From: Claude Marche <Claude.Marche at lri.fr>
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Date: Wed, 9 Jul 2003 09:34:41 +0200
To: Jacques Garrigue <garrigue at kurims.kyoto-u.ac.jp>
Cc: stalkern2 at tin.it, lablgtk at kaba.or.jp
Subject: Re: animation: pixmap transparency?
In-Reply-To: <20030709092440G.garrigue at kurims.kyoto-u.ac.jp>
References: <200307080926.20760.stalkern2 at tin.it>
	<200307081555.38754.stalkern2@tin.it>
	<16138.54573.314788.280376@mailhost.lri.fr>
	<20030709092440G.garrigue@kurims.kyoto-u.ac.jp>
Sender: Claude Marche <Claude.Marche at lri.fr>


An additional remark: the following remark about gc:set_clip_mask
without argument is for gtk 1.2, and it seems that it does not work
the same with gtk 2... I have no idea how to unset clipping in gtk 2 !


>>>>> "Jacques" == Jacques Garrigue <garrigue@kurims.kyoto-u.ac.jp> writes:

    Jacques> From: Claude Marche <Claude.Marche@lri.fr>
    >> Hi Ernesto,
    >> 
    >> I think you should deactivate the clip mask before drawing your
    >> background. May be such a possibility is missing in lablgtk: directly
    >> in C, one may call Gdk_GC::set_clip_mask without argument to unset the
    >> clip mask, but I see no way to call it without argument from lablgtk. 
    >> 
    >> lablgtk maintainers, in ideas ?

    Jacques> You're damn right. This is indeed a stupid oversight.
    Jacques> The only workaround I see is to use another GC.
    Jacques> If you are using a GDraw.pixmap, this can be done by
    Jacques>   let pixmap2 = new GDraw.pixmap pixmap#pixmap ?mask:pixmap#mask
    Jacques> This way you can use two GCs: one with no clip mask, and the oter with
    Jacques> a clip mask you can change as needed.

    Jacques> I'm not sure how this should be fixed in the library.
    Jacques> One way it to make the argument to #set_clip_mask an option, but this
    Jacques> is incompatible, and not so nice.
    Jacques> Another idea would to add a #new_gc method, which would return a new
    Jacques> object with a different GC. That is, the above workaround would become
    Jacques>   let pixmap2 = pixmap#new_gc
    Jacques> This looks conceptually cleaner to me.

    Jacques>      Jacques

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