ChartDirector 7.0 (Java Edition)
Round Meters with Readout
Source Code Listing
<%@page import="ChartDirector.*, java.util.*" %>
<%!
// Function to create the demo charts
void createChart(WebChartViewer viewer, int chartIndex)
{
// The value to display on the meter
double value = 54;
// The main color of the four meters in this example. The other colors and gradients are derived
// from the main color.
int[] colorList = {0x0033dd, 0xaaaa00};
int 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.
//
int size = 300;
// The radius of the entire meter, which is size / 2, minus 2 pixels for margin
int outerRadius = size / 2 - 2;
// The radius of the meter scale
int scaleRadius = outerRadius * 92 / 100;
// The radius of the color scale
int colorScaleRadius = scaleRadius * 43 / 100;
// The width of the color scale
int colorScaleWidth = scaleRadius * 10 / 100;
// Major tick length
int tickLength = scaleRadius * 10 / 100;
// Major tick width
int tickWidth = scaleRadius * 1 / 100 + 1;
// Label font size
int fontSize = scaleRadius * 13 / 100;
// Radius of readout circle as a ratio to the scale radius
double readOutRadiusRatio = 0.333333333333;
// Readout font size
int readOutFontSize = 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.
AngularMeter m = new AngularMeter(size, size, 0x000000);
// Set the default text and line colors to white (0xffffff)
m.setColor(Chart.TextColor, 0xffffff);
m.setColor(Chart.LineColor, 0xffffff);
// Set meter center and scale radius, and set the scale angle from -180 to +90 degrees
m.setMeter(size / 2, size / 2, scaleRadius, -180, 90);
// Background gradient with the mainColor at the center and become darker near the border
double[] bgGradient = {0, mainColor, 0.5, m.adjustBrightness(mainColor, 0.75), 1,
m.adjustBrightness(mainColor, 0.15)};
// Fill the meter background with the background gradient
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
double[] neonGradient = {0.89, Chart.Transparent, 1, mainColor, 1.07, Chart.Transparent};
m.addRing(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
m.addRing(scaleRadius, scaleRadius + scaleRadius / 80, m.adjustBrightness(mainColor, 2));
// Meter scale is 0 - 100, with major/minor/micro ticks every 10/5/1 units
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.
m.setLabelStyle("Arial Italic", fontSize);
m.setTickLength(-tickLength, -(tickLength * 80 / 100), -(tickLength * 60 / 100));
m.setLineWidth(0, tickWidth, (tickWidth + 1) / 2, (tickWidth + 1) / 2);
// Demostrate different types of color scales and putting them at different positions.
double[] smoothColorScale = {0, 0x0000ff, 25, 0x0088ff, 50, 0x00ff00, 75, 0xdddd00, 100,
0xff0000};
double[] highColorScale = {70, Chart.Transparent, 100, 0xff0000};
if (chartIndex == 0) {
// Add the smooth color scale
m.addColorScale(smoothColorScale, colorScaleRadius, colorScaleWidth);
// Add a red (0xff0000) pointer
m.addPointer2(value, 0xff0000);
} else {
// Add the high color scale at the default position
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
m.addPointer2(value, 0xff0000, -1, Chart.TriangularPointer2, 0.4, 0.6, 6);
}
// 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.
m.setCap2(Chart.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
m.addText(size / 2, size / 2, m.formatValue(value, "{value|0}"), "Arial Italic",
readOutFontSize, m.adjustBrightness(mainColor, 2.5), Chart.Center).setMargin(0);
// Add glare up to the scale radius
m.addGlare(scaleRadius);
// Output the chart
viewer.setChart(m, Chart.SVG);
}
%>
<%
// This example includes 2 charts
WebChartViewer[] viewers = new WebChartViewer[2];
for (int i = 0; i < viewers.length; ++i) {
viewers[i] = new WebChartViewer(request, "chart" + i);
createChart(viewers[i], i);
}
%>
<!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.jsp?file=<%=request.getServletPath()%>">View Source Code</a>
</div>
<!-- ****** Here are the chart images ****** -->
<%
for (int i = 0; i < viewers.length; ++i) {
out.write(viewers[i].renderHTML(response));
out.write(" ");
}
%>
</body>
</html>