Framework for generalized mappings from graph attributes to visual attributes. Graph attributes are either in the form of the actual nodes and edges of the graph, or in the form of values stored in one of {@link cytoscape.CytoscapeWindow CytoscapeWindow}'s two {@link cytoscape.CyAttributes CyAttributes} instances, {@link cytoscape.CytoscapeWindow#edgeAttributes edgeAttributes} and {@link cytoscape.CytoscapeWindow#nodeAttributes nodeAttributes}. Visual attributes include node color, size, shape, label, edge color, style, label, etc.