Hi there. I´ve downloaded the latest gvSIG version, 1.12 final. I´ve installed it (activated GRASS and SAGA in the Sextante options) and used right away because I have an academic work which consists of developing a spacial analysis exercice using raster operations, first using ArcGIS and then I must replicate it using an opensource, in my case gvSIG. In the process, here are a few problems I´ve came up to:
1 - Sextante doesn´t allow to create a DEM-TIN like I did using 3d Analyst of Arcmap; SAGA has a function called "Shape to TIN" but it doesn´t generates an output ; 2 - I need to create a DEM in order to generate slope and aspect charts for my area of study. Since there isn´t an option to define a mask (like there is in Arcmap), I did a clip using the shape with altimetric information as input and the area of study as clipping layer. The result has the altimetric information for my area of study. Then I need to rasterize this result layer. So I went to Sextante and used "Rasterize vector layer" in order to convert it to raster format, having defined an appropriate cell size and the extent as my area of study ( in the hope that the result would have the form of my area of study). Then I did a void filling ( I´ve read this somewhere) to generate a proper DEM. But unfortunately the result is a rectangular DEM instead of being limited to my area of study (which by the way is the portuguese equivalent to an ayuntamiento) Why? 3 - There is an option in Sextante called "Rasterize vector layer (for mask)" but it doesn´t seem to do what i want. 4 - The GRASS function v.to.rast is to confusing and doesn´t work properly. It gives an error :Failed to import data into GRASS mapset; 5 - The reclassify function of sextante is a bit confusing as well. It requires a min value, a max value and a new value. For example, if i need to reclassify a slope chart, e.g, 5 classes (0-10%, 10-20%, 20-30%, 30-40% and >40%). I have put the min and max for the each class. Why do I need to write new values? Shouldn´t the program assume that? I´ve tried to write 1, 2, 3, 4 ,5 (to match the classes) but the output has 0 value in some pixels but there is no class 0. Why? 6 - Why haven´t the programmers of the latest version improved the symbology options and visualization in rasters. It´s a pain having to work in black, grey and white and not be able to see the classes of a certain raster with different colors (with this being shown in the view) Thank you very much for the attention. I would be really thankful for answers to my questions. It´s kind of an emergency. Regards, André Pais. -- View this message in context: http://osgeo-org.1560.n6.nabble.com/raster-limitations-tp5004684.html Sent from the gvSIG users mailing list archive at Nabble.com. _______________________________________________ Gvsig_internacional mailing list Gvsig_internacional@listserv.gva.es To see the archives, edit your preferences or unsubscribe from this mailing list, please access this url: http://listserv.gva.es/cgi-bin/mailman/listinfo/gvsig_internacional