/**
  * Render the text
  * 
  * @param ezcGraphRenderer $renderer Renderer
  * @param ezcGraphBoundings $boundings Boundings for the axis
  * @return ezcGraphBoundings Remaining boundings
  */
 public function render(ezcGraphRenderer $renderer, ezcGraphBoundings $boundings)
 {
     $height = (int) min(round($this->properties['maxHeight'] * ($boundings->y1 - $boundings->y0)), $this->properties['font']->maxFontSize + $this->padding * 2 + $this->margin * 2);
     switch ($this->properties['position']) {
         case ezcGraph::TOP:
             $textBoundings = new ezcGraphBoundings($boundings->x0, $boundings->y0, $boundings->x1, $boundings->y0 + $height);
             $boundings->y0 += $height + $this->properties['margin'];
             break;
         case ezcGraph::BOTTOM:
             $textBoundings = new ezcGraphBoundings($boundings->x0, $boundings->y1 - $height, $boundings->x1, $boundings->y1);
             $boundings->y1 -= $height + $this->properties['margin'];
             break;
     }
     $textBoundings = $renderer->drawBox($textBoundings, $this->properties['background'], $this->properties['border'], $this->properties['borderWidth'], $this->properties['margin'], $this->properties['padding']);
     $renderer->drawText($textBoundings, $this->properties['title'], ezcGraph::CENTER | ezcGraph::MIDDLE);
     return $boundings;
 }

 /**
  * Render Axis labels
  *
  * Render labels for an axis.
  *
  * @param ezcGraphRenderer $renderer Renderer used to draw the chart
  * @param ezcGraphBoundings $boundings Boundings of the axis
  * @param ezcGraphCoordinate $start Axis starting point
  * @param ezcGraphCoordinate $end Axis ending point
  * @param ezcGraphChartElementAxis $axis Axis instance
  * @return void
  */
 public function renderLabels(ezcGraphRenderer $renderer, ezcGraphBoundings $boundings, ezcGraphCoordinate $start, ezcGraphCoordinate $end, ezcGraphChartElementAxis $axis)
 {
     // receive rendering parameters from axis
     $steps = $axis->getSteps();
     $this->steps = $steps;
     $axisBoundings = new ezcGraphBoundings($start->x, $start->y, $end->x, $end->y);
     // Determine normalized axis direction
     $this->direction = new ezcGraphVector($start->x - $end->x, $start->y - $end->y);
     $this->direction->unify();
     if ($this->outerGrid) {
         $gridBoundings = $boundings;
     } else {
         $gridBoundings = new ezcGraphBoundings($boundings->x0 + $renderer->xAxisSpace * abs($this->direction->y), $boundings->y0 + $renderer->yAxisSpace * abs($this->direction->x), $boundings->x1 - $renderer->xAxisSpace * abs($this->direction->y), $boundings->y1 - $renderer->yAxisSpace * abs($this->direction->x));
     }
     // Determine additional required axis space by boxes
     $firstStep = reset($steps);
     $lastStep = end($steps);
     $this->widthModifier = 1 + $firstStep->width / 2 + $lastStep->width / 2;
     // Draw steps and grid
     foreach ($steps as $nr => $step) {
         $position = new ezcGraphCoordinate($start->x + ($end->x - $start->x) * ($step->position + $step->width) / $this->widthModifier, $start->y + ($end->y - $start->y) * ($step->position + $step->width) / $this->widthModifier);
         $stepWidth = $step->width / $this->widthModifier;
         $stepSize = new ezcGraphCoordinate($axisBoundings->width * $stepWidth, $axisBoundings->height * $stepWidth);
         if ($this->showLabels) {
             // Calculate label boundings
             switch (true) {
                 case abs($this->direction->x) > abs($this->direction->y) && $this->direction->x <= 0:
                     $labelBoundings = new ezcGraphBoundings($position->x - $stepSize->x + $this->labelPadding, $position->y + $this->labelPadding, $position->x - $this->labelPadding, $position->y + $renderer->yAxisSpace - $this->labelPadding);
                     $alignement = ezcGraph::CENTER | ezcGraph::TOP;
                     break;
                 case abs($this->direction->x) > abs($this->direction->y) && $this->direction->x > 0:
                     $labelBoundings = new ezcGraphBoundings($position->x + $this->labelPadding, $position->y + $this->labelPadding, $position->x + $stepSize->x - $this->labelPadding, $position->y + $renderer->yAxisSpace - $this->labelPadding);
                     $alignement = ezcGraph::CENTER | ezcGraph::TOP;
                     break;
                 case $this->direction->y <= 0:
                     $labelBoundings = new ezcGraphBoundings($position->x - $renderer->xAxisSpace + $this->labelPadding, $position->y - $stepSize->y + $this->labelPadding, $position->x - $this->labelPadding, $position->y - $this->labelPadding);
                     $alignement = ezcGraph::MIDDLE | ezcGraph::RIGHT;
                     break;
                 case $this->direction->y > 0:
                     $labelBoundings = new ezcGraphBoundings($position->x - $renderer->xAxisSpace + $this->labelPadding, $position->y + $this->labelPadding, $position->x - $this->labelPadding, $position->y + $stepSize->y - $this->labelPadding);
                     $alignement = ezcGraph::MIDDLE | ezcGraph::RIGHT;
                     break;
             }
             $renderer->drawText($labelBoundings, $step->label, $alignement);
         }
         // major grid
         if ($axis->majorGrid) {
             $this->drawGrid($renderer, $gridBoundings, $position, $stepSize, $axis->majorGrid);
         }
         // major step
         $this->drawStep($renderer, $position, $this->direction, $axis->position, $this->majorStepSize, $axis->border);
     }
 }

