ChartDirector 6.0 (ASP/COM/VB Edition)

Continuous Contour Coloring




This example demonstrates continuous coloring of the ContourLayer.

By default, a contour layer will be discretely colored, which means the color will change in discrete steps according to the z level. In continuous coloring, the color will change continuously according to the z level. Continuous coloring can be enabled using ColorAxis.setColorGradient or ColorAxis.setColorScale.

Source Code Listing

[Web Version (in ASP)] aspdemo\smoothcontour.asp
<%@ language="vbscript" %>
<%
Set cd = CreateObject("ChartDirector.API")

' The x and y coordinates of the grid
dataX = Array(-10, -9, -8, -7, -6, -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
dataY = Array(-10, -9, -8, -7, -6, -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10)

' The values at the grid points. In this example, we will compute the values using the formula z =
' Sin(x / 2) * Sin(y / 2).
ReDim dataZ((UBound(dataX) + 1) * (UBound(dataY) + 1) - 1)
For yIndex = 0 To UBound(dataY)
    y = dataY(yIndex)
    For xIndex = 0 To UBound(dataX)
        x = dataX(xIndex)
        dataZ(yIndex * (UBound(dataX) + 1) + xIndex) = Sin(x / 2.0) * Sin(y / 2.0)
    Next
Next

' Create a XYChart object of size 600 x 500 pixels
Set c = cd.XYChart(600, 500)

' Add a title to the chart using 18 points Times New Roman Bold Italic font
Call c.addTitle("Nano Lattice Twister Field Intensity        ", "timesbi.ttf", 18)

' Set the plotarea at (75, 40) and of size 400 x 400 pixels. Use semi-transparent black (80000000)
' dotted lines for both horizontal and vertical grid lines
Call c.setPlotArea(75, 40, 400, 400, -1, -1, -1, c.dashLineColor(&H80000000, cd.DotLine), -1)

' Set x-axis and y-axis title using 12 points Arial Bold Italic font
Call c.xAxis().setTitle("Lattice X Direction (nm)", "arialbi.ttf", 12)
Call c.yAxis().setTitle("Lattice Y Direction (nm)", "arialbi.ttf", 12)

' Set x-axis and y-axis labels to use Arial Bold font
Call c.xAxis().setLabelStyle("arialbd.ttf")
Call c.yAxis().setLabelStyle("arialbd.ttf")

' When auto-scaling, use tick spacing of 40 pixels as a guideline
Call c.yAxis().setTickDensity(40)
Call c.xAxis().setTickDensity(40)

' Add a contour layer using the given data
Set layer = c.addContourLayer(dataX, dataY, dataZ)

' Set the contour color to transparent
Call layer.setContourColor(cd.Transparent)

' Move the grid lines in front of the contour layer
Call c.getPlotArea().moveGridBefore(layer)

' Add a color axis (the legend) in which the left center point is anchored at (495, 240). Set the
' length to 370 pixels and the labels on the right side.
Set cAxis = layer.setColorAxis(495, 240, cd.Left, 370, cd.Right)

' Add a bounding box to the color axis using light grey (eeeeee) as the background and dark grey
' (444444) as the border.
Call cAxis.setBoundingBox(&Heeeeee, &H444444)

' Add a title to the color axis using 12 points Arial Bold Italic font
Call cAxis.setTitle("Twist Pressure (Twist-Volt)", "arialbi.ttf", 12)

' Set color axis labels to use Arial Bold font
Call cAxis.setLabelStyle("arialbd.ttf")

' Use smooth gradient coloring
Call cAxis.setColorGradient(True)

' Output the chart
Response.ContentType = "image/jpeg"
Response.BinaryWrite c.makeChart2(cd.JPG)
Response.End
%>

[Windows Version (in Visual Basic)] vbdemo\smoothcontour.cls
Public Sub createChart(viewer As Object, chartIndex As Integer)

    Dim cd As New ChartDirector.API

    ' The x and y coordinates of the grid
    Dim dataX()
    dataX = Array(-10, -9, -8, -7, -6, -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
    Dim dataY()
    dataY = Array(-10, -9, -8, -7, -6, -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10)

    ' The values at the grid points. In this example, we will compute the values using the formula z
    ' = Sin(x / 2) * Sin(y / 2).
    ReDim dataZ((UBound(dataX) + 1) * (UBound(dataY) + 1) - 1)
    Dim yIndex As Long
    For yIndex = 0 To UBound(dataY)
        Dim y As Double
        y = dataY(yIndex)
        Dim xIndex As Long
        For xIndex = 0 To UBound(dataX)
            Dim x As Double
            x = dataX(xIndex)
            dataZ(yIndex * (UBound(dataX) + 1) + xIndex) = Sin(x / 2.0) * Sin(y / 2.0)
        Next
    Next

    ' Create a XYChart object of size 600 x 500 pixels
    Dim c As XYChart
    Set c = cd.XYChart(600, 500)

    ' Add a title to the chart using 18 points Times New Roman Bold Italic font
    Call c.addTitle("Nano Lattice Twister Field Intensity        ", "timesbi.ttf", 18)

    ' Set the plotarea at (75, 40) and of size 400 x 400 pixels. Use semi-transparent black
    ' (80000000) dotted lines for both horizontal and vertical grid lines
    Call c.setPlotArea(75, 40, 400, 400, -1, -1, -1, c.dashLineColor(&H80000000, cd.DotLine), -1)

    ' Set x-axis and y-axis title using 12 points Arial Bold Italic font
    Call c.xAxis().setTitle("Lattice X Direction (nm)", "arialbi.ttf", 12)
    Call c.yAxis().setTitle("Lattice Y Direction (nm)", "arialbi.ttf", 12)

    ' Set x-axis and y-axis labels to use Arial Bold font
    Call c.xAxis().setLabelStyle("arialbd.ttf")
    Call c.yAxis().setLabelStyle("arialbd.ttf")

    ' When auto-scaling, use tick spacing of 40 pixels as a guideline
    Call c.yAxis().setTickDensity(40)
    Call c.xAxis().setTickDensity(40)

    ' Add a contour layer using the given data
    Dim layer As ContourLayer
    Set layer = c.addContourLayer(dataX, dataY, dataZ)

    ' Set the contour color to transparent
    Call layer.setContourColor(cd.Transparent)

    ' Move the grid lines in front of the contour layer
    Call c.getPlotArea().moveGridBefore(layer)

    ' Add a color axis (the legend) in which the left center point is anchored at (495, 240). Set
    ' the length to 370 pixels and the labels on the right side.
    Dim cAxis As ColorAxis
    Set cAxis = layer.setColorAxis(495, 240, cd.Left, 370, cd.Right)

    ' Add a bounding box to the color axis using light grey (eeeeee) as the background and dark grey
    ' (444444) as the border.
    Call cAxis.setBoundingBox(&Heeeeee, &H444444)

    ' Add a title to the color axis using 12 points Arial Bold Italic font
    Call cAxis.setTitle("Twist Pressure (Twist-Volt)", "arialbi.ttf", 12)

    ' Set color axis labels to use Arial Bold font
    Call cAxis.setLabelStyle("arialbd.ttf")

    ' Use smooth gradient coloring
    Call cAxis.setColorGradient(True)

    ' Output the chart
    Set viewer.Picture = c.makePicture()

End Sub