• Which the release of FS2020 we see an explosition of activity on the forun and of course we are very happy to see this. But having all questions about FS2020 in one forum becomes a bit messy. So therefore we would like to ask you all to use the following guidelines when posting your questions:

    • Tag FS2020 specific questions with the MSFS2020 tag.
    • Questions about making 3D assets can be posted in the 3D asset design forum. Either post them in the subforum of the modelling tool you use or in the general forum if they are general.
    • Questions about aircraft design can be posted in the Aircraft design forum
    • Questions about airport design can be posted in the FS2020 airport design forum. Once airport development tools have been updated for FS2020 you can post tool speciifc questions in the subforums of those tools as well of course.
    • Questions about terrain design can be posted in the FS2020 terrain design forum.
    • Questions about SimConnect can be posted in the SimConnect forum.

    Any other question that is not specific to an aspect of development or tool can be posted in the General chat forum.

    By following these guidelines we make sure that the forums remain easy to read for everybody and also that the right people can find your post to answer it.

Comparing MDL Files

scruffyduck

scruffyduck

Administrator
Staff member
FSDevConf team
Resource contributor
Messages
34,981
Country
unitedkingdom
Arno

Given that EZ-Scenery has set off a bit of a rash of recompiled libraries using standard and other objects I can see the same object turning up a number of times with different GUIDs. I'm not sure if that matters or not. Does copyright lie with the mdl file or the library? mdl file I would guess.

Anyway I want to include the ability to compare mdl files in my object manager program. Since re-compiling a library with new GUIDs won't change the mdl I am planning to do a bitwise compare of files or use a hash code generated for each mdl. Does that sound sensible? I guess if your MDL Tweaker program is used then the mdl is changed in any case?

thanks in advance
 
Hi Jon,

MDL Tweaker does indeed write a totally new file, as you want to apply some tweaks to it :). But if you save without making changes, the file will remain the same of course.

I don't think that we should see many duplicate objects. Extracting and distributing a MDL file that is not your own is against copyrights if you ask me. So I would never advice people to do so. It is the same as decompiling a BGL file to hack it.

What would you want to do with the knowledge that two files are the same? I don't think it tells us much. We can't remove one of the two without having to change all BGL files that call this library as well.
 
I agree - personally I would not want to decompile a bgl so that I could remove the mdl objects and re-package them in new libraries with new GUIDs - but I think some people are doing that so that they can re-categorize the objects into groups that better suit their needs. I want to do that as well but my method involves creating new reference files which programs like Sbuilder or RWY12 can use and present me with the categories I want without having to change the underlying libraries in any way

However If I am managing a catalog of objects which are provided by different people in different libraries then I would wnat to know if the same object existed in two libraries. I would only want to reference one of them when degising scenery.

Having said that you must excuse me if my thining is muddled - I am new to working with FS9 mdl objects and still feeling my way as to how they work
:)
 
Hi Jon,

Yes, I think your approach is much better. SBuilder and Rwy12 also allow you to categorise like that. Unfortunately EZ-Scenery does not, it just scans all available library files. The only reason to decompile I can understand (although I do not agree) is to remove the geo-locking on some default libraries.

Your idea of the comparison starts to make sense to me as well. Could indeed be useful. I guess a simple bytewise comparison of the two objects would be fine in that case. Or maybe to improve the performance you could start with simple checks like are the bounding boxes and the texture lists identical.

And don't worry about all the questions and suggestions. They are good to keep me awake for new ideas :). I might know a lot about the MDL format already, but discussions like this also help me to learn even more.
 
Thanks Arno.

I was wondering about EZ-Scenery and I had forgotten for the moment that you made the library manager :o . I have not tested it yet but does EZ-Scenery take the category lists it displays from the text file produced by your library manager? if so could I create a reference file not linked directly to a bgl and will that display the objects included in the text file even if they are located in different libraries? If I understand your comment above correctly then it would seem that you can't
 
Hi Jon,

I must say that I don't know all the details of EZ-Scenery as I made only the library manager. But as far as I know EZ-Scenery only uses the names of the library BGL files to categories the files in the GUI. So you can not make different categories yourself.
 
Hi Arno

Thanks - that is what I suspected
 
You must log in or register to reply here.
Back
Top