxxxxxxxx>]

Rene Dudfield wrote:

> Nums!  A new name for the group (Numpy, Numeric, Numarray) is Nums.
>
>
> +1 for polymorphism.  Although the current api is good too.
>
> You can always check the return type if you need to know its type.
> The nums are similar enough for lots of uses.  Often only one type
> will be installed on someones machine.
>
> pixels.as_nums() ?  which returns a globally registered num?  Or
> as_globally_registered_array() for a really long name.
>
> Ok, I can't think of a good name for it.
>
>
> Another option...
> Maybe instead of surf.pixels.as_something()...
>
> surf.pixels
> surf.pixels_numpy
> surf.pixels_numarray
> surf.pixels_numeric
> surf.pixels_yet_another_numeric_type_when_it_comes_up
> surf.pixels_num
>
> The pixels_num would be the globally registered type.  There would
> still be surf.pixels the same as it is now.  The globally registered
> type would be discovered and set the same way that pyopengl does.
>
> What about that?

Ok, some of this discussion is somewhat pointless: Numeric and numarray 
cannot be supported; they do not have the functionality to construct an 
array from an existing buffer (even if they do in the future, we would 
obviously be relying on a feature that doesn't exist in the majority of 
users' cases).  Note also that numpy supercedes numeric and numarray; 
according to numpy.org, "new users should start out with numpy".  By 
definition, all users of SDL-ctypes will be new users (creators of new 
projects).

So the three use cases are: accessing the buffer with slices, using 
numpy operators, or casting to some hypothetical future array package 
implementing the array interface.  The first is supported natively: 
surf.pixels[4:10] slices using ctypes.  The second, as mentioned, can be 
constructed if the application is certain numpy is installed with 
surf.pixels.as_numpy().  The last is possible, if/when ctypes exposes 
the proposed array interface, e.g.: hypothetical_array(surf.pixels).

I am definitely _not_ a fan of having to check a return type to find out 
what it is (as I write this, I realise that's exactly what I've done 
with the event functions... hmm, better think harder about that).

Alex.