Re: [newbie] How to plot to drawing_area

[Roland Smith <rsmith xs4all nl>]

On Sun, 2 Feb 2003 12:23:03 -0300
"Individual . ." <individual@mi.cl> wrote:

> 
> On Sunday, February 2, 2003, at 09:57 AM, Roland Smith wrote:
> >
> > Plotting pixel by pixel is _slow_. It's better to use GdkRGB, e.g. 
> > using
> > gdk_draw_rgb_image(). What you have to do is read from the png file to 
> > a buffer
> > containing an array of rgb values. This is then drawn to a drawable. 
> > See the
> > example in the GDK manual.
> >
> 
> Ah! yes, speed is important.
> 
> I shall look at that example. I've also started learning about Xlib and 
> making a window directly, bypassing Gtk, and I seem to be close to 
> achieving what I want. That said, I really don't know if what I am 
> doing is at all efficient.

I've used Xlib and Athena before switching to GTK+, and IMHO it isn't pretty.
:-( Especially if you want it to work on all available colordepths etc.

For me, I would only use Xlib if I was on a platform that was slow or very
resource constrained, and if a proper GUI was not necessary, i.e. you just want
to show a picture or movie.

Roland
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