Steema Central

Hello,
I have a chart (V8.02 VCL) with a horizontal line that the user can move up and down. I use the position to do some computations. The chart is 2D only.

The first approach was the colorline tool, which worked properly so far but drives the CPU usage to a very high level when moving. The PC becomes so slow that this solution is actually unusable.

The second approach was Cursor Tool.
It is much faster than Colorline, but is lacking the OnBeginDragLine and OnEndDragLine Events.

Im looking for a solution that combines the features of the Colorlinetool and the Cursortool.

Any Idea ?

Hello Gerhard,

The first approach was the colorline tool, which worked properly so far but drives the CPU usage to a very high level when moving. The PC becomes so slow that this solution is actually unusable.

We are interested on reproducing this issue here and trying to find a solution to it. Could you please send us a simple example project we can run "as-is" to reproduce the problem here?

You can either post your files at news://www.steema.net/steema.public.attachments newsgroup or at our upload page.

Thanks in advance.

Hello Narcis,

I tried to send you an example project, but it did not work.
Calling the upload page always gives the error "Server Error in '/' Application".

Clicking on the "news://www.steema.net/steema.public.attachments" link opens Outlook Express which I never used on this PC. Outllok Express is unable to connect to the server although it has the same settings as the Internet explorer which works.

I will send the project to info@steema.com.

Best Regards
Gerhard Sachs

Hi Gerhard,

Thanks for the example project.

We are still unable to reproduce the ColorLine issue here. Could you please try using TeeChart Pro v8.04 VCL which was published recently?

If this doesn't help please give us some details about the machine where you are running the application. Can you reproduce this in other machines?

Regarding the CursorTool issue, it can be solved calling Chart1.Draw; after assigning XValue and YValue.

Hope this helps!

Hello Narcis,

the example was tested on 2 different PC's, both are Dell desktop PC's with rather different components.
Both run Windows XP Pro, one with SP2, the other with SP3.
I have sent the example as executable too to allow you to see exactly the same behaviour that I see here.

I will test the example on other PC's too and will report the CPU load.
Then I will try if V8.04 is changing anything.
I'm notifying you as sonn as possible.

Regards
Gerhard Sachs

Hello Narcis,

I have now tested the Colorlinetest on different office PC's, one Lenovo and three Dell. Most of them have a Intel Core 2 Duo CPU with one or 2GB Ram. They have different graphic boards from Matrox, NVidia or ATI.
All show the same effect that CPU usage increases heavily when fast dragging the colorline (about 5-8 times / s). CPU usage for the Core2Duo CPU's goes from a few percent to about 25...50%.
When I run a small tool named CPUUse and tell it to run the CPU at 100%, the task manager shows both bars at 50%. so the percentages must be doubled to give the real CPU usage.
I installed TeeChart 8.04 and recompiled the software.
There is no difference in CPU usage to V8.02 which the demo was compiled with.
The cursortoll is now working as expected aften I added the chart1.draw , thank you for the help.

Regards
Gerhard Sachs

Hi Gerhard,

Thanks for the information. I've finally been able to clearly reproduce this in a single CPU machine. Duo/Quad CPUs its usage increased to 20-25%. I've added this (TV52013501) to the bug list to be investigated for next releases.