Under the Windows and Windows NT environments, you may set the configuration variable 3D-LINES to "1" to cause the runtime to display lines and boxes with 3-D shading. This makes the lines appear to be inscribed into the surface of the screen. Only black lines on a non-black background are shown with shading. Other lines are displayed normally.
The set of colors available to ACUCOBOL-GT significantly impacts how effective the shading will be. Normally, the shading is most effective when the background is low-intensity white. The other low-intensity colors are next best.
The shading is only marginally effective with a high-intensity background. For this reason, the 3D-LINES setting is not used when a high-intensity background is drawn. Note that, by default, ACUCOBOL-GT shows background colors in high-intensity, so you will need to use at least one other configuration variable to arrange for a low-intensity background color. For example, the BACKGROUND-INTENSITY variable described in Appendix H, Book 4, "Appendices" could be set to "1" to force a low-intensity background.
Under Windows and Windows NT, you may freely change the way lines are displayed in COBOL by using the SET ENVIRONMENT verb to set 3D-LINES, prior to displaying a line or a box.
The runtime remembers which lines are drawn with 3-D, so you do not need to keep track of this yourself. Note, however, that if you attach a 3-D line to a non-3-D line, the intersection will use the 3D-LINES setting currently in effect.