Adding items in QGraphicsScene is slow

**Grade** · 27th July 2013, 01:05

I'm sorry for the mistake, I meant 10 000ms of course (=10 sec, what I was about to say at first). But that's a lot compared to 500ms.
I mesured what you asked for, and it tells me that there's 0ms between those lines (It must be too fast to detect it). So I think the problem here is adding items.
I should ask a friend to test my application for me. Because I don't care if it's slow for me, really, I just want it to be fast for the others. (Well it would be better if it's fast for everybody but ...)

Well if you have more ideas, don't hesitate, Thanks!

**ChrisW67** · 27th July 2013, 02:01

Sorry, I meant the elapsed time at line 20 since line line 8. Trying to determine if it is the scene building (before line 20) or the displaying (line 20 onward) that is taking the longest.

Which compiler, Qt version and Windows version? Are you using an ANGLE or OpenGL build?

**wysota** · 27th July 2013, 09:13

Originally Posted by ChrisW67

Sorry, I meant the elapsed time at line 20 since line line 8. Trying to determine if it is the scene building (before line 20) or the displaying (line 20 onward) that is taking the longest.

Previous tests seem to indicate it is indexing the scene that takes that time. Which could suggest Grade is using a really old version of Qt

The fun part is that with Qt5 (linux, xcb) the same code takes almost a second to execute on my computer.

**Grade** · 27th July 2013, 15:09

One second ! Wow that's a huge difference indeed.

About my Qt version, I downloaded it recently so I'm under Qt 5.0.2. My OS is Windows XP Pro SP3 and I've got an Intel Core 2 Duo (CPU).
I don't know what do you mean by an ANGLE or an OpenGL Build (I've searched for it but I didn't find anything), I didn't change any configuration so every build setting is the default one.