afphoto files saved by Photo 2.1 Beta cannot be opened by Photo 2.0

[Steve Ballard]

Attempting to open Photo 2.1 (Beta) file with Photo 2.0 gives a message that the file contains features from a later version and will not open it. While this is reasonable and even expected between major versions I find it strange that compatibility all across 2.x doesn't seem possible.

I stumbled across this when working with several layers and embedded RAW. I then checked it out with pixel layer and this being the only layer (as simple as I could imagine) and the same compatibility issue is there.

Note, I was able to copy each layer from 2.1 beta into 2.0, one layer at a time creating the same setup.

Is this the intended or is it a bug?

 

[walt.farrell]

It is intended.

The version numbering looks like this: v.r.minor.build

When you try to open a file, the version you're using to perform the Open must have a v value >= the value of the program that Saved the file, and an r value >= the value of the program that Saved the file.

Thus, in the past, 1.7 could not open files produced by 1.8, and 1.8 could not open files produced by 1.9. Thus, 2.0 should not be able to open files produced by 2.1. That second number (7, 8, 9, 0, 1) determines the downward compatibility, and only changes when the files are no longer downward compatible. However, this may not happen immediately, so I think the initial 2.1.0.nnnn builds were still compatible with 2.0. The same thing happened initially between 1.10 and 1.9, I think.