| From: | Joris Kempen |
| Date: | 25 Apr 2001 at 13:09:09 |
| Subject: | Re: Datatypes |
Hello Oliver
On 23-Apr-01, you wrote:
> Correct. These files contain the actual program code that is executed
> to decode/read different filetypes.
Good point from me :)
> Yep - the files in this directory are more commonly known as datatype
> descriptors. These contain the filetype recognition code for each
> datatype, a group id (e.g. picture, sound, text, etc) and also a "pointer"
> to the datatype in SYS:Classes/Datatypes which handles that filetype.
But this probably means that a datatype descriptor points to a fixed
datatype in Classess/Datatypes.
The akJPG descriptor will point to the akJPG.datatype in Classess/Datatypes
or not?
> For example... say you run something like "multiview test.jpg". The
> datatypes system will then scan it's filetype database (built-up from
> the files in DEVS:Datatypes) and when it finds a matching descriptor,
> it'll then pass the info onto jpeg.datatype (or whatever name was
> defined in the descriptor),
Yes i was right, the descriptor and the datatype itself is fixed to each
other.
So when I install a new datatype I install the descriptor and the datatype
that belong to each other...
> You can keep as many different files in SYS:Classes/Datatypes as you wish.
What should you do that?
> What matters is the files in DEVS:Datatypes - generally, you should not
> have more than one descriptor in there that matches a certain type of
> file. So, if you had two different JPEG descriptors in there (e.g.
> JFIF for akJFIF and JPEG for WarpJPEG),
But now I'm using the Picture.datatype from VGR that comes with CGFX4, this
one doesn't handle all my JFIF pictures AFAIK, should i also install the
akJFIF datatype, or will they override each other?
What i hate about some picture datatypes i used is that they open there own
screen, i really hate this because i normally use Cyberwindow for viewing,
and then it's not streamed to a window but to a screen.
Is this because my JPG datatype isn't "good enough" for this file and akJFIF
takes over or,
is it that Cyberwindow internal decoding isn't "good enough" for this file
and akJFIF takes over.
I really prefer datatypes that don't open there own screen...
> No, because programs can specify which types of files (matching the
> group ids given in the datatype descriptor files) they want to be
> able to load. So, something like CyberWindow will specifically ask to
> only receive pictures from the datatypes system. Whereas, Multiview
> does not impose any restrictions and can therefore be used to view all
> types of files (for which there are datatypes available).
OK this makes sense to me....
> Just install the ones that you think you'll need... Generally, the
> newer the datatype is, the better it will be (i.e. a newer JPEG
> datatype, is better than using some ancient old one form Aminet :)
To be honest i only found quit old jpg datatypes. Only the akDatatypes are
being updated AFAIK. Considering I have a 68k machine and not a PPC :(
>
> Shameless plug coming up :) Click on the URL below, and you'll find some
> great datatypes for JPEG, PNG, BMP and PSD images.
>
Thanks I'll take a look around there.
Regards
mailto: trekker@studenten.net
webmaster: www.detrekkers.com
Quote carefully and read all ADMIN:README mails
Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/