Hello Luis, I saw the video of the webinar of your colleague João P Leitão in April about the hex version of the CADDIES model and I was asking myself "is there any GIS software supporting hexagonal rasters?" So I'm quite excited about the prospect of having support in GRASS ;) However, I'm not sure if I can be of much help about the implementation.
Regards, Laurent Courty 2017-07-23 10:50 GMT-05:00 Luís Moreira de Sousa <[email protected]>: > Dear friends, > > I presented hex-utils at the GISTAM conference in April, here is the video: > https://www.youtube.com/watch?v=uLO4HDCVBp0 > > This was before the QGis plug-in was completed, but for the rest it is > pretty much the same story. > > Before the FOSS4G-E, in my mind the next phase of the project would be to > code the abstraction functionalities in C++ (or C), to make it fully > portable and easier to use with other languages, particularly Java. After > that would then come a map algebra and spatial analysis. > > But as Luca said during the Q/A, it is probably better to start outright > within GRASS. This will require the abstraction of the raster concept, > together with operations like neighbourhood, number of neighbours, distance > to neighbours, etc. With that done most of the raster modules would function > the same way for squared and hexagonal rasters. Still, this would require a > complete revision of all the raster modules. > > For a programmer, the main difference between hexagonal and squared rasters > is the cell addressing system: with hexagons the axis are not orthogonal. > However, it is possible to store an hexagonal raster in a bi-dimensional > array like you would store a squared raster. I wrote an article last year > with full details on the HexASCII file format and how to deal with hexagonal > cell adressing, but it is still under review. I can not send it to the list, > please send me a personal message if you wish to read it. > > It would be great if we can take this forward. I imagine it is a load of > work, but it will make GRASS an even more awesome system ;) > > All the best. > > -- > Luís Moreira de Sousa > Im Grund 6 > CH-8600 Dübendorf > Switzerland > > Phone: +41 (0)79 812 62 65 > Email: [email protected] > URL: https://sites.google.com/site/luismoreiradesousa > > > > _______________________________________________ > grass-dev mailing list > [email protected] > https://lists.osgeo.org/mailman/listinfo/grass-dev _______________________________________________ grass-dev mailing list [email protected] https://lists.osgeo.org/mailman/listinfo/grass-dev
