<?php
require_once("../lib/phpchartdir.php");

# The (x, y, z) coordinates of the scattered data
$dataX = array(5.5, 4.9, 2.0, 8.9, 6.8, 5.9, 3.6, 6.8, 3.0, 6.4, 3.9);
$dataY = array(3.3, 3.7, 4.0, 9.3, 4.5, 8.4, 2.8, 2.8, 8.0, 5.7, 4.6);
$dataZ = array(7.5, 9.4, 6.2, 9.6, 13.6, 13.9, 6.2, 6.9, 7.5, 8.7, 9.5);

#create a dummy chart to auto-scale the axis using the z-data, so we can obtain 
#a reasonable  minimum z value and the tick increment for the color axis.
$c = new XYChart(1, 1);
$c->setPlotArea(0, 0, 10, 320);
$c->addLineLayer($dataZ);
$c->yAxis->setAutoScale(0, 0, 0);
$c->layoutAxes();
$ticks = $c->yAxis->getTicks();

$minZScale = $ticks[0];
$maxZScale = $ticks[count($ticks) - 1];
$zInc = $ticks[1] - $ticks[0];

#the border is somewhat below the minimum data value
$borderZ = $minZScale - $zInc * 2;

#create the border outside the chart
for ($i = -1; $i < 11; ++$i)
{
	$dataX[] = -1;
	$dataY[] = $i;
	$dataZ[] = $borderZ;
	
	$dataX[] = 11;
	$dataY[] = $i + 1;
	$dataZ[] = $borderZ;
	
	$dataY[] = -1;
	$dataX[] = $i + 1;
	$dataZ[] = $borderZ;
	
	$dataY[] = 11;
	$dataX[] = $i;
	$dataZ[] = $borderZ;
}
	
# Create a XYChart object of size 450 x 540 pixels
$c = new XYChart(550, 540);

# Add a title to the chart using 15 points Arial Italic font
#$c->addTitle("      Contour Chart with Scattered Data", "ariali.ttf", 15);

# Set the plotarea at (65, 40) and of size 360 x 360 pixels. Use semi-transparent
# black (c0000000) for both horizontal and vertical grid lines
$c->setPlotArea(65, 40, 360, 360, -1, -1, -1, 0xc0000000, -1);
$c->setClipping();

# Set x-axis and y-axis title using 12 points Arial Bold Italic font
$c->xAxis->setTitle("X-Axis Title Place Holder", "arialbi.ttf", 10);
$c->yAxis->setTitle("Y-Axis Title Place Holder", "arialbi.ttf", 10);

# Set x-axis and y-axis labels to use Arial Bold font
$c->xAxis->setLabelStyle("arialbd.ttf");
$c->yAxis->setLabelStyle("arialbd.ttf");

# When x-axis and y-axis color to transparent
$c->xAxis->setColors(Transparent);
$c->yAxis->setColors(Transparent);
$c->xAxis->setLinearScale(0, 10, 1);
$c->yAxis->setLinearScale(0, 10, 1);

# Add a scatter layer to the chart to show the position of the data points
$c->addScatterLayer($dataX, $dataY, "", Cross2Shape(0.2), 7, 0x000000);

# Add a contour layer using the given data
$layer = $c->addContourLayer($dataX, $dataY, $dataZ);

# Set the contour color to transparent
$layer->setContourColor(Transparent);
#$layer->setSmoothInterpolation(false);

# Move the grid lines in front of the contour layer
$plotAreaObj = $c->getPlotArea();
$plotAreaObj->moveGridBefore($layer);

# Add a color axis (the legend) in which the top center is anchored at (245, 455).
# Set the length to 330 pixels and the labels on the top side.
$cAxis = $layer->setColorAxis(450, 40, TopLeft, 330, Right);

# Add a bounding box to the color axis using the default line color as border.
$cAxis->setBoundingBox(Transparent, LineColor);

# Set color axis labels to use Arial Bold font
$cAxis->setLabelStyle("arialbd.ttf");

# The color axis scale
$cAxis->setLinearScale($minZScale - $zInc, $maxZScale, $zInc);

# The color gradient includes the white color as the minimum color.
$cAxis->setColorGradient(true, array(0xffffff, 0xC0, 0x60FF, 0xC0FF, 0x00FFFF, 0x30FFC0, 
			0x60FF90, 0x90FF60, 0xC0FF30, 0xFFFF00, 0xFFCC00, 0xFF8800, 0xFF5500, 0xFF0000));

# Output the chart
header("Content-type: image/png");
print($c->makeChart2(PNG));
?>