Used to mark an implementation of RenderImpl.class; responsible for rendering a layer.
A renderer has the following responsibilities:
A renderer must draw to the image provided by it RenderContext
A renderer reprojects victim data if required
A renderer applies styles if necessary
A renderer is responsible for registering with its layers to obtain notifications whent the
layers' styles change
If a renderer does not extends the RendererImpl class the renderer must notify its
adapters(listeners) when its rendering state changes.
If a renderer does extend the RendererImpl class it must call the setState() method
when its render state changes or it wishes to notify its listeners that it needs to be redrawn.
The state that the renderer can use are the following:
RENDERING - should be called when the renderer has data that it wishes to display on the
screen.