ChartDirector Ver 3.0 (C++ Edition)

Polar Line Chart




This example demonstratea a polar line chart, completed with data symbols and data labels.

Source Code Listing

[The following project is available in "cppdemo/polarline".]
#include "chartdir.h" int main(int argc, char *argv[]) { //The data for the chart double data0[] = {90, 25, 40, 55, 68, 44, 79, 85, 50}; double angles0[] = {15, 60, 110, 180, 230, 260, 260, 310, 340}; double data1[] = {80, 91, 66, 80, 92, 87}; double angles1[] = {40, 65, 88, 110, 150, 200}; //Create a PolarChart object of size 460 x 460 pixels PolarChart *c = new PolarChart(460, 460); //Add a title to the chart at the top left corner using 15pts Arial Bold //Italic font c->addTitle(TopLeft, "<*underline=2*>Polar Line Chart Demo", "arialbi.ttf", 15); //Set center of plot area at (230, 240) with radius 180 pixels c->setPlotArea(230, 240, 180); //Set the grid style to circular grid, with grids below the chart layers c->setGridStyle(false, false); //Add a legend box at the top right corner of the chart using 9 pts Arial //Bold font c->addLegend(459, 0, true, "arialbd.ttf", 9)->setAlignment(TopRight); //Set angular axis as 0 - 360, either spoke every 30 units c->angularAxis()->setLinearScale(0, 360, 30); //Add a blue (0xff) line layer to the chart using (data0, angle0) PolarLineLayer *layer0 = c->addLineLayer(DoubleArray(data0, sizeof(data0)/sizeof(*data0)), 0xff, "Close Loop Line"); layer0->setAngles(DoubleArray(angles0, sizeof(angles0)/sizeof(*angles0))); //Set the line width to 2 pixels layer0->setLineWidth(2); //Use 11 pixel triangle symbols for the data points layer0->setDataSymbol(TriangleSymbol, 11); //Enable data label and set its format layer0->setDataLabelFormat("({value},{angle})"); //Set the data label text box with light blue (0x9999ff) backgruond color //and 1 pixel 3D border effect layer0->setDataLabelStyle()->setBackground(0x9999ff, Transparent, 1); //Add a red (0xff0000) line layer to the chart using (data1, angle1) PolarLineLayer *layer1 = c->addLineLayer(DoubleArray(data1, sizeof(data1)/sizeof(*data1)), 0xff0000, "Open Loop Line"); layer1->setAngles(DoubleArray(angles1, sizeof(angles1)/sizeof(*angles1))); //Set the line width to 2 pixels layer1->setLineWidth(2); //Use 11 pixel diamond symbols for the data points layer1->setDataSymbol(DiamondSymbol, 11); //Set the line to open loop layer1->setCloseLoop(false); //Enable data label and set its format layer1->setDataLabelFormat("({value},{angle})"); //Set the data label text box with light red (0xff9999) backgruond color and //1 pixel 3D border effect layer1->setDataLabelStyle()->setBackground(0xff9999, Transparent, 1); //output the chart c->makeChart("polarline.png"); //free up resources delete c; return 0; }