This example demonstrates using bar gradient shading for a horizontal bar chart. It also demonstrates using gradient color background, partially rounded frame, and automatic resizing of the plot area to fit the chart.
perldemo\gradientbar.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;
# The data for the bar chart
my $data = [1350, 1600, 1950, 2300, 2700];
# The labels for the bar chart
my $labels = ["2001", "2002", "2003", "2004", "2005"];
# The colors for the bars
my $colors = [0xcc0000, 0x66aaee, 0xeebb22, 0xcccccc, 0xcc88ff];
# Create a PieChart object of size 600 x 380 pixels.
my $c = new XYChart(600, 380);
# Use the white on black palette, which means the default text and line colors are white
$c->setColors($perlchartdir::whiteOnBlackPalette);
# Use a vertical gradient color from blue (0000cc) to deep blue (000044) as background. Use rounded
# corners of 30 pixels radius for the top-left and bottom-right corners.
$c->setBackground($c->linearGradientColor(0, 0, 0, $c->getHeight(), 0x0000cc, 0x000044));
$c->setRoundedFrame(0xffffff, 30, 0, 30, 0);
# Add a title using 18pt Times New Roman Bold Italic font. Add 6 pixels top and bottom margins to
# the title.
my $title = $c->addTitle("Annual Revenue for Star Tech", "Times New Roman Bold Italic", 18);
$title->setMargin2(0, 0, 6, 6);
# Add a separator line in white color just under the title
$c->addLine(20, $title->getHeight(), $c->getWidth() - 21, $title->getHeight(), 0xffffff);
# Tentatively set the plotarea at (70, 80) and of 480 x 240 pixels in size. Use transparent border
# and white grid lines
$c->setPlotArea(70, 80, 480, 240, -1, -1, $perlchartdir::Transparent, 0xffffff);
# Swap the axis so that the bars are drawn horizontally
$c->swapXY();
# Add a multi-color bar chart layer using the supplied data. Use bar gradient lighting with the
# light intensity from 0.75 to 2.0
$c->addBarLayer3($data, $colors)->setBorderColor($perlchartdir::Transparent,
perlchartdir::barLighting(0.75, 2.0));
# Set the labels on the x axis.
$c->xAxis()->setLabels($labels);
# Show the same scale on the left and right y-axes
$c->syncYAxis();
# Set the bottom y-axis title using 10pt Arial Bold font
$c->yAxis()->setTitle("USD (millions)", "Arial Bold", 10);
# Set y-axes to transparent
$c->yAxis()->setColors($perlchartdir::Transparent);
$c->yAxis2()->setColors($perlchartdir::Transparent);
# Disable ticks on the x-axis by setting the tick color to transparent
$c->xAxis()->setTickColor($perlchartdir::Transparent);
# Set the label styles of all axes to 8pt Arial Bold font
$c->xAxis()->setLabelStyle("Arial Bold", 8);
$c->yAxis()->setLabelStyle("Arial Bold", 8);
$c->yAxis2()->setLabelStyle("Arial Bold", 8);
# Adjust the plot area size, such that the bounding box (inclusive of axes) is 30 pixels from the
# left edge, 25 pixels below the title, 50 pixels from the right edge, and 25 pixels from the bottom
# edge.
$c->packPlotArea(30, $title->getHeight() + 25, $c->getWidth() - 50, $c->getHeight() - 25);
# Output the chart
$c->makeChart("gradientbar.png");
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