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>From: "Matthew J. Rosier" <address@hidden> >Organization: UCAR/Unidata >Keywords: 200306120313.h5C3DJLd003079 >I'm having a problem changing the default (map background) color in any >GEMPAK application. I've tried using Ncolor, but for some reason, when I >click on a color, nothing happens. > >I've tried putting white as the first color in the coltbl.xwp file, still >nothing happens. >I've even tried changing the RGB values for black in coltbl.xwp. No luck. > >Perhaps I am overlooking something obvious. Any ideas? > >Much thanks, > >Matt > > Matt, The Ncolor program changes the color indexes, which can only be done with 8 bit color (indexed color) displays. For true color direct color access (16/24 bit depth), Ncolor will have no effect. Changing the first color in coltbl.xwp will set the background color for an application when the application defines its own color table. This is particularly useful when creating GIF files using a virtual X server (where ntl is not running). When running NTL, a shared color table is established for all programs. The background color is set in the $NAWIPS/resource/Ntop file. See the comments in the resource file. To set to white, uncomment the last line: Ntop*appbgName: white The other colors assigned to the shared color table in ntl are defined in: $NAWIPS/tables/nawips.clr Steve Chiswell