| layout | title | permalink |
|---|---|---|
page |
Q24201: Flipping and Swapping Screens |
/pubs/pc/reference/microsoft/kb/Q24201/ |
Article: Q24201
Version(s): 1.00 1.10 2.00 2.10 2.20 2.30
Operating System: MS-DOS
Flags: ENDUSER |
Last Modified: 9-AUG-1989
Question:
What is the difference between flipping and swapping in CodeView?
Response:
Both are ways of maintaining two alternate screens for display on
one monitor. The difference is in the way the task is accomplished.
When swapping is selected, CodeView allocates a 16K buffer (a 4K
buffer for a monochrome adapter) to hold the alternate screen. When
the other screen is required, CodeView swaps the screen into the
display buffer and places the other screen into the storage buffer.
Swapping takes memory and time, but it does not have the limitations
of flipping.
Flipping uses the video-display pages of the graphics adapter to
store each screen of text. When the alternate screen is required, the
other page is selected. Flipping is much faster than swapping and does
not require the 16K buffer. However, it cannot be used with a
monochrome adapter, or with programs that display graphics or use the
video pages.