ChartDirector 7.0 (Perl Edition)

Gradient Bar Shading




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.

Source Code Listing

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");