Messages from Usenet group comp.lang.idl-pvwave, compiled by Paulo Penteado
Hi, there. I've recently made the switch (as a user, not as sysadmin!) from a Sun Ultra running Solaris to a PC running Red Hat 6.2. No big deal, perhaps, but I'm having to come to terms with using a decent graphics card with 24-bit colour when using IDL (and the various astronomy add-ons like CDS and SolarSoft). My problem is this: I used to use a very nifty display routine by Paul Ricchiazzi called TVIM.PRO, which always did the job brilliantly for me. It still plots fine on a postscript device, but when you use it to display an image on your 24-bit colour XWindow, the colour table doesn't scale nicely. If you're using colour table 0 (greyscale), for example, to view a 2-D image, then it doesn't scale from black (minimum data value) to white (maximum data value) as it would under an 8-bit display. I know that the colour system under 24-bit isn't as straightforward as under 8-bit, for which (I read) IDL is optimised. Because so many of my routines (and some of my colleagues') depend on TVIM and all its nice keywords, does anyone know of a way to make TVIM display things properly on a 24-bit XWindow? The only kludge I've been able to get to work so far has been to get our sysadmin to cripple the machine's display to 8-bit colour, which seems like a rather ham-fisted way of doing things. Any help would be _greatly_ appreciated, thanks for taking the time to read this, Dave Williams, Belfast. --