The BW2 is a simple 1-bit frame buffer supporting monochrome monitors. The device handler for this device exports the 1-bit StaticGray visual only. Therefore, this is the built-in default visual. A variety of BW2 frame buffers are available for different buses and screen resolutions, including third-party offerings.
The CG3 is a simple 8-bit indexed color, dumb frame buffer for SBus systems. The device handler for this device exports several 8-bit visuals (listed in the following sections). The built-in default visual is 8-bit PseudoColor.
The GX is an 8-bit indexed color graphics accelerator, specializing in 2D and 3D wireframe, flat-shaded polygon, and general window system acceleration. Window system acceleration is automatic; you can access other acceleration features through Solaris graphics APIs. Several 8-bit visuals are supported, and the built-in default visual is 8-bit PseudoColor. The GX is available for SBus and P4 bus.
The GXplus device is similar to the GX with additional memory that can be used for double buffering and expanded screen resolution on SBus systems. The Solaris X server uses the GXplus to automatically accelerate X11 pixmaps by using offscreen storage whenever possible.
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.