On 11 October 2011 03:44, kaffeepause73
First of all - thanks a lot for this package, graphviz is an awesome tool and having this interface library is really convenient. There a three point where I could use some help:
2. I know how to rotate the whole diagram (with landscape or rotate 90), but not how to keep all the text in unrotated position -- is there a command to do this ?
I don't think this is possible: the rotation seems to be a post-processing feature done by GraphViz. If you just want the graph laid out Left-to-Right rather than Top-to-Bottom, try setting the RankDir attribute: http://hackage.haskell.org/packages/archive/graphviz/2999.12.0.3/doc/html/Da... (though I've just noticed that the Ordering attribute should take in a specific type rather than just Text... *goes off to fix*)
3. When I create a symmetric tree with two directions on the two sides. The tree gets completely messed up when I enter the right directions. (left graph ok but wrong edge dirs, right graph with correct dirs but gemetry scambled). - It has todo with ranking order which is based on the direction of the edges. I can fake it with reversing the arrows in the diagram, but my original graph data is coming directed ...
This means you need to tweak and play around with the settings more. My approach (and I'm the maintainer of the graphviz library!) for stuff like this is: * Get some sample Dot code (either write it by hand or use graphviz to generate it from your data). * Look through all the available attributes for ones that might deal with layout of nodes, edges, etc. at: http://www.graphviz.org/doc/info/attrs.html * Try setting them into your Dot code, then use the appropriate Graphviz command (dot, neato, circo, etc. depending on which layout you want); consider something like "dot -Txlib test.dot" to get a preview window up, or "dot -Tpng test.dot > test.png" to get a png image. * Once you've found attributes that seem to do what you want, use the graphviz versions of them in your Haskell code. Note also that because Graphviz uses automatic layout algorithms, you can't always get it to output in the way that would make sense if you drew it by hand. I've been told that things like phantom nodes (invisible nodes that you insert with extra edges to force spaces, alignment, etc.) can help, but I've never looked into using them enough to work out approaches of how/when to do so. -- Ivan Lazar Miljenovic Ivan.Miljenovic@gmail.com IvanMiljenovic.wordpress.com