Hello, I've been working on a new plugin for some weeks, aiming to let people do flow mapping within QGIS. Eventhough the plugin is yet not releaseable due to many bugs and unfinished features, I just wanted to announce it in case somebody would be interrested in it or would be working on something similar.
Features (done and scheduled) : _Creating simple lines from an origin/destination table + a point layer, or from o/d + polygon layer. (this feature should be quite easy to do, but yet, I didn't work on it, and it could be implemented in another plugin that would only be used for those lines creations). _ Creating and exporting Bezier curves within QGIS, through a global or feature by feature manual editing. The aim of this feature is to let user design Bezier curves within QGIS, without having to use a third party tool like Inkscape or Adobe Illustrator. Considering geometries do not handle arcs neither curves, the shapefiles will be segmented, but the SVG export is a native Bezier curve. I can't use the map composer for it, as it don't support Bezier path. This feature half works : I can create automatically Bezier control points, and edit them manually, and then, convert all of the lines to Bezier. I've been designing a maptool object for transparent manipulation, and work is still in progress in this domain. The exported SVG should also be "importable" and editable in QGIS, so that user can keep a track of their manipulations on a flow map. _ Applying some algorithms to flows : Currently, I implemented an algorithm named FDEB (Force-Directed Edge Bundling, see here : www.win.tue.nl/~dholten/papers/forcebundles_eurovis.pdf<http://www.win.tue.nl/%7Edholten/papers/forcebundles_eurovis.pdf> ) whose goal is to apply a bundling to lines, somehow similar to magnetic fields attraction, in order to spot patterns and axes in dense flow maps. Even if this is quite long to apply on medium/large shapefiles, it's working the way it should :) I'm considering the implementation of another algorithm for "spider" maps, that can be found and explained here :http://gis.stackexchange.com/questions/5204/curved-point-to-point-route-maps/5224#5224 A first, experimental, experimental version should be released within some weeks, and then, I'll ask for your feedbacks :) Until this, you can of course give me ideas/notices on what should be in the plugin, and you can consult the sources here, keeping in consideration that qFlowMapper is still under a lot of development : https://github.com/RCura/PluginFlux Thanks to the community for the help given so far, Robin.
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