The Qt 3D Story With Vulkan Should Be Quite Compelling For Qt 6.0

[carewolf]

carewolf , thanks. I was only half-way aware of that. But it is not the solution to our problems. The changes in 2016 - when they changed from LGPLv2 to LGPLv3 caused major headaches on our side and is the major roadblock for us to upgrade beyond Qt 5.9. I'm aware that you might say "that's not supposed to be a problem" - the issue here is that our lawyer needs to come to this conclusion.

That agreement makes me understand why the Qt company puts so little effort into the development of the existing Qt infrastructure and is, on the other hand, all bells and whistles when they announce a new module - which we can't use.

Going with the commercial option is also not a solution for us. We tried that already. As 3diStan already mentioned they have a quite stiff pricing plan (It's comparable to the likes of Presagis, Carmenta and Rockwell-Collins). With the commercial licensing you are bound to the Qt version "you bought". The Qt company is equally lazy with the development of Qt whether you have a commercial license or not. Their support however is OK - not great - but OK. But they ignore you when your license runs out. It would be nice if they would at least politely move your issues to the public bug-list.

Add these problems to the constant problems we have with Qt Creator and qmake and you'll see that I'm fighting a loosing battle against all the others in the company that push for Microsoft.

The company puts a lot of effort into the existing code, maintaince and general improvements just doesn't make the news as often, but yes, the problem is that is not where customer growth is. This got better after the switch to LGPLv3 which meant that at least most commercial embedded users now feel they need to pay.

As for support. When you don't have a license it become similar to community projects, you have to debug your issue more and provide good backtrace and testcases (or get lucky), and issues reported by customers should get reported in the public bug-tracker, all bug-fixing focuses on the public bug-trackers where non-customer bugs also are. The main difference is that if a customer bug is left untouched support will bug the responsible team to look into it.

I don't think you are bound by the Qt version you bought, AFAIK a Qt license is a running yearly fee that allows you to use any version you like. Though if you let your license run out I guess you might get stuck.

[lowflyer]

The company puts a lot of effort into the existing code, maintenance and general improvements just doesn't make the news as often, but yes, the problem is that is not where customer growth is. This got better after the switch to LGPLv3 which meant that at least most commercial embedded users now feel they need to pay.

This is a nice way of saying that they let old paying customers hang out in the rain. And I disagree. I would phrase it this way:

"The company puts a lot of effort in new developments and gimmicks, keeping maintenance and general improvements at a low level. This allows them to make the news more often."

As for support. When you don't have a license it become similar to community projects, you have to debug your issue more and provide good back trace and testcases (or get lucky), and issues reported by customers should get reported in the public bug-tracker, all bug-fixing focuses on the public bug-trackers where non-customer bugs also are. The main difference is that if a customer bug is left untouched support will bug the responsible team to look into it.

When you have a license, you first need to convince the first-responder team member that you really have encountered a problem. The tech-rep that you get forwarded to will deal with your problem in the way that he actually writes the bug-report for you. He also follows it up and directs the attention of the developers to that problem. It usually works out quite well and you get a timely solution - unless they deem the problem as too big - in which case they simply say "no, won't fix".

When your license runs out, they simply go silent on you. They wouldn't even bother to tell you "hey, we're not listening to you anymore". You have to "smell" that now, you need to create the bug-reports all by yourself (which is not that complicated) but you will have no one in the company to follow it up. Other users that have the same problem can help you to build up the necessary pressure to make them address that problem.

I don't think you are bound by the Qt version you bought, AFAIK a Qt license is a running yearly fee that allows you to use any version you like. Though if you let your license run out I guess you might get stuck.

I need to presuppose here that I'm talking about development on the Windows platform. On Linux the whole situation may be different as there are usually complete development environments pre-packaged in the distributions repositories.

Legally, you may be correct. But no. this is not how it works. Once you've bound your user account to commercial licensing, you're no longer able to download the (L)GPL'd versions of it. (well, they make it difficult for you to find the link) And you can download *exactly* the versions that are active during your paid license period. Perhaps the previous versions too. Once your license runs out, you're even locked out of that.

If you want to try out other versions, beta or higher major release versions, you need to create a second user account which you do not bind to the commercial license (I'm not even sure if that is legal). With that second account you finally have the freedom to switch and try versions as you like.

