ChartDirector Ver 4.1 (C++ Edition)

Multi-Line Chart




This example demonstrates a chart with multiple lines of different styles. It also demonstrates using frame with rounded corners, title with glass shading effect, both vertical and horizontal grid lines, and a legend at the top of the plot area.

Source Code Listing

[The following code is available in "cppdemo/multiline". A MFC version of the code is available in "mfcdemo" (Windows edition only).]
#include "chartdir.h"

int main(int argc, char *argv[])
{
    // The data for the line chart
    double data0[] = {42, 49, 33, 38, 51, 46, 29, 41, 44, 57, 59, 52, 37, 34, 51, 56,
        56, 60, 70, 76, 63, 67, 75, 64, 51};
    double data1[] = {50, 55, 47, 34, 42, 49, 63, 62, 73, 59, 56, 50, 64, 60, 67, 67,
        58, 59, 73, 77, 84, 82, 80, 84, 98};
    double data2[] = {36, 28, 25, 33, 38, 20, 22, 30, 25, 33, 30, 24, 28, 15, 21, 26,
        46, 42, 48, 45, 43, 52, 64, 60, 70};

    // The labels for the line chart
    const char *labels[] = {"0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "10",
        "11", "12", "13", "14", "15", "16", "17", "18", "19", "20", "21", "22", "23",
        "24"};

    // Create an XYChart object of size 600 x 300 pixels, with a light blue (EEEEFF)
    // background, black border, 1 pxiel 3D border effect and rounded corners
    XYChart *c = new XYChart(600, 300, 0xeeeeff, 0x000000, 1);
    c->setRoundedFrame();

    // Set the plotarea at (55, 58) and of size 520 x 195 pixels, with white
    // background. Turn on both horizontal and vertical grid lines with light grey
    // color (0xcccccc)
    c->setPlotArea(55, 58, 520, 195, 0xffffff, -1, -1, 0xcccccc, 0xcccccc);

    // Add a legend box at (50, 30) (top of the chart) with horizontal layout. Use 9
    // pts Arial Bold font. Set the background and border color to Transparent.
    c->addLegend(50, 30, false, "arialbd.ttf", 9)->setBackground(Chart::Transparent);

    // Add a title box to the chart using 15 pts Times Bold Italic font, on a light
    // blue (CCCCFF) background with glass effect. white (0xffffff) on a dark red
    // (0x800000) background, with a 1 pixel 3D border.
    c->addTitle("Application Server Throughput", "timesbi.ttf", 15)->setBackground(
        0xccccff, 0x000000, Chart::glassEffect());

    // Add a title to the y axis
    c->yAxis()->setTitle("MBytes per hour");

    // Set the labels on the x axis.
    c->xAxis()->setLabels(StringArray(labels, sizeof(labels)/sizeof(labels[0])));

    // Display 1 out of 3 labels on the x-axis.
    c->xAxis()->setLabelStep(3);

    // Add a title to the x axis
    c->xAxis()->setTitle("Jun 12, 2006");

    // Add a line layer to the chart
    LineLayer *layer = c->addLineLayer();

    // Set the default line width to 2 pixels
    layer->setLineWidth(2);

    // Add the three data sets to the line layer. For demo purpose, we use a dash
    // line color for the last line
    layer->addDataSet(DoubleArray(data0, sizeof(data0)/sizeof(data0[0])), 0xff0000,
        "Server #1");
    layer->addDataSet(DoubleArray(data1, sizeof(data1)/sizeof(data1[0])), 0x008800,
        "Server #2");
    layer->addDataSet(DoubleArray(data2, sizeof(data2)/sizeof(data2[0])),
        c->dashLineColor(0x3333ff, Chart::DashLine), "Server #3");

    // output the chart
    c->makeChart("multiline.png");

    //free up resources
    delete c;
    return 0;
}