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Re: [zzdev] Levelraster

Tuomas Lukka wrote:
> Umm, Benjamin, could you explain how the structure of the levelraster
> works: I tried it but couldn't make sense of it. Preferably in he initial
> comment: how are the two dimensions interpreted.

Let me postpone the detailed explanation until I've finished the raster
-- I mean, things may change on the way. Here's a short version to
hopefully clue you in.

This is about visualizing many-to-many relationships. To create such
beasts in zz structure, you need to put in link cells to connect stuff,
there's no way around this.

The level raster uses three dimensions: link, target and tunnel. The
cells one node LINKS TO can be found by going poswards on the link dim
(each cell poswards counts) and then going to the tailcell on target
dim. The other way around, the cells that a node IS LINKED FROM can be
found by going negwards on target dim (all cells negwards count) and
then going to headcell on linkdim.

The cells in between are the links, and are rendered small in the middle
of the collecting line in link raster.

Tunneldim is a shortcut: the cell posward on tunnel is thought of as
linked to from this cell. The cell negwards has a link to this. These
links don't have a link cell and thus, none is drawn.

Trying this out on other zz structures mostly causes a lot of confusion;
create a special structure for it. (On the other hand, for such special
structures it can be very useful -- for example, to visualize the links
between HTML pages, or to visualize the flow of a program.)

Hope this helps,
- Benja