ChartDirector 7.0 (Java 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

[JSP Version] jspdemo/smoothcontour.jsp
<%@page import="ChartDirector.*, java.util.*" %> <% // The x and y coordinates of the grid double[] dataX = {-10, -9, -8, -7, -6, -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}; double[] dataY = {-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). double[] dataZ = new double[dataX.length * dataY.length]; for(int yIndex = 0; yIndex < dataY.length; ++yIndex) { double y = dataY[yIndex]; for(int xIndex = 0; xIndex < dataX.length; ++xIndex) { double x = dataX[xIndex]; dataZ[yIndex * dataX.length + xIndex] = Math.sin(x / 2.0) * Math.sin(y / 2.0); } } // Create a XYChart object of size 600 x 500 pixels XYChart c = new XYChart(600, 500); // Add a title to the chart using 18 points Times New Roman Bold Italic font c.addTitle("Nano Lattice Twister Field Intensity ", "Times New Roman Bold Italic", 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 c.setPlotArea(75, 40, 400, 400, -1, -1, -1, c.dashLineColor(0x80000000, Chart.DotLine), -1); // Set x-axis and y-axis title using 12 points Arial Bold Italic font c.xAxis().setTitle("Lattice X Direction (nm)", "Arial Bold Italic", 12); c.yAxis().setTitle("Lattice Y Direction (nm)", "Arial Bold Italic", 12); // Set x-axis and y-axis labels to use Arial Bold font c.xAxis().setLabelStyle("Arial Bold"); c.yAxis().setLabelStyle("Arial Bold"); // When auto-scaling, use tick spacing of 40 pixels as a guideline c.yAxis().setTickDensity(40); c.xAxis().setTickDensity(40); // Add a contour layer using the given data ContourLayer layer = c.addContourLayer(dataX, dataY, dataZ); // Set the contour color to transparent layer.setContourColor(Chart.Transparent); // Move the grid lines in front of the contour layer 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. ColorAxis cAxis = layer.setColorAxis(495, 240, Chart.Left, 370, Chart.Right); // Add a bounding box to the color axis using light grey (eeeeee) as the background and dark grey // (444444) as the border. cAxis.setBoundingBox(0xeeeeee, 0x444444); // Add a title to the color axis using 12 points Arial Bold Italic font cAxis.setTitle("Twist Pressure (Twist-Volt)", "Arial Bold Italic", 12); // Set color axis labels to use Arial Bold font cAxis.setLabelStyle("Arial Bold"); // Use smooth gradient coloring cAxis.setColorGradient(true); // Output the chart WebChartViewer viewer = new WebChartViewer(request, "chart1"); viewer.setChart(c, Chart.SVG); // Include tool tip for the chart viewer.setImageMap(c.getHTMLImageMap("", "", "title='<*cdml*>X: {x|2}<*br*>Y: {y|2}<*br*>Z: {z|2}'") ); // Output Javascript chart model to support contour chart tooltips viewer.setChartModel(c.getJsChartModel()); %> <!DOCTYPE html> <html> <head> <title>Continuous Contour Coloring</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;"> Continuous Contour Coloring </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 is the chart image ****** --> <%= viewer.renderHTML(response) %> </body> </html>