- Add possibility to use filled line charts

2 files changed, 154 insertions, 1 deletions

diff --git a/src/charts/line.php b/src/charts/line.php
index 9d3d499..60935de 100644
--- a/src/charts/line.php
+++ b/src/charts/line.php
@@ -73,7 +73,15 @@ class ezcGraphLineChart extends ezcGraphChart
     {
         foreach ( $this->data as $data )
         {
+            if ( $this->options->fillLines !== false )
+            {
+                $fillColor = clone $data->color->default;
+                $fillColor->alpha = (int) round( ( 255 - $fillColor->alpha ) * ( $this->options->fillLines / 255 ) );
+            }
+
             $lastPoint = false;
+            $lastKey = false;
+            $lastValue = false;
             foreach ( $data as $key => $value )
             {
                 $point = new ezcGraphCoordinate( 
@@ -81,6 +89,71 @@ class ezcGraphLineChart extends ezcGraphChart
                     (int) round( $this->elements['Y_axis']->getCoordinate( $boundings, $value ) )
                 );
 
+                // Fill the line
+                if ( $lastPoint !== false && $this->options->fillLines !== false )
+                {
+                    $axisPosition = (int) round( $this->elements['Y_axis']->getCoordinate( $boundings, false ) );
+
+                    $lastAxisPoint = new ezcGraphCoordinate(
+                        (int) round( $this->elements['X_axis']->getCoordinate( $boundings, $lastKey ) ),
+                        $axisPosition
+                    );
+                    $axisPoint = new ezcGraphCoordinate(
+                        (int) round( $this->elements['X_axis']->getCoordinate( $boundings, $key ) ),
+                        $axisPosition
+                    );
+
+                    if ( $value / abs( $value ) == $lastValue / abs( $lastValue ) )
+                    {
+                        // Values have the same sign, so that the line do not cross any axes
+                        $renderer->drawPolygon(
+                            array(
+                                $lastPoint,
+                                $point,
+                                $axisPoint,
+                                $lastAxisPoint,
+                            ),
+                            $fillColor,
+                            true
+                        );
+                    }
+                    else
+                    {
+                        // Draw two polygones to consider cutting point with axis
+                        $diffOne = abs( $axisPosition - $lastPoint->y );
+                        $diffTwo = abs( $axisPosition - $point->y );
+
+                        // Switch values, if first is greater then second
+                        $cuttingPosition = $diffOne / ( $diffTwo + $diffOne );
+                        
+                        // Calculate cutting point
+                        $cuttingPoint = new ezcGraphCoordinate(
+                            (int) round( $lastAxisPoint->x + ( $axisPoint->x - $lastAxisPoint->x ) * $cuttingPosition ),
+                            $axisPosition
+                        );
+
+                        // Finally draw polygons
+                        $renderer->drawPolygon(
+                            array(
+                                $lastPoint,
+                                $cuttingPoint,
+                                $lastAxisPoint,
+                            ),
+                            $fillColor,
+                            true
+                        );
+                        $renderer->drawPolygon(
+                            array(
+                                $point,
+                                $cuttingPoint,
+                                $axisPoint,
+                            ),
+                            $fillColor,
+                            true
+                        );
+                    }
+                }
+
                 // Draw line
                 if ( $lastPoint !== false )
                 {
@@ -113,6 +186,8 @@ class ezcGraphLineChart extends ezcGraphChart
                 }
 
                 $lastPoint = $point;
+                $lastValue = $value;
+                $lastKey = $key;
             }
         }
     }
diff --git a/tests/line_test.php b/tests/line_test.php
index 7f32ff0..28fae16 100644
--- a/tests/line_test.php
+++ b/tests/line_test.php
@@ -99,7 +99,7 @@ class ezcGraphLineChartTest extends ezcTestCase
     public function testRenderChartLines()
     {
         $chart = ezcGraph::create( 'Line' );
-        $chart->sampleData = array( 'sample 1' => 234, 'sample 2' => 21, 'sample 3' => 324, 'sample 4' => 120, 'sample 5' => 1);
+        $chart->sampleData = array( 'sample 1' => 234, 'sample 2' => 21, 'sample 3' => 324, 'sample 4' => 120, 'sample 5' => 1 );
         $chart->sampleData->color = '#CC0000';
         $chart->sampleData->symbol = ezcGraph::DIAMOND;
 
