CalculateZeroLine() Method

Calculates the Zero-line data value for the floor or ground plane of the Chart.

Syntax

Visual Basic

'Declaration
 
Protected Overloads Overridable Function CalculateZeroLine() As Double

C#

protected virtual double CalculateZeroLine()

Return Value

The real world data value subclasses should map to screen coordinates representing the Chart's floor or ground plane.

Remarks

Function calculating the data value corresponding to the proverbial floor (or ground X-Y plane in 3-D charts) of the chart. Developers' ChartLayer subclasses should then map this to a corresponding pixel-value on whatever axis is appropriate to their chart type using that IAdvanceAxis' Map function. An accurate zero-line prevents chart elements from floating above/below the floor or ground plane.

Calculation of the zero line is with regard to:

Data value 0.0, if zero lies in data within the range of data.

The maximum data value, if all data is less than zero (negative or -ve).

The minimum data value, if all data is greater than zero (positive or +ve).

Requirements

Target Platforms: Windows 10, Windows 8.1, Windows 8, Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2