This is a first draft. The way geometry changes are handled for
now is a bit clumsy. Both updating the feature cache RTree and
making the layer aware of feature and geometry changes could be
handled in a smarter way if these changes would be made through
the layer instead of directly on the geometry or feature.
The tests revealed that polygons can be drawn with counter-clockwise exterior ring order. In the polygon constructor, we enforce clockwise winding for exterior rings. So after drawing, we pass polygon coordinates back to the constructor before adding feature to the target layer.
This allows us to cast single-part geometries to multi-part types before adding features to the target layer. This doesn't yet allow for drawing multi-part geometries with multiple parts. That can be handled separately.
Our geometries are mutable, so they can be modified without
creating garbage by changing coordinates in place and calling
setGeometry afterwards. But this also means that we need to
create a deep clone of the coordinates.
This adds a new ol.source.MapGuide class that is initialized with an options object that can contain the following values:
- projection: The projection of the Map Definition in EPSG format
- url: The mapagent URL
- useOverlay: Determines whether the GETMAPIMAGE (false) or GETDYNAMICMAPOVERLAYIMAGE (true) will be used for requesting the map image. When using GETMAPIMAGE, you must include a valid MAPDEFINITION parameter in the 'params' option property. When using GETDYNAMICMAPOVERLAYIMAGE, you must include a valid SESSION and MAPNAME parameters in the 'params' option property.
- metersPerUnit: A required value used for calculating the map scale needed by the image request. This value can be calculated using the MapGuide Web API or obtained through the new CREATERUNTIMEMAP operation in MapGuide Open Source 2.6
- params: A set of key-value pairs to append to the mapagent request
- extent: The bounds of the layer
An example is included to demonstrate this new layer source. Like ol2, this example uses the MapGuide Server on data.mapguide.com
