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→The H-Tree: move here
The Genealogy program [http://www.ics.uci.edu/~eppstein/gene/UserGuide.html#txgrid Gene] first called this type of chart the '''Ancestor Grid'''. eg: ''A different type of ancestor tree drawing, the "Ancestor Grid", connects generations alternately left-right and up-down, so that ancestors are spread in a grid around their common descendant. The horizontal or vertical style determines which direction is used first. The tree structure of these drawings is less clear than in the "Ancestors" tree but the grid can sometimes fit more names in the given space. Unlike the other tree drawings, when the ancestor grid runs out of room to add more generations it simply cuts the tree off, without adding any ellipses. Below we show a horizontal ancestor grid.'' Gene 4.3 User Guide:4.3. Ancestor trees and grids, Copyright 1995-2000 David and Diana Eppstein. At least as far back as [https://web.archive.org/web/19970502091401/http://www.ics.uci.edu/~eppstein/gene/UserGuide.html#ancestor%20trees][https://www.ics.uci.edu/~eppstein/gene/TechNotes.html#history Added to Gene v4.0 in June 1994, ''Improved tree drawings including more font sizes, more styles, new ancestor grid layout, menu to switch layout type within the tree dialog, and ability to save PICT files.'']
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== Implement the charting method used in Gene program ===
[[Existing_reports#Gene Gene]]: The example is a descendent chart, but other charts are also part of Gene, see [http://www.ics.uci.edu/~eppstein/gene/UserGuide.html#trees here]. This is the most space efficient method I have seen - it has the clearest charts with the least amount of white space. Implementing it may rely on getting information from [http://www.ics.uci.edu/~eppstein/ David Eppstein], though there is quite a lot on his website about his research on graph drawing techniques. I have tried to contact him to see whether he would share the code of his algorithms, but he has never replied - perhaps someone who has academic contacts could try to connect with him again.
== The Gene-Tree ==
