ChartDirector for C++ 7.2 Release Notes
ChartDirector for C++ 7.2 is a bug fixing release. It fixes bugs discovered since
ChartDirector for C++ 7.1.
Bugs Fixed
- Moving correlation does not handle Chart::NoValue points correctly
ArrayMath::movCorr computes moving coorelation incorrectly if there are Chart::NoValue points.
This issue in now fixed.
- MFC CChartViewer control resource leak
The MFC CChartViewer control accepts a chart object as input and generates a Windows bitmap
object for displaying on screen. If the control is deleted without clearing the bitmap (by
setting the chart to null), there will be resource leak. CChartViewer will now automatically
clear the bitmap if necessary when the control is about the be destroyed (in the MFC OnDestroy
handler).
This issue affects applications that delete controls with program
code. It does not affect applications that add controls to a form at design time and never
delete the controls.
- PNG compression optimization
The image compression parameters for PNG has been optimized. On average, PNG files generated
by ChartDirector should have smaller file size.
- Discrete Heat Map extra fields incorrect if the x and y arrays are given as the grid line
coordinates of the cells.
If a discrete heat map is created by providing the x, y and z arrays, the x and y arrays
can be the center coordinates of the cells or the coordinates of the grid lines between cells.
ChartDirector can distinguish the two cases by considering the size of the 3 arrays.
However, when adding custom labels to the cells with extra fields,
ChartDirector always assumes the x and y arrays are the center coordinates of the cells. The
label position will be incorrect if the x and y arrays are in fact the grid line coordinates.
This issue is now fixed.
- Lowess curve fitting may not fit optimally at the end points of the curve
For data with large number of points, if lowess curve fitting is used with a small smoothing factor,
the curve may not fit optimally at the end points of the curve. This can be hard to notice because
the end points are only a very small part of the curve consisting of large number of points. However,
it may become noticible if the chart is highly zoomed in at an end point.
- Multi-bar chart data label position incorrect if it uses multiple y-axes.
For a multi-bar chart (including multi-stacked bar chart), ChartDirector uses the same y-axis scale
to calculate the positions of the data labels for all bars. This is incorrect if some data sets use
different y-axes. This issue is now fixed.
Behaviour Changes
- No behaviour change is expected. Existing code should continue to work unmodified.
