Scenery Compatibility

I had a conversation with a third party developer the other day - he offered to sign a non-disclosure-agreement (NDA) and wanted to know: would custom scenery he made for X-Plane now keep working with the next major version?

Well, no NDA is necessary for that. The simple answer is: yes! (A more complete answer is: if you use the current file formats and not legacy formats from 9 years ago, then yes.) Here's a quick review of how long the various scenery and modeling file formats have been supported:

• DSF: 5 years
• OBJ8: 5 years
• OBJ7: 7 years
• ENV: 9 years
• OBJ2: 9 years

With X-Plane 8 we rewrote a lot of the rendering engine - since then, rendering engine enhancements have been incremental, building on what we have. The next major version will be like that too: the new version will do more than X-Plane 9, but it's not going to drop existing capabilities.

So if you model a building with an OBJ or model a terrain area with a DSF, I expect that it will work unmodified with the next major version.

Modeling Formats in Detail

X-Plane 9 supports 3 revisions of the OBJ file format (X-Plane's modeling format):

• Version 800, which is the current version. Introduced with version 8, the OBJ800 format has been extended heavily, but the format was never changed, so original version 800 objects are not incompatible.
  
• Version 700, which was used with version 7.
• Version 2, whic hwas used for most of the X-Plane 6 run.

The next major version will clearly support version 800, and will probably support version 700 as well.

Do not make new objects in the version 700 format! This format is obsolete, supported only for legacy purposes, and is an inferior format.

We may drop support for version 2 objects - I haven't seen user content with a version 2 object in a very long time. Version 2 objects date back to a time when every polygon was expensive, so content authored in version 2 is likely to look, well, ten years old.

If you do have version 2 content, you can use ObjConverter to convert it to version 800 format. (ObjConverter will also convert version 700 OBJs to version 800.)

Scenery Formats

DSF has been our scenery format for five years now, and will continue to be so. DSF has not had any format revisions - new features are supported by allowing DSF data to be tied to new art asset formats.

I do not know if we will support ENV in the next major version. Supporting ENV is relatively trivial in the code, but whenever there is a bug, we have to fix it in the legacy ENV code as well. ENV supports a 500m terrain mesh, which is completely obsolete by today's standard.

Do not make new content in the ENV format! Like OBJ 2 and 700, it is a legacy format for backward compatibility.