On Feb 1, 2008 1:33 PM, Martin Desruisseaux <[EMAIL PROTECTED]> wrote: > Simone Giannecchini a écrit : > > Yeah but you are referring to a specific convetion. What if I give a > > netcdf file that does nto follow that specific convention? > > As far as I know there are at least ) conventions. And what if I give > > you a file that does not follow any convention at all? > > Then we fall in the same case than PNG. The rule is to use metadata when they > are available (either from the file or user-supplied), and to not make any > assumption if they are not (again if the coverage module tries to switch to > geophysics view when there is no metadata, it would be a bug). > > > > > Moreover if you look at how OGC has standardized this, applying colors > > shiould be guided by the usage of SLD not by the implicit applications > > of colormaps. > > Implicit applications of colormaps should happen only if: > > - The original data are floating point values. > - No colormap map were found in the file or provided by user. > > Only in such case a default colormap is created. Its only purpose is to allow > user to see his data straight after GridCoverage2D creation time. If he never > display his data before SLD, the RenderedOp image is never rendered so the > cost > should be small. > > > > I agree that there might be perfomance issue with this approach, but I > > don't think that OGC guyes where completely wrong :-) > > This is not a performance issue. A default colormap is used at GridCoverage2D > creation time if none was specified only as a way to see the data immediately > (and only if the user wants to see them), and anyone is free to modify it > after > creation with "Recolor" or whatever operation. >
I meant to say there might a performance penalty in trying to apply colormaps at a later stage using SLD with respect to creating them at an early stage where more information about the actual data are available like you are dsuggesting. Simne. > Martin > > -- ------------------------------------------------------- Eng. Simone Giannecchini President /CEO GeoSolutions S.A.S. Via Carignoni 51 55041 Camaiore (LU) Italy phone: +39 0584983027 fax: +39 0584983027 mob: +39 333 8128928 http://www.geo-solutions.it ------------------------------------------------------- ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Geotools-devel mailing list Geotools-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/geotools-devel
