TC (CG8)

The TC device possesses two separate memory buffers, or plane groups: 1-bit monochrome and 24-bit color. Windows may be created in both plane groups; therefore, it is an MPG device. All 1-bit and 24-bit visuals are supported.

Some (older) X11 client applications assume that color frame buffers use an 8-bit built-in default visual and do not run in color on the TC. To avoid this, the built-in default visual is 1-bit StaticGray.

The plane groups of the TC do not conflict with each other; they are completely separate memory buffers. OpenWindows takes advantage of this to increase system performance by not damaging 1-bit windows when they are occluded by 24-bit windows, and vice versa. This behavior is called minimized exposure. Use the -nominexp option of openwin(1) to disable this behavior. If this option is used, 1-bit windows will damage 24-bit windows and 24-bit windows may damage 1-bit windows.

The Solaris X server also provides minimized exposure for other MPG devices, when applicable. Use the -nominexp option of openwin with these devices.

The X protocol states that cursor components can be arbitrarily transformed. To enhance general system performance, the OpenWindows server always renders the cursor in the 1-bit plane group of the TC.