Canvas problems

[Tommytrojan]

I would be happy to upgrade to 3.3.6 if the bug is fixed there. It seems your test with 3.3.5 still had the issue. I'm wondering if jacek could run his test with 3.3.6 on a Windows box. It might be that the problem is only Windows related and 3.3.6 doesn't fix it. Thanks again for looking into this issue.

Cheers,
Tommy

[wysota]

Jacek doesn't have access to 3.3.6 under Windows Qt3 is available on Windows with a commercial licence only, while Qt3/Free port can provide its own bugs here and shouldn't be compared to the Trolltech version.

[Tommytrojan]

So are there two versions? I currently use the commercial version of BlackAdder that comes with PyQt and Qt 3.3.1 (at least the release I have). I know that the Linux version of Trolltech has a GNU license, so is free if the software generated is open. Is there a version which is different from the Trolltech version?

There is one more test that we could perform, if you could run your version (3.3.5) on a Linux box and the problem doesn't show up there it must be something in the difference of the Windows and Linux systems and most likely will not work on 3.3.6 for Windows either.

Tommy

[wysota]

You have seen my version. I get artifacts but other than you.

[Tommytrojan]

I think what you have seen is typical for the kind of problem I have described, so I think we are looking at the same thing here. We know this does not happen on Linux with 3.3.6 but it does happen with 3.3.5 on Windows. We can't test 3.3.6 on Windows, so the only combination to test would be 3.3.6 (your version) on Windows if you have access to it. If not I will probably go ahead and purchase the commercial version from Trolltech. I currently have the commercial PyQt version which comes with a precompiled version of Qt 3.3.1.

Tommy

[wysota]

You can also switch to Qt 4

[Tommytrojan]

Yeah, but since all my drawing code is based on the Q3 QCanvas I would have to use the Q3... classes anyway so there won't be a big difference in that regard.
I hope Trolltech will implement a good/better paint engine in Q4 at some point. I need something that is highly efficient and has a simple interface like the QPainter interface.

Tommy

[wysota]

http://blogs.qtdeveloper.net/archive...ew-sneak-peek/

[Tommytrojan]

Wow, that is great news. I'm certain that problem will be fixed in the new implementation. Does anyone know when a beta of 4.2 will become available?

Tommy

[wysota]

Q3-Q4/2006.

BTW. Jacek suggested that you might have understood that I have tested your code with Qt 3.3.5 under Windows -- that's not true, I tested it under Linux, I don't have Qt 3.3 for Windows.

[Tommytrojan]

Well, if you tested under Linux and the problem showed up with your 3.3.5 version and Jacek tested with the 3.3.6 version and it didn't show there is a chance that it was resolved in between these two releases. I will upgrade in the next few weeks and send a reply to what I find regarding this problem.

Cheers,
Tommy