AGNEW@VCUVAX.BITNET.UUCP (08/10/87)
Dear all in Netland:
Here is an awesome and simple little trick for you SMG hackers if you have
written modular code doing lots of updating in only a few places in your
program. PLEASE NO HACKER FLAMES!!! I'M NOT A CRACKER!!!
When you are placing lots of data onto a screen onto a virtual display
using SMG, you can approximately triple the speed of a screen update by
using the SMG$BEGIN_DISPLAY_UPDATE call just before the section of code
doing the updating, and SMG$END_DISPLAY_UPDATE just after. No one will
notice that interactive actions will have been interrupted for an instant,
and the screen will blast into view at max warp speed!!
Interestingly enough, whether you set the display to scrolling or not,
these SMG routines are smart enough to determine whether scrolling will
accomplish the screen update faster, whether to do it or not. The display
will scroll by itself without any coding effort.
There are SMG$BEGIN_DISPLAY_UPDATE and SMG$END_DISPLAY_UPDATE calls
for the entire pasteboard, but these DISPLAY seems to be the most efficient
since you want to put this where you will have the most impact. The manuals
say that using these calls will cause your program to interact funny with
the user, i.e., the user will not see what they type or something like that.
So, if you have a ten line loop painting a menu, put these calls in, and
take cover!!!!!
Jim
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/Jim Agnew, Programmer/Analyst | DISCLAIMER: \
/ Medical College of Virginia | If anyone is caught using either my |
/ Virginia Commonwealth U. | hints, info, or code, I will disavow |
| Division of Neurosurgery | any knowledge of their activities! |
| Box 508, MCV Station | I think this info is correct, but if |
| Richmond, Va 23298-0508 | it is not: |
| BITNET: AGNEW@VCUVAX | "This tape will self-destruct in |
| Ma Bell Net: +1 804/786-8601 | five seconds. Good luck, Jim." |
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| Space for cute saying here but I haven't been able to think of one... |
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