WPALETTE-SET-COLOR (op-code 4)

This function complements WPALETTE-GET-COLOR; it lets you assign a new color to a particular color number. At entry, WPAL-COLOR-ID should contain the color number you want to change. WPAL-RED, WPAL-GREEN, and WPAL-BLUE should contain the RGB value of the new color (see WPALETTE-GET-COLOR for a description of RGB values).

For example, if you want to make color number 2 represent a dark blue-green, you could use the following values:

WPAL-COLOR-ID	2
WPAL-RED	0
WPAL-GREEN	64
WPAL-BLUE	64

Note: Changing the palette will change the colors currently shown on the screen as well as all future displays. In the previous example, if you had displayed any data (or background) using color number 2, that data would now change to dark blue-green.

The color palette is the lowest level of color handling in the ACUCOBOL-GT system. It defines the basic set of colors used. Although you are free to change the palette as you see fit, ACUCOBOL-GT makes certain assumptions that you should be aware of. First of all, ACUCOBOL-GT assumes that color 1 is always black, and color 16 is always bright white. Likewise, colors 8 and 9 are assumed to be shades of gray. These assumptions affect the rendering of window shadows and 3-D lines. Additionally, the first 8 colors are assumed to be low-intensity, and the second 8 are high-intensity.

ACUCOBOL-GT computes the high- or low-intensity version of a color by adding or subtracting 8 from its color number. This assumption also affects the rendering of 3-D lines if you use them on a colored background. Although you are not required to maintain any of these assumptions, be aware of them so that you can anticipate the total effects of your changes.