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Limit on number of data points in TWaterfallSeries?

Posted: Tue Nov 02, 2004 8:26 pm
by 5893322
I'm using v 5.02 of the TeeChart libraries and TChart in particular. I've realized that TChart, used in its 3D waterfall context, seems to have a problem with adding series ( TWaterFallSeries in this case ) to the chart that have over 2001 values. I can add TWaterFallSeries objects to the chart that have from 1 to 2001 values just fine... but when I try to add one with 2002 values... Boom!!! Access Violation in TWinControl.PaintHandler. I'm using the "AddXYZ" method to add the values to the series. It seems unrealistic that the TWaterfallSeries would have such a small limit of values but I can't see what else could be going on here? Is this a bug that has been remedied in the TeeChart libraries after v5.02? Am I missing some property or something?

Posted: Wed Nov 03, 2004 6:55 am
by Marjan
Hi, Steve.

Some 3D series have a limitation on number of points in z (some also in x) direction. For example, in the latest Teechart version the number of surface series points in x,z direction is limited to 3000 points. This is controlled by private constant in the TeeSurfa.pas unit, namely :

Code: Select all

  Const MaxAllowedCells=3000; { max 3000 x 3000 cells }
In Teechart v5 MaxAllowedCells is set to 2000 meaning surface series can have only 2000 points in x or z direction (maximum grid size 2000x2000). As Waterfall series is derived from surface series, the same limitations apply for this series type meaning you can have only 2000 points in x direction and 2000 points in z direction.
If you have TeeChart source code you can increase this value by changing the MaxAllowedCells constant and recompiling TeeChart sources. But you must be aware that increasing 2d array size will eat a lot of memory and drastically slow down the drawing time. If you have a lot of points you want to display then perhaps it's a better solution to reduce the number of points before you pass them to series. I think there are couple of discussions about reducing the number of points available in this forum and also at articles section.

Posted: Thu Nov 04, 2004 12:54 am
by 5893322
Thanks for confirming that for me Marjan. I appreciate it immensely.