ChartDirector Ver 3.0 (Perl Edition)

Custom Scatter Labels




This example demonstrates adding custom labels to data points.

Source Code Listing

[File: perldemo/scatterlabels.pl] (The CGI version is available as "perldemo_cgi/scatterlabels.pl".)
#!/usr/bin/perl use perlchartdir; #The XY points for the scatter chart my $dataX = [150, 400, 300, 1500, 800]; my $dataY = [0.6, 8, 5.4, 2, 4]; #The labels for the points my $labels = ["Nano\n100", "SpeedTron\n200 Lite", "SpeedTron\n200", "Marathon\nExtra", "Marathon\n2000"]; #Create a XYChart object of size 450 x 400 pixels my $c = new XYChart(450, 400); #Set the plotarea at (55, 40) and of size 350 x 300 pixels, with a light grey #border (0xc0c0c0). Turn on both horizontal and vertical grid lines with light #grey color (0xc0c0c0) $c->setPlotArea(55, 40, 350, 300, 0xffffff, -1, 0xc0c0c0, 0xc0c0c0, -1); #Add a title to the chart using 18 pts Times Bold Itatic font. $c->addTitle("Product Comparison Chart", "timesbi.ttf", 18); #Add a title to the y axis using 12 pts Arial Bold Italic font $c->yAxis()->setTitle("Capacity (tons)", "arialbi.ttf", 12); #Add a title to the x axis using 12 pts Arial Bold Italic font $c->xAxis()->setTitle("Range (miles)", "arialbi.ttf", 12); #Set the axes line width to 3 pixels $c->xAxis()->setWidth(3); $c->yAxis()->setWidth(3); #Add the data as a scatter chart layer, using a 15 pixel circle as the symbol my $layer = $c->addScatterLayer($dataX, $dataY, "Server BBB", $perlchartdir::CircleSymbol, 15, 0xff3333, 0xff3333); #Add labels to the chart as an extra field $layer->addExtraField($labels); #Set the data label format to display the extra field $layer->setDataLabelFormat("{field0}"); #Use 8pts Arial Bold to display the labels my $textbox = $layer->setDataLabelStyle("arialbd.ttf", 8); #Set the background to purple with a 1 pixel 3D border $textbox->setBackground(0xcc99ff, $perlchartdir::Transparent, 1); #Put the text box 4 pixels to the right of the data point $textbox->setAlignment($perlchartdir::Left); $textbox->setPos(4, 0); #output the chart $c->makeChart("scatterlabels.png")