[OpenLayers-Dev] [Dev] Re: Vectors in OpenLayers?
Paul Spencer
pspencer at dmsolutions.ca
Thu Oct 19 08:11:34 EDT 2006
For you maybe ;) GML would be another good output choice I guess
Paul
On 19-Oct-06, at 3:44 AM, Bart van den Eijnden (OSGIS) wrote:
> 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/ |
>> +-----------------------------------------------------------------+
>>
>>
>>
>>
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>>
>
>
>
+-----------------------------------------------------------------+
|Paul Spencer pspencer at dmsolutions.ca |
+-----------------------------------------------------------------+
|Chief Technology Officer |
|DM Solutions Group Inc http://www.dmsolutions.ca/ |
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