A node-link structure is displayed within a display area, having a narrow rectangular
shape with an edge along one side acting as a horizon of a hyperbolic space half-plane.
Lower level node features that share a parent node feature have centers of area
positioned on the display in order along a line parallel with the horizon, with
sufficiently similar spacings along an axis perpendicular to the horizon from the
region around a parent node feature, and with sufficiently similar spacings in
a dimension parallel to the horizon from adjacent node features along the line,
that the lower level node features sharing the parent node feature are perceptible
as a group of related node features. The half-plane model with compression is used
for layout of the node-link data, and the hyperbolic layout data is mapped to a
Euclidean space for display.
