ChartDirector 5.1 (C++ Edition)

Symbol Line Chart (2)




This example demonstrates using symbols to represent data points and using gradient color for plot area background.

Source Code Listing

[The following code is available in "cppdemo/symbolline2". A MFC version of the code is available in "mfcdemo/mfcdemo" (Windows edition only). A QT version of the code is available in "qtdemo/qtdemo".]
#include "chartdir.h"

int main(int argc, char *argv[])
{
    // The data for the line chart
    double data0[] = {42, 49, 33, 38, 64, 56, 29, 41, 44, 57, 59, 42};
    double data1[] = {65, 75, 47, 34, 42, 49, 73, 62, 90, 69, 66, 78};
    double data2[] = {36, 28, 25, 28, 38, 20, 22, 30, 25, 33, 30, 24};
    const char *labels[] = {"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug",
        "Sep", "Oct", "Nov", "Dec"};

    // Create a XYChart object of size 600 x 375 pixels
    XYChart *c = new XYChart(600, 375);

    // Add a title to the chart using 18 pts Times Bold Italic font
    c->addTitle("Product Line Global Revenue", "timesbi.ttf", 18);

    // Set the plotarea at (50, 55) and of 500 x 280 pixels in size. Use a vertical
    // gradient color from light blue (f9f9ff) to sky blue (aaccff) as background.
    // Set border to transparent and grid lines to white (ffffff).
    c->setPlotArea(50, 55, 500, 280, c->linearGradientColor(0, 55, 0, 335, 0xf9fcff,
        0xaaccff), -1, Chart::Transparent, 0xffffff);

    // Add a legend box at (50, 28) using horizontal layout. Use 10pts Arial Bold as
    // font, with transparent background.
    c->addLegend(50, 28, false, "arialbd.ttf", 10)->setBackground(Chart::Transparent)
        ;

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

    // Set y-axis tick density to 30 pixels. ChartDirector auto-scaling will use this
    // as the guideline when putting ticks on the y-axis.
    c->yAxis()->setTickDensity(30);

    // Set axis label style to 8pts Arial Bold
    c->xAxis()->setLabelStyle("arialbd.ttf", 8);
    c->yAxis()->setLabelStyle("arialbd.ttf", 8);

    // Set axis line width to 2 pixels
    c->xAxis()->setWidth(2);
    c->yAxis()->setWidth(2);

    // Add axis title using 10pts Arial Bold Italic font
    c->yAxis()->setTitle("Revenue in USD millions", "arialbi.ttf", 10);

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

    // Set the line width to 3 pixels
    layer->setLineWidth(3);

    // Add the three data sets to the line layer, using circles, diamands and X
    // shapes as symbols
    layer->addDataSet(DoubleArray(data0, (int)(sizeof(data0) / sizeof(data0[0]))),
        0xff0000, "Quantum Computer")->setDataSymbol(Chart::CircleSymbol, 9);
    layer->addDataSet(DoubleArray(data1, (int)(sizeof(data1) / sizeof(data1[0]))),
        0x00ff00, "Atom Synthesizer")->setDataSymbol(Chart::DiamondSymbol, 11);
    layer->addDataSet(DoubleArray(data2, (int)(sizeof(data2) / sizeof(data2[0]))),
        0xff6600, "Proton Cannon")->setDataSymbol(Chart::Cross2Shape(), 11);

    // Output the chart
    c->makeChart("symbolline2.png");

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