public void AddFunction(Function f)
{
_currentFunctions.Add(f);
}
// draw a single function
private void DrawFunction(Graphics g, Function f)
{
// a list of list of points is required to properly skip imaginary number(e.g sqrt(-1))
var pointsList = new List<List<PointF>> {new List<PointF>()};
bool lastNan = false;
for (float x = -Graph.NumOfCells/2; x < Graph.NumOfCells/2; x += Graph.Step)
// from -X border to X border og the graph
{
float y = f.Apply(x); // the y value of x is calculated thanks to reflection
PointF point = TransformPoint(new PointF(x, y));
// then the point obtained is converted to "real" coordinates
//when an imaginary number is discovered it creates a new separated list of points to draw
//every list of points will be drawn singularly
if (double.IsNaN(y))
{
if (!lastNan) // it creates a new list of points only if the last number wasn't imaginary
{
pointsList.Add(new List<PointF>());
lastNan = true;
}
}
// if a point exceeds the borders of the graph his Y components is set to not visible, to prevent overflow.
else if (point.Y > Graph.Heigth)
{
pointsList[pointsList.Count - 1].Add(new PointF(point.X, Graph.Heigth + FunctionPen.Width));
}
else if (point.Y < 0)
{
pointsList[pointsList.Count - 1].Add(new PointF(point.X, -FunctionPen.Width));
}
else
{
lastNan = false;
pointsList[pointsList.Count - 1].Add(point); //
}
}
//draws each list of points only if the list has a number of elements > 1
foreach (var list in pointsList.Where(list => list.Count > 1))
{
g.DrawLines(FunctionPen, list.ToArray());
}
}