ChartDirector 7.0 (ASP/COM/VB Edition)

Round Meters with Readout


  

This example demonstrates round meters configured with a large pointer cap to display the meter value.

The pointer cap is the circular object at the center of the meter. In this example, using AngularMeter.setCap2, the pointer cap is set to an exceptionally large size so that it can act as a place to display text. The text is added using BaseChart.addText, centered at the meter center.

In one of the meters, the pointer is configured to be floating, which means the base of the pointer is not fixed at the meter center. The pointer looks like a triangle somewhere between the center and the perimeter, pointing to the meter value. This pointer is added using AngularMeter.addPointer2 with TriangularPointer2 just like a standard pointer, but with additional arguments to specify the radial position of the pointer base and tip, as well as the pointer width.

Source Code Listing

[Web Version (in ASP)] aspdemo\roundmeterreadout.asp
<%@ language="vbscript" %> <% Set cd = CreateObject("ChartDirector.API") ' This script can draw different charts depending on the chartIndex Sub createChart(viewer, chartIndex) ' The value to display on the meter value = 54 ' The main color of the four meters in this example. The other colors and gradients are derived ' from the main color. colorList = Array(&H0033dd, &Haaaa00) mainColor = colorList(chartIndex) ' ' In this example, we demonstrate how to parameterized by size, so that the chart size can be ' changed by changing just one variable. ' size = 300 ' The radius of the entire meter, which is size / 2, minus 2 pixels for margin outerRadius = Int(size / 2 - 2) ' The radius of the meter scale scaleRadius = Int(outerRadius * 92 / 100) ' The radius of the color scale colorScaleRadius = Int(scaleRadius * 43 / 100) ' The width of the color scale colorScaleWidth = Int(scaleRadius * 10 / 100) ' Major tick length tickLength = Int(scaleRadius * 10 / 100) ' Major tick width tickWidth = Int(scaleRadius * 1 / 100 + 1) ' Label font size fontSize = Int(scaleRadius * 13 / 100) ' Radius of readout circle as a ratio to the scale radius readOutRadiusRatio = 0.333333333333 ' Readout font size readOutFontSize = Int(scaleRadius * 24 / 100) ' ' Create an angular meter based on the above parameters ' ' Create an AngularMeter object of the specified size. In this demo, we use black (0x000000) as ' the background color. You can also use transparent or other colors. Set m = cd.AngularMeter(size, size, &H000000) ' Set the default text and line colors to white (0xffffff) Call m.setColor(cd.TextColor, &Hffffff) Call m.setColor(cd.LineColor, &Hffffff) ' Set meter center and scale radius, and set the scale angle from -180 to +90 degrees Call m.setMeter(size / 2, size / 2, scaleRadius, -180, 90) ' Background gradient with the mainColor at the center and become darker near the border bgGradient = Array(0, mainColor, 0.5, m.adjustBrightness(mainColor, 0.75), 1, _ m.adjustBrightness(mainColor, 0.15)) ' Fill the meter background with the background gradient Call m.addRing(0, outerRadius, m.relativeRadialGradient(bgGradient, outerRadius * 0.66)) ' Gradient for the neon backlight, with the main color at the scale radius fading to transparent neonGradient = Array(0.89, cd.Transparent, 1, mainColor, 