We have the following "degrees of freedom" we wish indicate and allow modifcation of using the user interface.

• Visiable - rendered (or not)
• Selected - concept of the current Layer
• Editable - editable (or not)
• Glyph - legend glyph indicating Style - allowing assocation of layer with rendered features
• Rendering Order - usually expressed as order in the [Layer Vew]

It is interesting to look at the GIS Client Comparison to see how several applications track these changes.