home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
World of Shareware - Software Farm 2
/
wosw_2.zip
/
wosw_2
/
CPROG
/
MS.ZIP
/
ARC4_2.CHP
< prev
next >
Wrap
Text File
|
1993-06-15
|
2KB
|
47 lines
%
#EF
#T15,1,Chapter 4 Animation Pg. 2
#HS,1,4,80,25,11,1
#C4,R5
~Y~I
~W~IFrame Animation~Y~I
Frame animation is done by creating several pictures, or |frames|, that can
be flashed on the screen at high speed to produce the appearance of motion.
#WN
#C4,R11
This is the technique used to produce cartoons. The frames are drawn one by
one, then photographs are shot of each frame. The photos are strung
together and shown at a rapid rate, producing the illusion of motion.
#WN
On a computer, we can store each frame in memory or on the disk and display
them one at a time on the screen. Each frame is stored in memory on a
different |page|.
#WN
#C4,R19
On the EGA or VGA, there are multiple pages of memory available for use. If
we want to, we can load or draw images onto one or more of the pages that
are not currently displayed and then rapidly flip from page to page to
animate a picture. Most graphics images, however, are so large that it is
difficult to load them fast enough to keep the animation going.
#WN
%
#EF
#T15,1,Chapter 4 Animation Pg. 3
#HS,1,4,80,25,11,1
#C4,R5
~Y~I
Unfortunately, the CGA has only ~Yone page ~Y~Ito work with, so frame animation
isn't as useful as on other adaptors. Multiple pages can be simulated by
allocating memory in the user program space, which is the 640K we normally
use for our DOS programs. However, with the CGA almost dead as a commercial
option, building a paged animation system for such a low resolution adaptor
hardly seems worth it.
#WN
#X