 /**
  * Render the assigned data
  *
  * Will renderer all charts data in the remaining boundings after drawing 
  * all other chart elements. The data will be rendered depending on the 
  * settings in the dataset.
  * 
  * @param ezcGraphRenderer $renderer Renderer
  * @param ezcGraphBoundings $boundings Remaining boundings
  * @return void
  */
 protected function renderData(ezcGraphRenderer $renderer, ezcGraphBoundings $boundings)
 {
     // Only draw the first (and only) dataset
     $dataset = $this->data->rewind();
     $datasetName = $this->data->key();
     $this->driver->options->font = $this->options->font;
     // Calculate sum of all values to be able to calculate percentage
     $sum = 0;
     foreach ($dataset as $name => $value) {
         if ($value < 0) {
             throw new ezcGraphInvalidDataException("Values >= 0 required, '{$name}' => '{$value}'.");
         }
         $sum += $value;
     }
     if ($this->options->sum !== false) {
         $sum = max($sum, $this->options->sum);
     }
     if ($sum <= 0) {
         throw new ezcGraphInvalidDataException("Pie charts require a value sum > 0, your value: '{$sum}'.");
     }
     $angle = 0;
     foreach ($dataset as $label => $value) {
         // Skip rendering values which equals 0
         if ($value <= 0) {
             continue;
         }
         switch ($dataset->displayType->default) {
             case ezcGraph::PIE:
                 $displayLabel = $this->options->labelCallback !== null ? call_user_func($this->options->labelCallback, $label, $value, $value / $sum) : sprintf($this->options->label, $label, $value, $value / $sum * 100);
                 $renderer->drawPieSegment($boundings, new ezcGraphContext($datasetName, $label, $dataset->url[$label]), $dataset->color[$label], $angle, $angle += $value / $sum * 360, $displayLabel, $dataset->highlight[$label]);
                 break;
             default:
                 throw new ezcGraphInvalidDisplayTypeException($dataset->displayType->default);
                 break;
         }
     }
 }

 /**
  * Render the background
  *
  * @param ezcGraphRenderer $renderer Renderer
  * @param ezcGraphBoundings $boundings Boundings
  * @return ezcGraphBoundings Remaining boundings
  */
 public function render(ezcGraphRenderer $renderer, ezcGraphBoundings $boundings)
 {
     $boundings = $renderer->drawBox($boundings, $this->background, $this->border, $this->borderWidth, $this->margin, $this->padding);
     if ($this->image === false) {
         return $boundings;
     }
     $renderer->drawBackgroundImage($boundings, $this->image, $this->position, $this->repeat);
     return $boundings;
 }