@@ -149,6 +149,84 @@ class ezcGraphLineChartTest extends ezcTestCase
         $chart->render( 500, 200 );
     }
 
+    public function testRenderChartFilledLines()
+    {
+        $chart = ezcGraph::create( 'Line' );
+        $chart->sampleData = array( 'sample 1' => 234, 'sample 2' => 21, 'sample 3' => -46, 'sample 4' => 120 );
+        $chart->palette = 'Black';
+        $chart->options->fillLines = 100;
+
+        $mockedRenderer = $this->getMock( 'ezcGraphRenderer2D', array(
+            'drawPolygon',
+        ) );
+
+        $mockedRenderer
+            ->expects( $this->at( 2 ) )
+            ->method( 'drawPolygon' )
+            ->with(
+                $this->equalTo( array( 
+                    new ezcGraphCoordinate( 120, 40 ),
+                    new ezcGraphCoordinate( 240, 136 ),
+                    new ezcGraphCoordinate( 240, 145 ),
+                    new ezcGraphCoordinate( 120, 145 ),
+                ) ),
+                $this->equalTo( ezcGraphColor::fromHex( '#3465A464' ) ),
+                $this->equalTo( true )
+            );
+        $mockedRenderer
+            ->expects( $this->at( 3 ) )
+            ->method( 'drawPolygon' )
+            ->with(
+                $this->equalTo( array( 
+                    new ezcGraphCoordinate( 240, 136 ),
+                    new ezcGraphCoordinate( 276, 145 ),
+                    new ezcGraphCoordinate( 240, 145 ),
+                ) ),
+                $this->equalTo( ezcGraphColor::fromHex( '#3465A464' ) ),
+                $this->equalTo( true )
+            );
+        $mockedRenderer
+            ->expects( $this->at( 4 ) )
+            ->method( 'drawPolygon' )
+            ->with(
+                $this->equalTo( array( 
+                    new ezcGraphCoordinate( 360, 166 ),
+                    new ezcGraphCoordinate( 276, 145 ),
+                    new ezcGraphCoordinate( 360, 145 ),
+                ) ),
+                $this->equalTo( ezcGraphColor::fromHex( '#3465A464' ) ),
+                $this->equalTo( true )
+            );
+        $mockedRenderer
+            ->expects( $this->at( 5 ) )
+            ->method( 'drawPolygon' )
+            ->with(
+                $this->equalTo( array( 
+                    new ezcGraphCoordinate( 360, 166 ),
+                    new ezcGraphCoordinate( 394, 145 ),
+                    new ezcGraphCoordinate( 360, 145 ),
+                ) ),
+                $this->equalTo( ezcGraphColor::fromHex( '#3465A464' ) ),
+                $this->equalTo( true )
+            );
+        $mockedRenderer
+            ->expects( $this->at( 6 ) )
+            ->method( 'drawPolygon' )
+            ->with(
+                $this->equalTo( array( 
+                    new ezcGraphCoordinate( 480, 91 ),
+                    new ezcGraphCoordinate( 394, 145 ),
+                    new ezcGraphCoordinate( 480, 145 ),
+                ) ),
+                $this->equalTo( ezcGraphColor::fromHex( '#3465A464' ) ),
+                $this->equalTo( true )
+            );
+
+        $chart->renderer = $mockedRenderer;
+
+        $chart->render( 500, 200 );
+    }
+
     public function testRenderChartLinesModifiedThickness()
     {
         $chart = ezcGraph::create( 'Line' );