Messages from Usenet group comp.lang.idl-pvwave, compiled by Paulo Penteado
Re: getting procedures to use proper color index via LOADCT, x
dmarshall@ivory.trentu.ca wrote: > But then my plots only ever show up in various shades of red. device, decomposed=0 From the IDL online help: Set this keyword to 0 to cause the least-significant 8 bits of the color index value to be interpreted as a PseudoColor index. This setting allows users with DirectColor and TrueColor displays to use IDL programs written for standard, PseudoColor displays without modification. Set this keyword to 1 to cause color indices to be interpreted as 3, 8-bit color indices where the least-significant 8 bits contain the red value, the next 8 bits contain the green value, and the most-significant 8 bits contain the blue value. This is the way IDL has always interpreted pixels when using visual classes with decomposed color. Best regards Kevin -- Kevin Ivory Tel: +49 5556 979 434 Max-Planck-Institut fuer Aeronomie Fax: +49 5556 979 240 Max-Planck-Str. 2 mailto:Kevin.Ivory@linmpi.mpg.de D-37191 Katlenburg-Lindau, GERMANY http://www.gwdg.de/~kivory2/
In article <ELK5uC.1G0.A.ebony@news.trentu.ca>, dmarshall@ivory.trentu.ca writes: > A lurker de-lurks: > > I am running Student Version IDL 5.0 on Windows 95 > > I cannot get procedures like SURFACE etc to access the loaded color table. > > LOADCT, 5 > > Gives me no problem, no error messages and it confirms loading the table. > > But then my plots only ever show up in various shades of red. > I confirm this by running CINDEX. It sounds like your display is set to True Color. Do HELP, /DEVICE to check. If it is then doing SURFACE, COLOR='50'x will produce a red plot. However doing SURFACE, COLOR='505050'x will draw using the correct color in your lookup table. True color in IDL is pretty tricky, and not very will documented IMHO. David Fanning's Web page has some very useful tips. You can also simply change your display to 256 colors, but then you have the limitations of a limited color map. ____________________________________________________________ Mark Rivers (773) 702-2279 (office) CARS (773) 702-9951 (secretary) Univ. of Chicago (773) 702-5454 (FAX) 5640 S. Ellis Ave. (708) 922-0499 (home) Chicago, IL 60637 rivers@cars.uchicago.edu (e-mail) or: Argonne National Laboratory (630) 252-0422 (office) Building 434A (630) 252-0405 (lab) 9700 South Cass Avenue (630) 252-1713 (beamline) Argonne, IL 60439 (630) 252-0443 (FAX)
In article <349E1DA1.DDBA7E22@linmpi.mpg.de> Kevin Ivory <Kevin.Ivory@linmpi.mpg.de> writes: > From: Kevin Ivory <Kevin.Ivory@linmpi.mpg.de> > Subject: Re: getting procedures to use proper color index via LOADCT, x > Date: Mon, 22 Dec 1997 08:58:25 +0100 > dmarshall@ivory.trentu.ca wrote: >> But then my plots only ever show up in various shades of red. > device, decomposed=0 > From the IDL online help: > Set this keyword to 0 to cause the least-significant 8 bits of the color index value to be interpreted as a PseudoColor index. This setting allows users with DirectColor and TrueColor displays to use IDL programs written for standard, PseudoColor display > without modification. > Set this keyword to 1 to cause color indices to be interpreted as 3, 8-bit color indices where the least-significant 8 bits contain the red value, the next 8 bits contain the green value, and the most-significant 8 bits contain the blue value. This is th > way IDL has always interpreted pixels when using visual classes with decomposed color. That would be nice. It doesn't work on SGI workstations, so I would guess it might not work on other X-windows systems--haven't had a chance to try. Of course, I am using an old version of IDL, and have never played with the .xdefaults file. But Fanning claims it works on PCs. ------------------------------------------------------------ - Mitchell R Grunes, grunes@imsy1.nrl.navy.mil. Opinions are mine alone.