Currently OpenLayers only supports a limited subset of the Styled Layer Descriptor (SLD) specification. This work item can be used to expand support on various dimensions, including multiple symbolizer support, more labeling and rendering options, and even support for the Symbology Encoding (SE) 1.1 specification. Many of these improvements will involve upgrades to the core OpenLayers style objects. The result of these will be richer live editing of styles, and improving the capabilities of OpenLayers to edit SLDs and send them to a server to be rendered.
Multiple Symbolizer support will give OpenLayers the rich rendering rules that people expect from good looking maps, being able to do things like put black outlines on a white road, or style a polygon's center point in addition to the outline and fill. To actually create and edit multiple symbolizers the GeoExt Symbolizer Improvements item will be required.
There are also a variety of edges of the SLD specification, for richer labels and rendering rules, which would be nice to complete. The other piece needed for the constrained web environment that OpenLayers runs in is support for POSTing SLDs to be rendered. The WMS specification supports a couple mechanisms for a client to have the server render a defined SLD. OpenLayers right now uses the inline method, passing the xml in with the GET request stream. With rich (long) SLD files, however, it will hit browser request limits. The better way to do this is to POST the SLD to an alternate location, and then pass that location in to the server. This is required to make OpenLayers the basis for a standalone SLD editor that can handle any file.
Funding
This roadmap item is currently unfunded.
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Other Roadmap Items
Full Support of Styled Layer Descriptor (SLD) specification
OpenLayers has basic support of the SLD specification of the OGC, but there are a number of more advanced options that it does not support. Among those are multiple symbolizers per rule and advanced labeling and rendering options. Another improvement needed for the web environment is to to support POST requests for WMS/Image layers to overcome the url length limitation (e.g. when using client defined SLD for rendering).
CQL is a terse language for writing data filters. This item will allow users to flip between a GUI view of the filter and a text view of the filter in CQL, and edit either one.
Polygon collections are very often generated as sets of shapes that share boundaries. Rather than digitizing new polygons and using snapping to create a duplicate bounding, a “build polygon” tool allows users to add new polygons on to the sides of existing polygons.