public Chart GetChart(Chart chart)
{
if (String.IsNullOrEmpty(chart.Expression))
{
return chart;
}
if (!chart.Expression.ToLower().Contains('x'))
{
return chart;
}
if (chart.MaxX - chart.MinX <= 0)
{
return chart;
}
if (chart.MaxY - chart.MinY <= 0)
{
return chart;
}
if (chart.Width <= 0 || chart.Height <= 0)
{
return chart;
}
Func<Double, Double> expressionEvaluator = this.CreateExpressionEvaluator(chart.Expression.Replace(",", "."));
if (expressionEvaluator == null)
{
return chart;
}
OperationContext operationContext = OperationContext.Current;
Thread thread = new Thread(new ThreadStart(delegate
{
using (new OperationContextScope(operationContext))
{
ChartPlotter chartProtter = new ChartPlotter();
chartProtter.Width = chart.Width;
chartProtter.Height = chart.Height;
List<EnumerableDataSource<Double>> pointDataSources = this.CreatePointDataSources(chart, expressionEvaluator);
foreach (EnumerableDataSource<Double> pointDataSource in pointDataSources)
{
LineGraph lineGraph = new LineGraph(pointDataSource);
lineGraph.LinePen = new System.Windows.Media.Pen(lineGraph.LinePen.Brush, 2.0);
chartProtter.Children.Add(lineGraph);
}
chartProtter.LegendVisible = false;
using (MemoryStream memoryStream = new MemoryStream())
{
chartProtter.SaveScreenshotToStream(memoryStream, "png");
chart.ImageBytes = memoryStream.ToArray();
}
}
}));
thread.SetApartmentState(System.Threading.ApartmentState.STA);
thread.Start();
thread.Join();
return chart;
}
private List<EnumerableDataSource<Double>> CreatePointDataSources(Chart chart, Func<Double, Double> expressionEvaluator)
{
Double coefficient = (chart.MaxX - chart.MinX) / POINTS_COUNT;
IEnumerable<Double> data = Enumerable.Range(0, POINTS_COUNT).Select(i => chart.MinX + (Double)i * coefficient);
List<List<Double>> dataRanges = this.SplitData(data, expressionEvaluator, chart.MinY, chart.MaxY);
List<EnumerableDataSource<Double>> pointDataSources = new List<EnumerableDataSource<Double>>();
foreach (List<Double> dataRange in dataRanges)
{
EnumerableDataSource<Double> pointDataSource = new EnumerableDataSource<Double>(dataRange);
pointDataSource.SetXMapping(i => i);
pointDataSource.SetYMapping(expressionEvaluator);
pointDataSources.Add(pointDataSource);
}
return pointDataSources;
}
