[OpenLayers-Dev] [Dev] Re: Vectors in OpenLayers?
Bart van den Eijnden (OSGIS)
bartvde at osgis.nl
Thu Oct 19 03:44:12 EDT 2006
Will there also be an option to serialize the objects as GML?
Since interaction will mostly be against OGC Web Services.
Best regards,
Bart
--
Bart van den Eijnden
OSGIS, Open Source GIS
http://www.osgis.nl
--------- Oorspronkelijk bericht --------
Van: Paul Spencer <pspencer at dmsolutions.ca>
Naar: Pierre GIRAUD <bluecarto at gmail.com>
Cc: dev at openlayers.org
Onderwerp: Re: [OpenLayers-Dev] [Dev] Re: Vectors in OpenLayers?
Datum: 19/10/06 00:09
> Hi Pierre,
>
> I haven't looked at the code but I think that this will be needed in
> some sort of factory object that can create Geometry (and associated
> Shape) objects from WKT. We are a bit early for implementation
> details right now (despite the fact that I've already done a bunch of
> implementation), but when the design is finalized, we'll need this
> piece.
>
> This reminds me that Geometry objects need to be able to serialize
> themselves as WKT.
>
> Cheers
>
> Paul
>
> On 13-Oct-06, at 12:46 PM, Pierre GIRAUD wrote:
>
> > I wanna propose you some peace of code for this.
> > Hope you'll be able to have a quick look and check if I'm the good
> > way.
> >
> > I tried to follow the "factory" pattern, but I'm not sure I
> > implemented it right considering the rest of the architecture.
> >
> > Regards and nice week-end
> >
> > Pierre
> >
> > ps : this code might be useable in the current vector sandbox
> >
> > On 10/13/06, Pierre GIRAUD <bluecarto at gmail.com> wrote:
> >> I don't know if this is a needed functionnality, but it can
probably
> >> help. I was trying to think about and implement a way to add a
> >> feature
> >> by its WKT string writing.
> >>
> >> Something like :
> >>
> >> OpenLayers.Vector.WKT
> >>
> >> p4 = new OpenLayers.Vector.WKT('POINT(-40 30)');
> >>
> >> Regards
> >>
> >> Pierre
> >>
> >> On 10/13/06, Paul Spencer <pspencer at dmsolutions.ca> wrote:
> >> > Thanks Chris :)
> >> >
> >> > Performance really sucks if you add a lot of features. I
wrote a
> >> > quick loop to add a 1 degree box every 10 degrees and
brought my
> >> > firefox to a halt. Profiling reveals a number of
problematic
> >> areas,
> >> > the biggest of which is getPx (of course).
> >> >
> >> > I've done some optimization that improves performance in
this case:
> >> >
> >> > * remove the call to Pixel.add(x,y) and directly modify the
pixel
> >> > position - this was a big savings ...
> >> >
> >> > * cached px location in the Point object based on the bounds
of the
> >> > containing vectorLayer so getPx is only called when the
bounds have
> >> > actually changed.
> >> >
> >> > attached is a patch against the sandbox to incorporate these
> >> changes.
> >> >
> >> > Next steps for me are:
> >> >
> >> > * fix rendering in IE and Safari (that was the whole point
of using
> >> > excanvas)
> >> >
> >> > * further optimizations, including:
> >> >
> >> > o try caching the bounds of each vector and test for
> >> intersection
> >> > with layer bounds before rendering
> >> >
> >> > o tighten inner loops and remove deep call chains
(possibly
> >> > putting some of the pixel conversion stuff right into
convertToPx)
> >> >
> >> > o anything else you can think of
> >> >
> >> > * convenience functions for constructing polygons and lines
from
> >> > points without having to construct intermediate objects
> >> >
> >> > Other things that need to be done at some point, but not
> >> necessarily
> >> > for 2.3:
> >> >
> >> > * refactor the code (what, already?) so that the Vector
> >> architecture
> >> > can support multiple rendering types (Canvas, SVG, VML,
possibly
> >> > others in the future) by introducing Layer.Vector subclasses
and a
> >> > new Rendering class that knows how to render into the
sub-classed
> >> > layer types
> >> >
> >> > * refactor styling support to make it less specific to
Canvas
> >> > rendering stuff
> >> >
> >> > * add some Controls for digitizing and possibly editing
> >> >
> >> > Cheers
> >> >
> >> > Paul
> >> >
> >> > On 12-Oct-06, at 7:55 PM, Christopher Schmidt wrote:
> >> >
> >> > > On Thu, Oct 12, 2006 at 05:02:00PM -0400, Paul Spencer
wrote:
> >> > >> Schuyler, et al
> >> > >>
> >> > >> attached is a first cut at the vector stuff. It
extracts
> >> over an
> >> > >> existing openlayers folder and contains only the
new files
> >> I've added
> >> > >> plus a change to OpenLayers.js to load the extra
files by
> >> default
> >> > >> (except for excanvas for some reason ;)).
> >> > >>
> >> > >> There is a vector.html in the examples folder.
> >> > >
> >> > > This code, with some improvements from Schuyler and I,
is now
> >> in place
> >> > > in a sandbox in the OpenLayers SVN. You can check out
with:
> >> > >
> >> > > svn co http://svn.openlayers.org/sandbox/sderle/vector/
> >> > >
> >> > > You can try it out at:
> >> > >
> >> > >
http://openlayers.org/~crschmidt/vector/examples/vector.html
> >> > >
> >> > > Click once to start drawing a line -- click again to
end it.
> >> > >
> >> > > FF only at the moment.
> >> > >
> >> > > Cool stuff, Paul, thanks for getting the ball rolling
on this.
> >> > > --
> >> > > Christopher Schmidt
> >> > > Web Developer
> >> >
> >> >
+-----------------------------------------------------------------+
> >> > |Paul Spencer
pspencer at dmsolutions.ca |
> >> >
+-----------------------------------------------------------------+
> >> > |Chief Technology Officer
|
> >> > |DM Solutions Group Inc
http://www.dmsolutions.ca/ |
> >> >
+-----------------------------------------------------------------+
> >> >
> >> >
> >> >
> >> >
> >> >
> >> >
> >> >
> >> > _______________________________________________
> >> > Dev mailing list
> >> > Dev at openlayers.org
> >> > http://openlayers.org/mailman/listinfo/dev
> >> >
> >> >
> >> >
> >> >
> >>
> >> <wkt.html>
> >> <WKT.js>
> > _______________________________________________
> > Dev mailing list
> > Dev at openlayers.org
> > http://openlayers.org/mailman/listinfo/dev
>
> +-----------------------------------------------------------------+
> |Paul Spencer pspencer at dmsolutions.ca |
> +-----------------------------------------------------------------+
> |Chief Technology Officer |
> |DM Solutions Group Inc http://www.dmsolutions.ca/ |
> +-----------------------------------------------------------------+
>
>
>
>
> _______________________________________________
> Dev mailing list
> Dev at openlayers.org
> http://openlayers.org/mailman/listinfo/dev
>
>
More information about the Dev
mailing list