[carewolf]

Legally, you may be correct. But no. this is not how it works. Once you've bound your user account to commercial licensing, you're no longer able to download the (L)GPL'd versions of it. (well, they make it difficult for you to find the link) And you can download *exactly* the versions that are active during your paid license period. Perhaps the previous versions too. Once your license runs out, you're even locked out of that.

AFAIK the opensource and commercial versions are the same. Only the license terms are different. The commercial version is the LGPL version only without the restrictions of LGPL.. There used to be some commercial only modules and features, but those are the ones that are now GPL. I dont think there are any left unconverted. And the installer you use to install Qt with supports downloading the most recent version. Again it might have been different a handful of years ago when the versions contained different things. And the installer should provide you with easy upgrading, but again it sounds like you are complaining about how things were about 4 years ago, before everything was unified to make managing Qt installations simpler.. I could be wrong though, never been a customer myself, but I do test multiple Qt versions sometimes.

I would also suggest large users to use the release or git sources and build from those, that way you can better customize what features you want. You are not getting the full benefit of open source even as a paying customer unless you build from sources It does require some skill especially on Linux if you want what you build to run on many different machines (to avoid depending on too new third-party libs), but with Windows where you just bundled libraries with the app, that is much easier if cruder.

[lowflyer]

AFAIK the opensource and commercial versions are the same. Only the license terms are different. The commercial version is the LGPL version only without the restrictions of LGPL.. There used to be some commercial only modules and features, but those are the ones that are now GPL. I dont think there are any left unconverted.

To be exact: they converted these modules to GPL - not LGPL (!!). Your use of these licenses in the same line of thought is confusing. And I guess that's where the problem is. When you approach the issue as open source developer you can be completely ignorant of these details - or of any limitations - because they mostly do not apply to you. But If you are a commercial company, it is the license that blocks you from doing certain things. It does not matter whether the versions are the same or different or on the moon.

And the installer you use to install Qt with supports downloading the most recent version. Again it might have been different a handful of years ago when the versions contained different things. And the installer should provide you with easy upgrading, but again it sounds like you are complaining about how things were about 4 years ago, before everything was unified to make managing Qt installations simpler.. I could be wrong though, never been a customer myself, but I do test multiple Qt versions sometimes.

You missed my point. You claim that it is easy to test various Qt versions as a "non-customer". Why is it so much more difficult when you *are* a paying customer??? This made us to completely switch to LGPL in development - despite the commercial license. It's also not about the Qt installers. We create our own installers anyway.

I would also suggest large users to use the release or git sources and build from those, that way you can better customize what features you want. You are not getting the full benefit of open source even as a paying customer unless you build from sources It does require some skill especially on Linux if you want what you build to run on many different machines (to avoid depending on too new third-party libs), but with Windows where you just bundled libraries with the app, that is much easier if cruder.

As I said before, we're on Windows. We're happy with the customization we can achieve with the LGPL. To build from source is not the point. We did that many times but we found it completely unnecessary in our case. And it would make the deployment more difficult because of the LGPL. But before we would consider this you would have to point out exactly what you mean with the "full benefit". We're commercial you know.

[carewolf]

To be exact: they converted these modules to GPL - not LGPL (!!). Your use of these licenses in the same line of thought is confusing. And I guess that's where the problem is. When you approach the issue as open source developer you can be completely ignorant of these details - or of any limitations - because they mostly do not apply to you. But If you are a commercial company, it is the license that blocks you from doing certain things. It does not matter whether the versions are the same or different or on the moon.

The GPL is more lenient than a commercial only license, and the GPL modules we are talking about used to be commercial only. So the conversion only allowed more users, it didn't block anybody.

If you are a commercial company just pay the license, or use something else and pay _their_ license.

[lowflyer]

The GPL is more lenient than a commercial only license, and the GPL modules we are talking about used to be commercial only. So the conversion only allowed more users, it didn't block anybody.

A commercial user that is moving towards LGPL *is indeed blocked* by the GPL. You again assume the position of the Qt Company. I've tried to explain that commercial didn't work out well for us.

... just pay the license ...

This is the most used silly fallacy of software managers. Licenses usually have a price on top of the price tag.