Solaris supports the OpenGL visual expansion. With visual expansion, five visual groups: the 8-bit PseudoColor, 24-bit TrueColor (Linear and Non-Linear), 24-bit DirectColor, and 8-bit PseudoColor Overlay, are expanded from a single visual to multiple visual instances of the same visual type. Different instances of the same visual groups represent different GLX capabilities (e.g. single-buffer or double-buffer capable, monoscopic or stereoscopic capable, or a combination of both). The number of visual instances depends on whether the X server is started in monoscopic or stereoscopic mode.