kicad-developers team mailing list archive

[jean-pierre charras - INPG <jean-pierre.charras@...>]

Marius Kintel a écrit :
> On Apr 1, 2008, at 11:03 AM, emmedics4 wrote:
>
> > I can confirm that wxOR is not supported in wxMAC with CG as
> > confirms dc.cpp:1985
> > GR_COPY is enough for us now and draws all correctly.
> > I think that the correct path with CoreGraphics is the Alpha Channel
> > and also this have to
> > work with GR_COPY.
> >
>
> I have a question (maybe I just don't get it though):
> What does really GR_OR do?
> In other words: What is the expected result for OR'ing graphics with
> existing graphics?
This mode can show superimposed tracks with a transparency effect.

> As far as I understand, this is pretty much a bogus operation in all
> cases except 1-bit displays or bitmaps.
> For colored graphics, it would just OR together whatever data is
> present, with pretty random results.
If colors are well selected (depending on the binary configuration used 
in R,G,B values) , the result is good.
But it does not works very well for all colors in fact for most of cases 
the result is bad)..
This is the reason why kicad has only some colours allowed in the colors 
selection dialog
All of R,G,B values i used give good results in OR mode.
> ..or maybe it is a workaround for missing blend/alpha functionality in
> some GUI toolkits?
This is *exactly* the case.
I never used blend/alpha functionality instead of OR mode (it did not 
exists when i started kicad), but i think this is a good idea.

But moving objects still must use the XOR mode
(i am not sure full redraw of the screen when moving an object is 
useable for large and complex boards)

--
Jean-Pierre CHARRAS
Maître de conférences
Directeur d'études 2ieme année.
Génie Electrique et Informatique Industrielle 2
Institut Universitaire de Technologie 1 de Grenoble
BP 67, 38402 St Martin d'Heres Cedex

Recherche :
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