Cursor Perfromance

history · Post by **history** » Tue Mar 18, 2008 5:15 pm

Is there any work being done on enhancing the performance of the cursors. We had some discussions a few months ago on cursor performance and how the fast cursor has a number of paint issues while the regular cursor is choppy in movement when there are a large number of points due to the painting.

Narcís · Post by **Narcís** » Wed Mar 19, 2008 11:46 am

Hi history,

No, there is no work being done at the moment. Could you please send us a sample project that we can run "as-is" here to highlight the problems you are experiencing with fastcursor?

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

Thanks in advance.

history · Post by **history** » Wed Mar 19, 2008 12:29 pm

I will take a look for the sample code.

One of the main concerns is that because you don't repaint using the fastcursor then information on the cursor cannot be displayed within the rectangletool as the cursor moves across the screen. The other issue is that if you move the cursor quickly accross the screen there are times when you will see ghosts of the cursor displayed, not sure if that has been corrected as we had to drop the fast cursor and use the cursor for those reasons.

I had an email discussion with Christopher a number of months ago on this and I believe the last response was that Steema would look at the cursor. Just checking to see if there was any work done on it so I could revisit the fastcursor again. Not sure that I still have the email chain.

Our application can be used to displays large amounts of data and cursor performance is one of the concerns we have upon customer release.

Narcís · Post by **Narcís** » Thu Apr 24, 2008 2:57 pm

Hi history,

You may be intrested in checking out the new TeeChart for .NET v2 update build that fixes this issue. The fix has also been implemented for the next TeeChart for .NET v3 maintenance release due to be out on early May.

history · Post by **history** » Thu Apr 24, 2008 5:25 pm

I did a quick check and am able to display another vertical line on the chart when using fastcursor; have the cursor track the mouse and click the right mouse button.

One of the issues with fastcursor is that you may want to display information on the chart as the cursor is changing. With TeeChart you seem to be only able to paint all the screen and not a portion of the screen.

Samples:
Can I have a rectangular tool on the screen and display cursor info in the rectangular tool as the cursor moves across the screen. Here I would want to repaint the only the rectangular tool text.

The cursor is sometimes difficult to see when it overlays on top of the left or right axis. We paint a small rectangle on top of the cursor that is moved along the top axis when the cursor moves. This requires some after draw functionality as the cursor changes. Ideally you would want to only redraw a small portion of the top axis not the whole chart.

Narcís · Post by **Narcís** » Fri Apr 25, 2008 8:18 am

Hi history,

As I posted in my previous message, this bug fix has not been published in TeeChart for .NET v3 yet.

Using the fixed v3 sources I can use the example at All Features\Welcome !\Chart styles\Standard\Line(Strip)\Interpolating line series with the cursor tool set to FastCursor=true and without this problem.

Could you please wait for next v3 maintenance release and check those issues again with that version?

Thanks in advance.

history · Post by **history** » Fri Apr 25, 2008 12:16 pm

I used your version 2 build to test

Narcís · Post by **Narcís** » Mon Apr 28, 2008 10:12 am

Hi history,

Thanks for the information. I couldn't reproduce the cursor issue here. Could you please send us a simple example project we can run "as-is" to reproduce the problem here?

Regarding only painting an area in the chart, it is not directly supported by TeeChart but you can use .NET Framework's ControlPaint class in the AfterDraw event. You can find a ControlPaint example here.