enhance Format.GML to parse gml:boundedBy

[bartvde]

This is e.g. handy when you want to zoom to the full featureCollection.

[bartvde]

A problem though is that the read function currently returns an array of features, so there is not really "space" to put an extra return value. If it would return an object with an array of features, there wouldn't be an issue. But changing this will also influence Layer.GML and other code that currently uses Format.GML, so I don't know if this is acceptable.

[crschmidt]

The way we've addressed this type of requirement is to require additional options to be passed to read which say something like 'return some different type of object': so if 'read' gets a 'returnBbox: true' option, then read can return something other than a list of features.

[bartvde]

Thanks Chris, I'll take that into account when creating the patch.

[crschmidt]

Tim: I think you had mentioned at one point you were working on an improved GML parser. (One that didn't use so much slow getElementsByTagNameNS.) Is that the case?

[bartvde]

On the mailing list Tim pointed to this:

http://trac.openlayers.org/browser/sandbox/topp/almanac/lib/OpenLayers/Format/GML/Base.js

I'll try and update the patch to avoid getElementsByTagNameNS for the added functionality.

[bartvde]

updates patch which does not fail when <gml:null>missing</gml:null> is in the GML

[tschaub]

I'm going to bump this as well. If someone else can review before the end of the week, please pull this back to 2.7.

[bartvde]

patch rewritten against OpenLayers.Format.GML.v2

[bartvde]

Okay, I've finally rewritten my patch against the OpenLayers.Format.GML.v2 parser of OL 2.7. Please review.

Example useage:

    ..
    var g =  new OpenLayers.Format.GML.v2(options);
    var features = g.read(response.responseXML || response.responseText);
    // boundedBy will contain the boundary of the whole feature collection
    // easy for zooming to the selection / collection
    console.log(g.boundedBy);
    ..

[tschaub]

(In [8809]) Adding a test to confirm that reading of boundedBy works for GML 2 as well (see #1918, #1613)

[tschaub]

Thanks for the patch Bart. I added support for reading boundedBy in GML 2 and 3 in r8808. I'll mark this as a duplicate of #1819. Reopen if there are issues.