1.07, cd.Transparent) Call m.addRing(Int(scaleRadius * 85 / 100), outerRadius, m.relativeRadialGradient(neonGradient)) ' The neon ring at the scale radius with width equal to 1/80 of the scale radius, creating using ' a brighter version of the main color Call m.addRing(scaleRadius, Int(scaleRadius + scaleRadius / 80), m.adjustBrightness(mainColor, _ 2)) ' Meter scale is 0 - 100, with major/minor/micro ticks every 10/5/1 units Call m.setScale(0, 100, 10, 5, 1) ' Set the scale label style, tick length and tick width. The minor and micro tick lengths are ' 80% and 60% of the major tick length, and their widths are around half of the major tick ' width. Call m.setLabelStyle("Arial Italic", fontSize) Call m.setTickLength(-tickLength, -Int(tickLength * 80 / 100), -Int(tickLength * 60 / 100)) Call m.setLineWidth(0, tickWidth, Int((tickWidth + 1) / 2), Int((tickWidth + 1) / 2)) ' Demostrate different types of color scales and putting them at different positions. smoothColorScale = Array(0, &H0000ff, 25, &H0088ff, 50, &H00ff00, 75, &Hdddd00, 100, &Hff0000) highColorScale = Array(70, cd.Transparent, 100, &Hff0000) If chartIndex = 0 Then ' Add the smooth color scale Call m.addColorScale(smoothColorScale, colorScaleRadius, colorScaleWidth) ' Add a red (0xff0000) pointer Call m.addPointer2(value, &Hff0000) Else ' Add the high color scale at the default position Call m.addColorScale(highColorScale) ' Add a red (0xff0000) triangular pointer starting from 40% and ending at 60% of scale ' radius, with a width 6 times the default Call m.addPointer2(value, &Hff0000, -1, cd.TriangularPointer2, 0.4, 0.6, 6) End If ' Configure a large "pointer cap" to be used as the readout circle at the center. The cap border ' width is set to 1.5% of the scale radius. The cap color is darker version of the main color. ' The border color is a brighter version of the main color with 75% brightness gradient effect. Call m.setCap2(cd.Transparent, m.adjustBrightness(mainColor, 0.3), m.adjustBrightness( _ mainColor, 1.5), 0.75, 0, readOutRadiusRatio, 0.015) ' Add value label at the center using a brighter version of the main color and Arial Italic font Call m.addText(size / 2, size / 2, m.formatValue(value, "{value|0}"), "Arial Italic", _ readOutFontSize, m.adjustBrightness(mainColor, 2.5), cd.Center).setMargin(0) ' Add glare up to the scale radius Call m.addGlare(scaleRadius) ' Output the chart Call viewer.setChart(m, cd.SVG) End Sub ' This example includes 2 charts Dim viewers(1) For i = 0 To Ubound(viewers) Set viewers(i) = cd.WebChartViewer(Request, "chart" & i) Call createChart(viewers(i), i) Next %> <!DOCTYPE html> <html> <head> <title>Round Meters with Readout</title> <!-- Include ChartDirector Javascript Library to support chart interactions --> <script type="text/javascript" src="cdjcv.js"></script> </head> <body style="margin:5px 0px 0px 5px"> <div style="font:bold 18pt verdana;"> Round Meters with Readout </div> <hr style="border:solid 1px #000080; background:#000080" /> <div style="font:10pt verdana; margin-bottom:1.5em"> <a href="viewsource.asp?file=<%= Request("SCRIPT_NAME") %>">View Chart Source Code</a> </div> <!-- ****** Here are the chart images ****** --> <% For i = 0 To Ubound(viewers) Call Response.Write(viewers(i).renderHTML()) Call Response.Write(" ") Next %> </body> </html>

