OpenEuphoria

Re: EuCom

• Posted by Matt Lewis <matthewwalkerlewis at gmail.com> Sep 25, 2005
• 462 views

Tone Škoda wrote:
> 
> Matt, I just wanted to mention that there is a problem in
> call_interface_ptr(),
> actually the problem is really in fptr.e in call_stdcall_proc():
> 
> First argument of MediaDet_WriteBitmapBits is
> double which is 8 bytes long. call_interface_ptr() expects
> that all arguments are 4 bytes long because it uses poke4().
> It should use poke() and should take another argument:
> params_sizes. We are unable to call function with parameters which are char
> (=1 byte)
> for example.
> I think that it would be simplest if it would imitate the way Euphoria dll
> calling
> functions work: define_c_func...
> As I said I found workround but future people using EuCom will probably get
> confused
> over this.
> 
> frame_pos_bytes = atom_to_float64 (frame_pos)
> retVal = call_interface_ptr (this, vtbl, MediaDet_WriteBitmapBits,
>     -- split double into two atoms.
>     bytes_to_int (frame_pos_bytes [1..4]) & bytes_to_int (frame_pos_bytes
>     [5..8])
>     & {dest_width, dest_height, dest_fname_ptr})
> 


Thanks,  I hadn't run into any functions like this before, so I didn't
really consider it.  But I'll think about how to solve this.  I don't
really like duplicating the define_c_* API, because it means I'll have to 
keep track of all that, but it may be the only way.  

Matt Lewis