Surface Shading

The following is the command line version of the code in "cppdemo/surfaceshading". The MFC version of the code is in "mfcdemo/mfcdemo". The Qt Widgets version of the code is in "qtdemo/qtdemo". The QML/Qt Quick version of the code is in "qmldemo/qmldemo".
#include "chartdir.h"
#include <math.h>

void createChart(int chartIndex, const char *filename)
{
    // The x and y coordinates of the grid
    double dataX[] = {-10, -8, -6, -4, -2, 0, 2, 4, 6, 8, 10};
    const int dataX_size = (int)(sizeof(dataX)/sizeof(*dataX));
    double dataY[] = {-10, -8, -6, -4, -2, 0, 2, 4, 6, 8, 10};
    const int dataY_size = (int)(sizeof(dataY)/sizeof(*dataY));

    // The values at the grid points. In this example, we will compute the values using the formula
    // z = x * sin(y) + y * sin(x).
    const int dataZ_size = dataX_size * dataY_size;
    double dataZ[dataZ_size];
    for(int yIndex = 0; yIndex < dataY_size; ++yIndex) {
        double y = dataY[yIndex];
        for(int xIndex = 0; xIndex < dataX_size; ++xIndex) {
            double x = dataX[xIndex];
            dataZ[yIndex * dataX_size + xIndex] = x * sin(y) + y * sin(x);
        }
    }

    // Create a SurfaceChart object of size 380 x 400 pixels, with white (ffffff) background and
    // grey (888888) border.
    SurfaceChart* c = new SurfaceChart(380, 400, 0xffffff, 0x888888);

    // Demonstrate various shading methods
    if (chartIndex == 0) {
        c->addTitle("11 x 11 Data Points\nSmooth Shading");
    } else if (chartIndex == 1) {
        c->addTitle("11 x 11 Points - Spline Fitted to 50 x 50\nSmooth Shading");
        c->setInterpolation(50, 50);
    } else if (chartIndex == 2) {
        c->addTitle("11 x 11 Data Points\nRectangular Shading");
        c->setShadingMode(Chart::RectangularShading);
    } else {
        c->addTitle("11 x 11 Data Points\nTriangular Shading");
        c->setShadingMode(Chart::TriangularShading);
    }

    // Set the center of the plot region at (175, 200), and set width x depth x height to 200 x 200
    // x 160 pixels
    c->setPlotRegion(175, 200, 200, 200, 160);

    // Set the plot region wall thichness to 5 pixels
    c->setWallThickness(5);

    // Set the elevation and rotation angles to 45 and 60 degrees
    c->setViewAngle(45, 60);

    // Set the perspective level to 35
    c->setPerspective(35);

    // Set the data to use to plot the chart
    c->setData(DoubleArray(dataX, dataX_size), DoubleArray(dataY, dataY_size), DoubleArray(dataZ,
        dataZ_size));

    // Set contour lines to semi-transparent black (c0000000)
    c->setContourColor(0xc0000000);

    // Output the chart
    c->makeChart(filename);

    //free up resources
    delete c;

}

int main(int argc, char *argv[])
{
    createChart(0, "surfaceshading0.jpg");
    createChart(1, "surfaceshading1.jpg");
    createChart(2, "surfaceshading2.jpg");
    createChart(3, "surfaceshading3.jpg");
    return 0;
}