"marcin komorowski" <marcin.komorowski@canrem.uucp> (06/20/91)
TO: GLEN FORD
Original subject: Computer Graphics Metafile
Hellow Glenn
You recently wrote in this conference:
GF>Original subject: computer Graphics Metafile
GF>I have recently been asked by my boss to do some research on
GF>CGM format images. What I would like to know is what kind of
GF>low level graphics libraries there are for DOS/UNIX/OS2?
GF>I need to be able to, obviously, display CGM format images, as
GF>well as any nifty things, like pan and zoom, rotation ,etc..
GF>Is there ANY library out there that does any of the above?
GF>I am interested in commercial, or public domain.
GF>I am totally new to CGM, so any research material available
GF>would be greatly appreciated..
Basically CGM files are what's called "vector oriented" files, just like
PIC format. It is different from PCX, TIF, TIFF and other so called "bit
mapped files." The latter can basically be thought of as if you would
put a dense grid on an picture and assign each small section of the grid,
popularly called pixel, a specific colour, this way storing a
approximate immage of the immage as a series of numbers representing the
colours of the pixels in sequence.
Vector oriented files are very superior and completly different from bit
mapped files. The immage is stored as a series of "objects" with
specifications of their type, location, and relative dimentions attached
to them. The information relating the object's location is specified as
a vector coordinates, and that's the reason for the name "vector
oriented." The reason for the superiority of this type of graphic files
is that the resolution is never lost no matter hom much one zooms into
the immage and they are very easy to rotate, scale and manipulate.
This is how much I know. I myself am on a serch for the same things you
are looking for, but I was not very succesfull till now. I've been
looking for libraries for over a month and the only thing I found so far
is a company that sells specification for all kinds of computer stuff.
The company's name is Global Engineering. The phone number to their
sales office is (212) 642-4900 or toll free 1-800-454-7179. I called
them and they do have the specification for CGM files. If you are
willing to write your own program for handling these files they can sell
the specs to enyone for $90. The CGM spec's number is ANSI X3.122-1986.
Having this number with you when you order makes the transaction much
easier, because they have thousands of specs there and it takes time to
find the one you are looking for. I did not buy the specs, because
unfortunatelly I don't have the money at the time, but I hope this helps
you.
I'm going to continue my reserarch, and I'll let you know if I'll find
something. I woul appreciate if you could tell me if you'll find
something.
Oh ya! If you wnat to display or print CGM files Word Perfect v5.1 and I
believe also v5.0 can do it for you. I am not sure but I think that
Borland's Quattro Pro v3.0 (great spreadsheet package) can read and
print those files as well. It also has a very powerful annotating
facility for it's graphs, and you can actually design vector oriented
graphics using it and then save it as a CGM file.
Well, that's all I know. I hope I could be of help to you. I'll be glad
to hear if you find out anything more.
Marcin Komorowski, CRS,
Ajax, Ontario, Canada
---
? DeLuxe? 1.12 #8081 ? SMILE - it does not hurt, but it can save the day!
--
Canada Remote Systems. Toronto, Ontario
NorthAmeriNet Host