Additional Color Configuration Variables

This section describes four additional configuration variables that can be used to determine how colors are displayed. Read this section only if you want to understand the exact effects of the various COLOR_MODEL settings or want to experiment with its component settings. For most sites, COLOR_MODEL and COLOR_TABLE will be adequate for color control.

The four additional configuration variables are:

For each character position on the screen, ACUCOBOL-GT assigns four values: the foreground color, the background color, the foreground intensity, and the background intensity. Your COBOL application may directly control three of these attributes with various ACCEPT and DISPLAY options. The attributes you control are the foreground and background colors, and the foreground intensity. You do not have direct control of the background intensity from the ACCEPT or DISPLAY verbs.

When the runtime system displays screen data, it performs a series of steps to transform the colors and intensities specified by your program to the actual colors and intensities shown. You can use a variety of configuration options to effect these transformations. By doing so, you can alter the appearance of your program without changing any of the program's code.

In order to explain the available configuration options, we will walk through the steps taken by the run-time system. At each point where an option can affect the results, that option is described.