Re: Optimization question

[Dov Grobgeld <dov imagic weizmann ac il>]

On Wed, Feb 06, 2002 at 09:49:53AM -0500, Daniel Carrera wrote:
> Thanks.  I am not sure that I completely follow your explanation.  Maybe
> you can help me out.
>
> > Since you are painting numbers, the fastest would be to do a prerendering
> > of all the numbers and store these in GdkPixbuf's in memory.
>
> Who do you do that? I haven't found any documentation on that.  I don't
> know how to do that.
>
> Is this what you mean?:
>
> my $number = Gtk::Gdk::ImlibImage->load_image("7.xpm")

Yes. That's the way, though I think that I would rather keep all
the pictures in one single image. This is exactly how my perl/gtk
program abc blocks works. See:

    http://imagic.weizmann.ac.il/~dov/freesw/gtk/abc-blocks/abc-blocks.html

The following is a modified version of part of its code:

     $big_card = load_image Gtk::Gdk::ImlibImage($card_name);

     my $photo = $big_card->crop_and_clone_image($x0, $y0,
                                                 $width, $height);

     $number1_img=Gnome::CanvasItem->new($canvas->root(),
                           "Gnome::CanvasImage",
                           image=>$photo,
                           x=>0,
                           y=>0,
                           width=>$width,
                           height=>$height,
                           anchor=>"nw"
                          );

You can create a gdk image like in $photo above, for each of your digits,
and store these e.g. in @digit_image .

You then create an CanvasImage for each of the numbers you want to display.
E.g. if you want to show:

     56:78

Then 5 could be shown e.g. by $number_1, 6 by $number_2, etc where
$number_1 to $number_4 are CanvasImages that you placed at their desired
positions.

You can then choose the digits to show by doing:

    $number1_img->set(image=>$digit_image[3]);

to set the image of number1_image to the image showing a "3".  

I hope this is a bit clearer than my last message.

Regards,
Dov