Surface Shading

perldemo\surfaceshading.pl
#!/usr/bin/perl

# The ChartDirector for Perl module is assumed to be in "../lib"
use File::Basename;
use lib (dirname($0)."/../lib") =~ /(.*)/;

use perlchartdir;

sub createChart
{
    my $chartIndex = shift;

    # The x and y coordinates of the grid
    my $dataX = [-10, -8, -6, -4, -2, 0, 2, 4, 6, 8, 10];
    my $dataY = [-10, -8, -6, -4, -2, 0, 2, 4, 6, 8, 10];

    # The values at the grid points. In this example, we will compute the values using the formula z
    # = x * sin(y) + y * sin(x).
    my $dataZ = [(0) x (scalar(@$dataX) * scalar(@$dataY))];
    for(my $yIndex = 0; $yIndex < scalar(@$dataY); ++$yIndex) {
        my $y = $dataY->[$yIndex];
        for(my $xIndex = 0; $xIndex < scalar(@$dataX); ++$xIndex) {
            my $x = $dataX->[$xIndex];
            $dataZ->[$yIndex * scalar(@$dataX) + $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.
    my $c = new SurfaceChart(380, 400, 0xffffff, 0x888888);

    # Demonstrate various shading methods
    if ($chartIndex == 0) {
        $c->addTitle("11 x 11 Data Points\nSmooth Shading");
    } elsif ($chartIndex == 1) {
        $c->addTitle("11 x 11 Points - Spline Fitted to 50 x 50\nSmooth Shading");
        $c->setInterpolation(50, 50);
    } elsif ($chartIndex == 2) {
        $c->addTitle("11 x 11 Data Points\nRectangular Shading");
        $c->setShadingMode($perlchartdir::RectangularShading);
    } else {
        $c->addTitle("11 x 11 Data Points\nTriangular Shading");
        $c->setShadingMode($perlchartdir::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
    $c->setData($dataX, $dataY, $dataZ);

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

    # Output the chart
    $c->makeChart("surfaceshading$chartIndex.jpg");
}

createChart(0);
createChart(1);
createChart(2);
createChart(3);