I suspect it's the latter, and some people here are simply telling each other what they want to hear to justify the "2nd class citizen" problem.

Indeed. Looking through my collection, most games don't have or need "delta patches" at all. Many games with either outdated offline installers, or games like like Divinity Original Sin where the game is up to date but the newest offline installer version is buggy have remained unchanged for years. Not fixing this stuff is not a "storage space" problem, it's a laziness problem...

No because the Galaxy repository only store the difference between a version to another, not the full installer. (i.e. if you have only 1MB that changes in a 20GB game between version 1 and 2 then only 1Mb is stored and not twice 20GB)

Technically it would be possible to have a system that dynamically generate an installer from a specific version using Galaxy repository, but Gog probably decided that the demand was not sufficient to justify the development and maintenance of such a feature.
That would be true only if the offline installers were created dynamically, as in, when you click the download button, the system fetch the data from the Galaxy repository and create a new installer from scratch that is not actually saved on the server.

It's not the case here, even if the offline installer are created from the same source than Galaxy downloads, they are created before hand and saved on the server, so if they wanted to have multiple versions they would need to either save all the versions or decide to use an old version as "reference" and create incremental patchs from it.

The "storage space problem" was only created in 2014 by Galaxy doubling up on logistics under the guise of "simplification" in the first place. Prior to Galaxy there was no need to store everything twice "because muh client". A far saner solution would have been to have only offline installers (inc delta patches) logistical path, but create a script per game that automates the process of Galaxy downloading offline installers (including handling multi-part installers transparently), fetches and applies the correct delta patch based on detecting installed game version, then installs them with a /silent switch, then at the end offers to either delete them or back them up (maybe even automate that based on a Galaxy preference). Only GOG could think of doing absolutely everything twice over via two different logistical branches, and then deliberately degrade the one directly related to GOG's Unique Selling Point as "progress".

Edit: And I'd love to know how much time was wasted having to unnecessarily repack the whole GOG catalogue offline installers to include Galaxy metadata (.hashdb, .info, galaxy.dll, etc, files), having to repack multi-game installers into individual ones, or the endless stream of Galaxy related "updated internal installer structure, no change to game save files" changelogs which also only sprang into existence in 2014. It's an insane amount of "make work" that's entirely self-inflicted by Galaxy for which offline installers hilariously get the blame for being a 'burden'...

And before Galaxy there was no rollback possible at all and very little delta patches (most of the time you have to re-download the full game).

No that wouldn't work. First it would make installation repair impossible, if some of your install is corrupted then it would mean download the last full installer and reapply all the patches instead of just downloading the delta to fix the issue. Same thing if you want to rollback to a previous version, instead of, again, only downloading the delta, it would also mean download the last full installer before the desired rollback version and download and re-apply all the delta patches.

As I said in my previous post, IMHO, the only way to avoid storing twice everything would be to create the installers "on demand", or an hybrid approach, where the latest version is stored and if you want a rollback version then it creates a zip or a rar on demand with the right files.

Which simply meant that if a game was buggy and there was no way to "roll back", the newest version would be more likely to get fixed rather than abandoned like D:OS 1, if GOG actually want to continue to sell it...

If you had Galaxy back up the installers on the first install, there would be no need for constant full re-downloads for a reinstall. That's the whole point of offline installers... I find it hilarious this stuff is supposedly "impossible" for GOG, whilst Steam users can backup their game install folders, and if something breaks, they can delete the game folder, restore it from a backup and re-authenticate often without needing to re-download everything... I also can't say "corrupted installs" is some major widespread common issue as I never seem to see the problem on offline installers outside of a small handful of notoriously buggy games, impending HDD failure or people randomly deleting files (which will break anything). If people are seeing hundreds of games in their collection get corrupted en-masse, then I'd love to know what they're doing wrong...

That means that if you install a 50GB game you need 50GB for the game plus potentially 40GB more for the installers, plus a couple of GB more for the extra patches... No it's not anything practical that anybody would want to use, one of the main reason peoples uses client for updates is to avoid this sort of stuff.

Steam backup, simply backup the installed folder, nothing else they don't backup any "installer" or anything, you can do the same with Gog, just Zip your install folder. And once you "restore" your backup, Steam compare the local installation with the server repository and download the differences if any... same way Galaxy works.

It can happen easily if a patch fails applying, and depending what file it was patching simply restarting the patch might not be enough and require you to reinstall from the original installer. There is a reason why when you ask for support for a game one of the first thing support asks you is to either try to reinstall the game or launch an installation check.

