SGS_CLRBL

Clear block

ACTION:
Clears specified area of screen if this can be done without affecting the rest of the display surface.
CALL:
SGS_CLRBL(x1,x2,y1,y2)
INPUT PARAMETERS:

x1,x2,y1,y2

R

Extent of area in world coordinates.

GKS EFFECT:
The specified area is cleared. The technique used depends on the workstation type.