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graphics and bitblt questions

Although this doesn't have much to do with borland pascal in particular, it
has something to do with programming in general, and I think that many
people in this newsgroup would know the solution to my problems.  I program
mostly in dos, and only for less than a year in it.  I was wondering what
does the term bitblt mean?  I have seen it in windows and dos newsgroups.
How exactly does it work, the exact specifications of it, such as how does
it work, how can I implement it the fastest (speed wise for my programs) in
a 16-bit application?  I am asking this because I need to know it for my
(small) graphics library that I'm making. I program mostly in turbo pascal,
but if somebody here can explain everything I need in c++ then I understand
it also.  I'm tired of using the slow and cumbersome borland's graphical
interface (egavga.bgi).  However, I found some procedures such as xorput,
orput, copyput, etc. in the .bgi that I believe are somewhat faster in doing
animation than simply drawing a picture, putting black pixels all over the
original spot, drawing it somewhere else, erasing that with black pixels....
you get the picture.  If anyone in here has experience with bitblt,
orespecially if you have experience with dos graphics, then please email me
or reply to this newsgroup with help.  Thanks for your time, and I look
forward to all constructive replies.  Also, if anyone knows the fastest
routines/algorithms for basic graphical functions in dos, then I'd be more
than happy to discuss then with you.  If anyone is on msn messenger and
knows something about graphics in dos, then I wish I could ask you some
questions.  Also, if anyone knows the FASTEST way to put a pixel in a 16-bit
app, I would like to know it also.  I also need to know how to change to the
following video modes:
320x200x256,320x240x256,640x480x256,800x600x256, although the last one's not
as important.  I also need to know how to change make to text mode (80x25).
Any help on these topics would be much appreciated.
p.s.  I have the allegro {*word*143} library, and djgpp, and they are both
excellent resources.  However, I'm trying to create my own from scratch
(nothing like allegro of course) so that I have a better understanding of
how it all works.  Thanks for your time all, and I hope that noone's pissed
at me for putting this in a pascal newsgroup when it should be in a graphics
for dos newsgroup (is there such one?).
 

Re:graphics and bitblt questions


Quote
In article <3a763...@leia.ktsnet.com>, Cody wrote:
>Although this doesn't have much to do with borland pascal in particular, it
>has something to do with programming in general, and I think that many
>people in this newsgroup would know the solution to my problems.  I program
>mostly in dos, and only for less than a year in it.  I was wondering what
>does the term bitblt mean?

Bitblt are functions that are mostly hardware accelerated (the 2D
acceleration kind, which emerged with later ISA VGA devices), that can move
entire blocks, with several modes. (corresponding with the principles behind
xorput, andput etc, and a lot more of those)

 I have seen it in windows and dos newsgroups.

Quote
>How exactly does it work, the exact specifications of it, such as how does
>it work, how can I implement it the fastest (speed wise for my programs) in
>a 16-bit application?

Since it is hardware dependant, you either have to tackle it on a per
videocard basis, or via an API.

The per videocard base is *a lot* of work, and not all data needed may be
available to the public.

The API case leaves you with VESA (if it supports such beasts), since
DirectX/OpenGL are hard to reach from dos.

Quote
>app, I would like to know it also.  I also need to know how to change to the
>following video modes:
>320x200x256,320x240x256,640x480x256,800x600x256, although the last one's not
>as important.

There must be numerous VESA units for BP on the net. Try a search engine

Re:graphics and bitblt questions


JRS:  In article <3a763...@leia.ktsnet.com>, seen in
news:comp.lang.pascal.borland, Cody <co...@ktsnet.com> wrote at Mon, 29
Jan 2001 21:38:42 :-

Quote
>Although this doesn't have much to do with borland pascal in particular, it
>has something to do with programming in general, and I think that many
>people in this newsgroup would know the solution to my problems.  

Already answered elsewhere.  Please do not multi-post.

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