Re: setting line dash on Gnome2::Canvas

[Remco Wouts <remco wouts mpibp-frankfurt mpg de>]

Torsten Schoenfeld wrote:
> On Thu, 2006-03-16 at 18:04 -0500, zentara wrote:
>
>
> > # feeble attempt dosn't work
> > #$line1->set_dashes( {0,0xff,0,0xff} );
>
>
> As the name gdk_gc_set_dashes suggests, you need to call the set_dashes
> method on a Gtk2::Gdk::GC object:
>
>   $gc->set_dashes(0, 0xff, 0, 0xff);
>
> Unfortunately though, the "gc" struct member of Gnome2::Canvas::Line is
> not accessible via the bindings at this point -- so right now, I think
> this isn't possible.
The following hack works for me:

use Inline C => 'DATA';

Inline->init;

....<your stuff>
$canvasitem->set(dash=>main::pattern(0,10,5));

__DATA__

__C__

void pattern(SV* dashes, ... )
{
        Inline_Stack_Vars;
        int i;

        static struct dashes {
          double offset;
          int ndash;
          double *buf;
        } *dash = NULL;
        
        
        if ( dash == NULL ) {
           New(0, dash, 1, struct dashes);
           New(0, dash->buf, Inline_Stack_Items-1, double);
        } else {
           Renew(dash->buf, Inline_Stack_Items-1, double);
        }
        dash->ndash = Inline_Stack_Items-1;
        dash->offset = SvNV(Inline_Stack_Item(0));
        for ( i = 1; i < Inline_Stack_Items; i++ )
          dash->buf[i-1] = SvNV(Inline_Stack_Item(i)) > 0 ?
SvNV(Inline_Stack_Item(i)) : 1;
        Inline_Stack_Reset;
        Inline_Stack_Push(sv_2mortal(newSViv((long) dash)));
        Inline_Stack_Done;
}


-- 
remco wouts