- Added tests and basic implementation for pie charts

1 files changed, 179 insertions, 0 deletions

diff --git a/src/charts/pie.php b/src/charts/pie.php
index 49044b0..118be7c 100644
--- a/src/charts/pie.php
+++ b/src/charts/pie.php
@@ -14,6 +14,18 @@
  */
 class ezcGraphPieChart extends ezcGraphChart
 {
+    
+    protected $maxLabelHeight = .15;
+
+    protected $label = '%1$s: %2$d (%3$.1f%%)';
+
+    public function __construct( array $options = array() )
+    {
+        $this->options = new ezcGraphChartOptions( $options );
+
+        parent::__construct( $options );
+    }
+
     /**
      * Adds a dataset to the charts data
      * 
@@ -33,6 +45,142 @@ class ezcGraphPieChart extends ezcGraphChart
         else
         {
             parent::addDataSet( $name, $values );
+
+            // Colorize each data element
+            foreach ( $this->data[$name] as $label => $value )
+            {
+                $this->data[$name]->color[$label] = $this->palette->dataSetColor;
+            }
+        }
+    }
+
+    protected function renderData( $renderer, $boundings )
+    {
+        // Only draw the first (and only) dataset
+        $dataset = reset( $this->data );
+
+        $this->driver->options->font = $this->options->font;
+
+        // Calculate sum of all values to be able to calculate percentage
+        $sum = 0;
+        foreach ( $dataset as $value )
+        {
+            $sum += $value;
+        }
+    
+        // Calculate position and size of pie
+        $center = new ezcGraphCoordinate(
+            (int) round( $boundings->x0 + ( $boundings->x1 - $boundings->x0 ) / 2 ),
+            (int) round( $boundings->y0 + ( $boundings->y1 - $boundings->y0 ) / 2 )
+        );
+        $radius = min(
+            $boundings->x1 - $boundings->x0,
+            $boundings->y1 - $boundings->y0
+        ) / 2;
+
+        // Draw all data
+        $angle = 0.;
+        $labels = array();
+        foreach ( $dataset as $label => $value )
+        {
+            $renderer->drawPieSegment(
+                $dataset->color[$label],
+                $center,
+                $radius,
+                $angle,
+                $endAngle = $angle + $value / $sum * 360,
+                0
+            );
+
+            // Determine position of label
+            $middle = $angle + ( $endAngle - $angle ) / 2;
+            $pieSegmentCenter = new ezcGraphCoordinate(
+                (int) round( cos( deg2rad( $middle ) ) * $radius + $center->x ),
+                (int) round( sin( deg2rad( $middle ) ) * $radius + $center->y )
+            );
+
+            // Split labels up into left an right size and index them on their
+            // y position
+            $labels[(int) ($pieSegmentCenter->x > $center->x)][$pieSegmentCenter->y] = array(
+                new ezcGraphCoordinate(
+                    (int) round( cos( deg2rad( $middle ) ) * $radius * 2 / 3 + $center->x ),
+                    (int) round( sin( deg2rad( $middle ) ) * $radius * 2 / 3 + $center->y )
+                ),
+                sprintf( $this->label, $label, $value, $value * 100 / $sum )
+            );
+            $angle = $endAngle;
+        }
+
+        $labelHeight = (int) round( min(
+            ( $boundings->y1 - $boundings->y0 ) / count( $labels[0] ),
+            ( $boundings->y1 - $boundings->y0 ) / count( $labels[1] ),
+            ( $boundings->y1 - $boundings->y0 ) * $this->maxLabelHeight
+        ) );
+        
+        $symbolSize = 6;
+
+        // Finally draw labels
+        foreach ( $labels as $side => $labelPart )
+        {
+            $minHeight = $boundings->y0;
+            $toShare = ( $boundings->y1 - $boundings->y0 ) - count( $labelPart ) * $labelHeight;
+
+            // Sort to draw topmost label first
+            ksort( $labelPart );
+            $sign = ( $side ? -1 : 1 );
+
+            foreach ( $labelPart as $height => $label )
+            {
+                // Determine position of label
+                $minHeight += round( max( 0, $height - $minHeight ) / ( $boundings->y1 - $boundings->y0 ) * $toShare );
+                $labelPosition = new ezcGraphCoordinate(
+                    (int) round( $center->x - $sign * ( cos ( asin ( ( $center->y - $minHeight - $labelHeight / 2 ) / $radius ) ) * $radius + $symbolSize ) ),
+                    (int) round( $minHeight + $labelHeight / 2 )
+                );
+
+                // Draw label
+                $renderer->drawLine(
+                    $this->options->font->color,
+                    $label[0],
+                    $labelPosition,
+                    false
+                );
+
+                $renderer->drawSymbol(
+                    $this->options->font->color,
+                    new ezcGraphCoordinate(
+                        $label[0]->x - $symbolSize / 2,
+                        $label[0]->y - $symbolSize / 2
+                    ),
+                    $symbolSize,
+                    $symbolSize,
+                    ezcGraph::BULLET
+                );
+                $renderer->drawSymbol(
+                    $this->options->font->color,
+                    new ezcGraphCoordinate(
+                        $labelPosition->x - $symbolSize / 2,
+                        $labelPosition->y - $symbolSize / 2
+                    ),
+                    $symbolSize,
+                    $symbolSize,
+                    ezcGraph::BULLET
+                );
+
+                $renderer->drawTextBox(
+                    new ezcGraphCoordinate(
+                        ( !$side ? $boundings->x0 : $labelPosition->x + $symbolSize ),
+                        $minHeight
+                    ),
+                    $label[1],
+                    (int) round( !$side ? $labelPosition->x - $boundings->x0 - $symbolSize : $boundings->x1 - $labelPosition->x - $symbolSize ),
+                    $labelHeight,
+                    ( !$side ? ezcGraph::RIGHT : ezcGraph::LEFT ) | ezcGraph::MIDDLE
+                );
+
+                // Add used space to minHeight
+                $minHeight += $labelHeight;
+            }
         }
     }
 
@@ -45,8 +193,39 @@ class ezcGraphPieChart extends ezcGraphChart
      */
     public function render( $width, $height, $file = null )
     {
+        // Set image properties in driver
+        $this->driver->options->width = $width;
+        $this->driver->options->height = $height;
+
         // Generate legend
         $this->elements['legend']->generateFromDataset( reset( $this->data ) );
+
+        // Get boundings from parameters
+        $this->options->width = $width;
+        $this->options->height = $height;
+
+        // Render subelements
+        $boundings = new ezcGraphBoundings();
+        $boundings->x1 = $this->options->width;
+        $boundings->y1 = $this->options->height;
+
+        // Render border and background
+        $boundings = $this->renderBorder( $boundings );
+        $boundings = $this->renderBackground( $boundings );
+
+        foreach ( $this->elements as $name => $element )
+        {
+            $this->driver->options->font = $element->font;
+            $boundings = $element->render( $this->renderer, $boundings );
+        }
+
+        // Render graph
+        $this->renderData( $this->renderer, $boundings );
+
+        if ( !empty( $file ) )
+        {
+            $this->renderer->render( $file );
+        }
     }
 }