Re: Clipboard improvements, II

[Hans Breuer <Hans Breuer org>]

At 04:40 25.05.04, James Henstridge wrote:
> On 25/05/2004 6:38 AM, Hans Breuer wrote:
>
> > But it still does not support copying image via Clipboard, or di I miss 
> > this? I should have been more clear with what I would like to be able to do :
> >
> > - copy images to clipboard via cross-platform gtk/gdk code (could replace 
> > my winclipboard plug-in delivered with Gimp)
> >
> > - copy vector data to Clipboard (one of the major drawbacks of Dia - at 
> > least on windoze - is it's diability to just copy some stuff and paste it 
> > into say word)
>
> Under X, the contents of a selection is represented as an array of 8-bit, 
> 16-bit or 32-bit quantities (the last two are provided to allow transfer 
> of 16-bit and 32-bit quantities between clients with different endians).
>
> An image or vector diagram can be represented as binary data, so 
> transferring it as a selection is no more difficult than transferring 
> text.  It is just necessary for the two end points to agree on a target name.
>
> To get interoperability with existing apps under Windows, you would need 
> to know the target names that native apps use, and the format they 
> transfer data in.  If there was a GtkClipboard API for "copy this pixbuf", 
> then the Windows version would probably want to advertise the data in the 
> appropriate well known forms.

The problem is not to "advertise the data in the appropriate well known 
forms" (It is already solved by the winclipboard plug-in". Problem is that 
this kind of stuff is completely missing in the GtkClipboard API.

> > > From a brief look at the OLE clipboard docs on MSDN, it doesn't look 
> > > like there is that big a difference in how the two act.  Mozilla has a 
> > > cross platform API with implementations for win32 and X clipboard, so 
> > > it must be possible ...
> >
> > Yeah, obviously it is possible on win32 - even without OLE. The 
> > Clipboard  API works with shared memory (i.e. GlobalAlloc see 
> > gimp/plug-ins/common/winclipboard.c). But on X it appears to be either so 
> > complicated or so unusual to do/want this, that nobody bothers to 
> > implement it ...
>
> My point is that Mozilla uses the OLE clipboard, which is quite similar to 
> the X clipboard (advertise supported flavours/targets on copy, delay the 
> rendering of data and transfer until paste).  The relevant files 
> implementing Mozilla's Windows clipboard support are here:
>    http://lxr.mozilla.org/mozilla/source/widget/src/windows/nsClipboard.cpp
>    http://lxr.mozilla.org/mozilla/source/widget/src/windows/nsDataObj.cpp

Thanks for the pointers - but I still don't get why you insist on showing 
me how it is done on windoze. My point is that there apparently is no 
working standard on the X clipboard side.
BTW: I've tried to copy an image from Mozilla (Phoenix 0.5) to the windoze 
clipboard. The only thing I ve got in the Clipboard was the alternate text ...

Doing the same from "the browser which should not be named" and pasting 
into The Gimp via File/Acquire/From Clipboard (my clipboard plug-in;) 
simply works.

Thanks,
        Hans

-------- Hans "at" Breuer "dot" Org -----------
Tell me what you need, and I'll tell you how to
get along without it.                -- Dilbert