A Graph Library Extension of Svg

This paper describes an extension of SVG that supports the drawing of graphs in terms of nodes and edges in between nodes. The graph drawing primitives support a variety of different node shapes, edge connection points, and edges. Both nodes and edges can be labeled. Two or more nodes can be aggregated as a single node, and an entire graph can be embedded into a single node. In addition, a number of different graph animations are described. The starting point of the SVG extension is a library that provides an exact of mirror of SVG 1.1 in the functional programming language Scheme. Each element of SVG 1.1 is represented as a specific function in Scheme. The graph drawing primitives are implemented as functional abstractions on top of the SVG 1.1 mirror functions. It is argued that the SVG extension approach, as exemplified by the graph drawing facilities, is useful whenever an author wish to control the complexity of a non-trivial SVG document.