[Windows Version (in Visual Basic)] vbdemo\roundmeterreadout.cls
Public Sub createChart(viewer As Object, chartIndex As Integer) Dim cd As New ChartDirector.API ' The value to display on the meter Dim value As Double value = 54 ' The main color of the four meters in this example. The other colors and gradients are derived ' from the main color. Dim colorList() colorList = Array(&H0033dd, &Haaaa00) Dim mainColor As Long mainColor = colorList(chartIndex) ' ' In this example, we demonstrate how to parameterized by size, so that the chart size can be ' changed by changing just one variable. ' Dim size As Long size = 300 ' The radius of the entire meter, which is size / 2, minus 2 pixels for margin Dim outerRadius As Long outerRadius = Int(size / 2 - 2) ' The radius of the meter scale Dim scaleRadius As Long scaleRadius = Int(outerRadius * 92 / 100) ' The radius of the color scale Dim colorScaleRadius As Long colorScaleRadius = Int(scaleRadius * 43 / 100) ' The width of the color scale Dim colorScaleWidth As Long colorScaleWidth = Int(scaleRadius * 10 / 100) ' Major tick length Dim tickLength As Long tickLength = Int(scaleRadius * 10 / 100) ' Major tick width Dim tickWidth As Long tickWidth = Int(scaleRadius * 1 / 100 + 1) ' Label font size Dim fontSize As Long fontSize = Int(scaleRadius * 13 / 100) ' Radius of readout circle as a ratio to the scale radius Dim readOutRadiusRatio As Double readOutRadiusRatio = 0.333333333333 ' Readout font size Dim readOutFontSize As Long readOutFontSize = Int(scaleRadius * 24 / 100) ' ' Create an angular meter based on the above parameters ' ' Create an AngularMeter object of the specified size. In this demo, we use black (0x000000) as ' the background color. You can also use transparent or other colors. Dim m As AngularMeter Set m = cd.AngularMeter(size, size, &H000000) ' Set the default text and line colors to white (0xffffff) Call m.setColor(cd.TextColor, &Hffffff) Call m.setColor(cd.LineColor, &Hffffff) ' Set meter center and scale radius, and set the scale angle from -180 to +90 degrees Call m.setMeter(size / 2, size / 2, scaleRadius, -180, 90) ' Background gradient with the mainColor at the center and become darker near the border Dim bgGradient() bgGradient = Array(0, mainColor, 0.5, m.adjustBrightness(mainColor, 0.75), 1, _ m.adjustBrightness(mainColor, 0.15)) ' Fill the meter background with the background gradient Call m.addRing(0, outerRadius, m.relativeRadialGradient(bgGradient, outerRadius * 0.66)) ' Gradient for the neon backlight, with the main color at the scale radius fading to transparent Dim neonGradient() neonGradient = Array(0.89, cd.Transparent, 1, mainColor, 1.07, cd.Transparent) Call m.addRing(Int(scaleRadius * 85 / 100), outerRadius, m.relativeRadialGradient(neonGradient)) ' The neon ring at the scale radius with width equal to 1/80 of the scale radius, creating using ' a brighter version of the main color Call m.addRing(scaleRadius, Int(scaleRadius + scaleRadius / 80), m.adjustBrightness(mainColor, _ 2)) ' Meter scale is 0 - 100, with major/minor/micro ticks every 10/5/1 units Call m.setScale(0, 100, 10, 5, 1) ' Set the scale label style, tick length and tick width. The minor and micro tick lengths are ' 80% and 60% of the major tick length, and their widths are around half of the major tick ' width. Call m.setLabelStyle("ariali.ttf", fontSize) Call m.setTickLength(-tickLength, -Int(tickLength * 80 / 100), -Int(tickLength * 60 / 100)) Call m.setLineWidth(0, tickWidth, Int((tickWidth + 1) / 2), Int((tickWidth + 1) / 2)) ' Demostrate different types of color scales and putting them at different positions. Dim smoothColorScale() smoothColorScale = Array(0, &H0000ff, 25, &H0088ff, 50, &H00ff00, 75, &Hdddd00, 100, &Hff0000) Dim highColorScale() highColorScale = Array(70, cd.Transparent, 100, &Hff0000) If chartIndex = 0 Then ' Add the smooth color scale Call m.addColorScale(smoothColorScale, colorScaleRadius, colorScaleWidth) ' Add a red (0xff0000) pointer Call m.addPointer2(value, &Hff0000) Else ' Add the high color scale at the default position Call m.addColorScale(highColorScale) ' Add a red (0xff0000) triangular pointer starting from 40% and ending at 60% of scale ' radius, with a width 6 times the default Call m.addPointer2(value, &Hff0000, -1, cd.TriangularPointer2, 0.4, 0.6, 6) End If ' Configure a large "pointer cap" to be used as the readout circle at the center. The cap border ' width is set to 1.5% of the scale radius. The cap color is darker version of the main color. ' The border color is a brighter version of the main color with 75% brightness gradient effect. Call m.setCap2(cd.Transparent, m.adjustBrightness(mainColor, 0.3), m.adjustBrightness( _ mainColor, 1.5), 0.75, 0, readOutRadiusRatio, 0.015) ' Add value label at the center using a brighter version of the main color and Arial Italic font Call m.addText(size / 2, size / 2, m.formatValue(value, "{value|0}"), "ariali.ttf", _ readOutFontSize, m.adjustBrightness(mainColor, 2.5), cd.Center).setMargin(0) ' Add glare up to the scale radius Call m.addGlare(scaleRadius) ' Output the chart Set viewer.Picture = m.makePicture() End Sub