Control of Graphics and Text Windows
Display Control
Getting User Input
AutoLISP provides functions that control the low-level graphics and allow direct access to the AutoCAD graphics screen and input devices.
The grtext function displays text directly in the status or menu areas, with or without highlighting. The grdraw function draws a vector in the current viewport with control over color and highlighting. The grvecs function draws multiple vectors.
NoteBecause
these functions depend on code in AutoCAD, their operation can
be expected to change from release to release. There is no guarantee
that applications calling these functions will be upward compatible.
Also, they depend on current hardware configurations. In particular,
applications that call grtext are
not likely to work the same on all configurations unless the developer is
very careful to use them as described (see the Customization Guide)
and to avoid hardware-specific features. Finally, because they are
low-level functions, they do almost no error reporting and can alter
the graphics screen display unexpectedly (see the following example
for a way to fix this).
The following sequence restores the default graphics window display caused by incorrect calls to grtext, grdraw, or grvecs:
(grtext) Restores standard text
(redraw)