For those who don't want / like clients though, far from being "encouraged" to use Galaxy, that stuff increasingly sounds like one giant "anti-advert" for not buying or pre-ordering any new game on GOG at all until the devs have actually finished it. I think some people are so wrapped in over advertising Galaxy that they miss the obvious - there are two groups of people making GOG offline installers (GOG themselves and "scene groups", and from what I've heard often 'repack' Galaxy versions faster than GOG themselves seem to manage internally). It would be remarkably stupid of GOG to keep degrading them and in the process of overly-pushing Galaxy end up accidentally pushing people back towards the same thing the original founders of GOG was enticing them away from on the very same grounds of "Paying customers should not get a second class experience vs pirates..." So whether it's "technically difficult" or not to have 1 vs 2 logistical paths, it's still in GOG's interest to start fixing the outdated / buggy installers.

Do you mean entirely, or just on the browser(i.e. one could still download the installers and back them up via galaxy)?

If the latter, tbth I might be slightly tempted to install galaxy. If the former, it'd likely depend on price(I do buy some steam games on rare occasion if the price is decent enough....especially if they are already "DRM free").

That(less work for me to backup games), the community(there are still a number of good sorts here, whom I love to chat with about various topics), and a few other factors.


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This bit, and also the rest of this post i'm replying to: *slow clap* well said

^ That's been my attitude for the past couple of years now. Any new interesting game now doesn't get instantly bought / pre-ordered at full price like it used to, instead it just gets placed on a wishlist and monitored. If GOG wants me to pay them 50-75% less money for games due to the time it takes both developers to finish it + GOG to update the offline installers, I'm happy to save the money...

Maybe, if we were fine with the idea that the base offline installer is always some old version of the game, which you have to manually patch with one or more patches after installation.

At least I'd prefer the offline installers are the latest version, and the patches are just for those who have already installed an older version earlier. Then I could skip downloading the patches altogether.


EDIT: Like Gersen pointed out (I think), one way to "solve" the problem would be that you there wouldn't be any separate prepackaged offline installers, but instead you'd have to make your own GOG game "installers" (or rather, zip compressed installation directories) as follows:

1. You download and install a GOG game with the Galaxy client. At this point you can decide which version of the game you install, I presume (or how that rollback feature works, not sure as I don't currently use Galaxy).

2. There is a magical "backup" button in Galaxy, a bit similar as in Steam, that will compress all the installed files for that game into a .zip or .7z or a self-extracting .exe file, possibly accompanied by some crude installation/uninstallation scripts that also take care of installing some dependencies, registry settings etc. that the game may need, if run without Galaxy on another computer.

That way you would have to create the offline "installers" of your GOG games with the Galaxy client yourself, AFTER you have downloaded and installed the game with it. However, I presume many offline installer users wouldn't be happy with such a solution because then they would probably be forced to use the Galaxy client to download their games, even if the game could be played without Galaxy ever after.

I am not fully sure personally if I would be fine with such a "solution". At least it would make it quite hard or even impossible to mass-download lots of, or all of, your games, gogrepo-style. You would really have to download, install and process each game individually, in order to obtain the "offline installers" for them.


EDIT2: Well, maybe it would be possible to create also a mass-download tool or feature in that case as well, but it would be rather complicated. Something like:

- The tool checks, one game at a time, from your local "offline zip" archive whether you have that game downloaded and zipped already, and whether it is the same version as on the GOG server.

- For those games that are missing or not up to date, it would, one by one, download and install the game, make the backup copy of the installation, and then uninstall the game.

Yeah, I guess it could work... At least your PC and SSD/HDD drives would get a full workout, installing, compressing and uninstalling hundreds or thousands of games, one by one.

Wasn't the creation of offline installers supposed to be pretty much automated nowadays, if and when the developer applies an update to the main branch, or something like that?

I guess someone will soon point to that GOG dev web page where it says something like that...

Here you go:
https://docs.gog.com/offline-installers/

Then we could have this:
- Latest full installer.
- Oldest installer available for rollback through Galaxy.
- Patches for the versions in between.
So users will get the same options regardless of whether they use Galaxy or the offline installers, just that the offline ones will need to apply patches incrementally if they want a version in between the oldest available and newest, and will do away with requirements to store full installers for each of those versions. And will also solve another issue, ensuring that patches are available for multiple versions so those who have skipped updating one or two will be able to do so without needing to reinstall.
Say WHAT???

PS: Anyone else aware that the current installer and latest patch for Hero-U lead to a 404?

Not sure if a third-party tool could do it too (including installing GOG games similarly like Galaxy does), but I presume just using a web browser would be out of question because the "offline installers" would have to be created client-side on the fly... unless there was some quite complicated javascript thingie running doing all that, I guess...