chart autorepaint or series autorepaint

[David]

As suggested by many posts, it is better to set autorepaint false to speed up plotting great number of data, but when I search the help file, both chart and series have autorepaint property. So which one should I set or should I set both.

And how to disable locking for single thread using C++?

[Yeray]

Hi David,

FastLineSeries' autorepaint property prevents the whole chart to be repainted every time the series is updated or a vale is added to it.
Chart's autorepaint property prevents the chart to be repainted at all.

Regarding the threading, here is an explanation about TeeChart limitations.

[David]

My question was not answered yet. I know there is autorepaint property for both fastline and chart. My question is which one I should use or should I set both? As in the following code, are the two for loops able to make the plotting even faster? With the chart autorepaint disabled, does it matter to disable/enable series autorepaint?

Code: Select all

m_chart1.SetAutoRepaint(FALSE);
for(int i=0;i<3;i++)
     m_chart1.Series(i).GetAsFastLine().SetAutoRepaint(FALSE);

//code to update series(0) to series(3)

for(int i=0;i<3;i++)
     m_chart1.Series(i).GetAsFastLine().SetAutoRepaint(TRUE);

m_chart1.SetAutoRepaint(TRUE);
m_chart1.Repaint();

As for disable locking, in the real-time chart article, it is Basic code as

Code: Select all

  // When using only a single thread, disable locking:
  Chart1.Canvas.ReferenceCanvas.Pen.OwnerCriticalSection := nil;
  Series1.LinePen.OwnerCriticalSection := nil;

So my another question is how to realize it in C++?

[Yeray]

Hi David,

I recommend you to use series' autorepaint instead of chart's autorepaint. Then, if you need even more optimization, you could try chart's autorepaint instead of series' autorepaint but series drawing is the process that takes more time (incremented with the number of points to show). But, as you suspected, setting chart's autorepaint to false, series' autorepaint to false will be redundant.

Regarding the real-time article, I'm afraid it's not possible to lock TeeChart's pen in ActiveX.

[David]

I am a little bit confused. If series drawing is the process that takes more time, it seems logic to use series' autopaint, but then you said to get more optimization, I should use chart's autopaint. So exactly which way is faster, using series' autopaint or using chart's autopaint?

[Yeray]

Hi David,

Series autorepaint to false forces the series to not be redrawn.
Chart autorepaint to false forces the series to not be redrawn but also axes, titles,...

[David]

OK, got it. Thank goodness it is solved before 2010. Happy new year to you!

[Yeray]

Hi David,

The same to you!