Infralution Support

[JakobM]

Hi and thanks for a nice control!
I am trying to use a virtual tree to display approx. 1000 items with 6 columns, 1 main column and 5 columns using CheckBox as a CellEditor (Display always).

Loading/creation works just fine, but when trying to scroll (both vertical and horizontal), well, you'll better get a cup of coffee

Any idea on how to fix this problem?
Is it (almost) impossible to use checkboxes in column when having a fairly large amount of rows?

Thanx in advance,
Jakob

[Infralution]

Have a look at the File Browser sample that uses Display Always CheckBox editors. Does it run slowly on your machine as well? On my fairly old laptop this scrolls without any perceptible lag. If not maybe you could send us a zipped sample project (to support@infralution.com) so we can see what the issue might be.
_________________
Infralution Support

[Guest]

Thanks for your quick response.
Yes, the File Browser sample also runs very slow.
My computer is fairly new, Pentium 4 @3.2GHz (Dual Core), 2 GB Ram, NVidia Geforce 7600 GS.
OS: Microsoft Windows NT 5.1.2600 Service Pack 2

It's pretty much useless for me to use checkboxes with current performance. I have encountered the problem with checkboxes as CellEditors. Everything else works just fine without any glitches.

I have tried the sample application on three different machines, all showed the same problem...

When scrolling horizontally, it is clearly visible that the repaint of the checkboxes happens before everything else. Like this:
1. New checkboxes are drawn over the old image (the old ones are still visible)
2. Everything else is repainted without any visible delay or flickering.

I have tried with and without XP themes,
with and without hardware acceleration.

[Infralution]

[JakobM]

Yes, I am running XP, SP2 and Virtual Tree 3.1.

Well, I might have exaggerated slightly, but I would definitely call it unusable. I estimate each repaint operation (one mouse click) to run approx 0.5 seconds, which gets quite annoying when holding the mouse button down (scrolling continously). Things get even worse when grabbing the vertical scrollbar handler to reposition the vertical scrollbar position in a large tree, here it is very difficult to navigate since I have to estimate the correct mouse position, wait for the control to repaint and adjust the position again etc.

Good news though! Or some news at least...
I have now run the sample on 8 different machines and found 4 machines that was able to run the sample without too much hickups. Still, I noticed visual repainting but not as much as on the other machines, and although a bit annoying definitely usable.

CPU speed did not seem to play any part in the equation, the slowest machine ran the sample pretty well and the fastest almost came to halt. What did matter however was the graphics card. All machines had different cards. All machines are Dell computers. Not that the brand is the probable bad guy, but might be worth noticing.

Working:
ATI Radeon x600
ATI Radeon Mobility x600
ATI something 128 32 Mb
2xNVidia Geforce 6800 Ultra (Dual card configuration) (Although pretty slow, this machine has the most powerful CPU)

Non-working:
NVidia Geforce 7600
NVidia Geforce 7800 GTX
NVidia Geforce 6800 Standard (Single card)
NVidia Geforce 4 Ti 4600

I have tried other treeview controls with checkboxes enabled in the same manner in which I noticed no slowdowns whatsoever.

Well, I'm pretty much stuck here, hope you can come up with some clues. The only obvious similarity is that apart from the dual NVidia card, ATI works almost flawless and NVidia works pretty lousy.

Thanks for your help!
Jakob

[Infralution]

0.5 seconds for a repaint is definitely much worse then you should be seeing. You aren't running this from within the debugger are you? The VS2005 debugger can have quite an adverse affect on performance depending on your debug settings.

My laptop is a Dell 8600 with an NVidia GeForce FX Go5200 - shows no problems. We also have a Dell 5150 which has no issues. We haven't had any other reports from customers of this issue. I suspect you may be correct and it may be a graphics card issue. We will try to get hold of one of the cards you have listed and see if we can replicate the issue.

The problem may be related to mechanism used to clip the visible editor controls in the scrollable area of the control. If you set the column containing the checkboxes to be pinned does the issue disappear?
_________________
Infralution Support

[Infralution]

I've now found some more machines with various Nvidia adaptors - but still haven't seen the problem. The video cards tested include:

Nvidia GeForce 6600 LE
Nvidia GeForce 4 Ti 4200
Nvidia GeForce FX 5200

I am ordering a NVidia Geforce 7600 GS to test the issue on exactly the same card as you. Theoretically this is better card then all of the above and so shouldn't have a performance problem.
_________________
Infralution Support

[Infralution]

We've now purchased and installed an NVidia GeForce 7600GS and installed it on a Dell Dimension 5150. There is no problem evident - in fact the performance is blistering.

We now have a nice new graphics card in our test machine - but still no clue what could be causing your issue. You aren't running under some sort of virtual machine (such as VMWare) are you?
_________________
Infralution Support

[Guest]

What version of drivers are you using? We'll try grab the same versions if possible.

[Infralution]

The driver version is 8.3.9.1 dated 9/02/2006

Did you try setting the column containing the checkboxes to be pinned and seeing whether the issue was still evident?
_________________
Infralution Support