TOPIC:

When running RiverTools 2.4 on a UNIX system, sometimes the colors will appear incorrect, or will flash as you move the cursor from one window to another. Often the color problem is first noticed when a shaded relief display is generated and appears to use a bad color table.

DISCUSSION:

If your system uses 24-bit color, this problem is usually caused because Direct Color is used instead of True Color. You can force IDL to always use True Color (thereby eliminating these color problems) by setting up your .Xdefaults file to contain the following two lines. If you do not have a .Xdefaults file in your home directory you can create one using a text editor, and enter these two lines into it:

idl.gr_visual: TrueColor
idl.gr_depth: 24

To get these changes to take effect without exiting your UNIX session, type this at the UNIX prompt:

xrdb -merge .Xdefaults

If your system does not have 24-bit color, the TrueColor visual class will not be available. In this case, any color problems are probably due to RiverTools using a shared color map. When an application starts, the window manager allocates colors in the shared color map for the borders of windows, the foreground and background colors, and other needed resources. If the number of colors the application requires is available in the shared color map the window manager will assign the application's requested colors to entries in the shared color map. But if the application requests more colors than are available in the shared color map the window manager will create a private color map for that application. Moving the cursor from that application to another application will cause the system to switch from the private color map associated with the first application, to the private color map associated with the second application. This type of color flashing is normal for systems with only 8-bit color.

If you have any additional questions or comments, please contact Rivix Technical Support for assistance.