Skandha4 uses a graphic-terminal driver library to access the workstation graphics. This means that by writing a new driver, you can use all of Skandha4's 3D capabilities on your favorite high performance graphics workstation, even if it doesn't support the SGI-defined OpenGL (Open Graphics Language) that the current driver uses.
This manual is primarily oriented towards doing 3-D raster graphics in Skandha4, so we won't document the older 2-D functions heavily, or encourage their use particularly.
Please note that most 3-D graphics in Skandha4 is done via :DRAW messages to a camera, with very few calls directly to the GT module. (CAMERA does internal calls to GT to generate the image, of course.)
In fact, other than for user I/O via mouse or keyboard, the only direct GT calls a normal Skandha4 application is likely to make are:
;; Initialize to usual mode: (gt-graphics-mode) ; Enter graphics mode. (gt-set-double-buffering-is-on t) ; Select double-buffered mode. (gt-set-zbuffering-is-on t) ; Ask for hidden-surface removal. ;; At beginning of each screen redraw: (gt-set-color '(0 0 0)) ; Set current color to black. (gt-clear-viewport) ; Clear screen to current color. ;; Redraw code here, probably including a (:draw camera ...) ;; At end of each screen redraw: (gt-swap-buffers) ; Make new frame visible to user.
So ... please don't get too excited or depressed over the number of calls supported by the gt!