In addition to the generic capabilities covered in #10, defining a conceptual model, logical model and encodings for styling vector features, defining types of expressions for use within selectors and symbolizer parameter values, as well as symbolizer properties applicable specifically to vector features.
Expressions extension
referencing feature attributes
referencing a record (including e.g. its ID, or geometry)
referencing a geometry's dimensionality (e.g. 0D, 1D, 2D or 3D geometry)
Symbolizer extension
fill for polygons (solid, gradient, hatch, stipple, pattern; color/opacity)
strokes for lines and polygons (solid, dash pattern, graphical pattern; color/opacity; width; join & cap style; potentially explicitly specifying a casing and/or centerline)
markers (a single set of graphical elements to always be rendered at a precise location of the geometry)
basic labels (a single set of graphical elements to be placed by label placement algorithms if room allows e.g. based on priority, and rendered, with a minimum set of properties and minimum guidance on how an engine would place and render these). A separate extension would add more advanced labeling capabilities / placement options.
a definition of graphical elements types which may be included as part of markers and labels, as well as for pattern fills & strokes.
Images (hotspot; tints)
Text (text string, alignment, font (face, bold, italic, size, color, opacity, outline))
Shapes (dot, rectangle, circle, ellipse, arc, path -- open or closed polygon), themselves with fill and strokes settings
In addition to the generic capabilities covered in #10, defining a conceptual model, logical model and encodings for styling vector features, defining types of expressions for use within selectors and symbolizer parameter values, as well as symbolizer properties applicable specifically to vector features.
Expressions extension
Symbolizer extension