 /**
  * Render the assigned data
  *
  * Will renderer all charts data in the remaining boundings after drawing 
  * all other chart elements. The data will be rendered depending on the 
  * settings in the dataset.
  * 
  * @param ezcGraphRenderer $renderer Renderer
  * @param ezcGraphBoundings $boundings Remaining boundings
  * @return void
  */
 protected function renderData(ezcGraphRenderer $renderer, ezcGraphBoundings $boundings, ezcGraphBoundings $innerBoundings)
 {
     // Use inner boundings for drawning chart data
     $boundings = $innerBoundings;
     $yAxisNullPosition = $this->elements['xAxis']->getCoordinate(false);
     // Initialize counters
     $nr = array();
     $count = array();
     foreach ($this->data as $data) {
         if (!isset($nr[$data->displayType->default])) {
             $nr[$data->displayType->default] = 0;
             $count[$data->displayType->default] = 0;
         }
         $nr[$data->displayType->default]++;
         $count[$data->displayType->default]++;
     }
     $checkedRegularSteps = false;
     // Display data
     foreach ($this->data as $datasetName => $data) {
         --$nr[$data->displayType->default];
         // Check which axis should be used
         $xAxis = $data->xAxis->default ? $data->xAxis->default : $this->elements['xAxis'];
         $yAxis = $data->yAxis->default ? $data->yAxis->default : $this->elements['yAxis'];
         // Determine fill color for dataset
         if ($this->options->fillLines !== false) {
             $fillColor = clone $data->color->default;
             $fillColor->alpha = (int) round((255 - $fillColor->alpha) * ($this->options->fillLines / 255));
         } else {
             $fillColor = null;
         }
         // Ensure regular steps on axis when used with bar charts and
         // precalculate some values use to render bar charts
         //
         // Called only once and only when bars should be rendered
         if ($checkedRegularSteps === false && $data->displayType->default === ezcGraph::BAR) {
             $height = $this->calculateStepWidth($yAxis, $xAxis, $boundings->height)->y;
         }
         // Draw lines for dataset
         $lastPoint = false;
         foreach ($data as $key => $value) {
             // Calculate point in chart
             $point = $xAxis->axisLabelRenderer->modifyChartDataPosition($yAxis->axisLabelRenderer->modifyChartDataPosition(new ezcGraphCoordinate($xAxis->getCoordinate($value), $yAxis->getCoordinate($key))));
             // Render depending on display type of dataset
             switch (true) {
                 case $data->displayType->default === ezcGraph::BAR:
                     $renderer->drawHorizontalBar($boundings, new ezcGraphContext($datasetName, $key, $data->url[$key]), $data->color[$key], $point, $height, $nr[$data->displayType->default], $count[$data->displayType->default], $data->symbol[$key], $yAxisNullPosition);
                     // Render highlight string if requested
                     if ($data->highlight[$key]) {
                         $renderer->drawDataHighlightText($boundings, new ezcGraphContext($datasetName, $key, $data->url[$key]), $point, $yAxisNullPosition, $nr[$data->displayType->default], $count[$data->displayType->default], $this->options->highlightFont, $data->highlightValue[$key] ? $data->highlightValue[$key] : $value, $this->options->highlightSize + $this->options->highlightFont->padding * 2, $this->options->highlightLines ? $data->color[$key] : null, $this->options->highlightXOffset ? $this->options->highlightXOffset : 0, $this->options->highlightYOffset ? $this->options->highlightYOffset : 0, $height, $data->displayType->default);
                     }
                     break;
                 default:
                     throw new ezcGraphInvalidDisplayTypeException($data->displayType->default);
                     break;
             }
             // Store last point, used to connect lines in line chart.
             $lastPoint = $point;
         }
     }
 }

 /**
  * Render a legend
  * 
  * @param ezcGraphRenderer $renderer Renderer
  * @param ezcGraphBoundings $boundings Boundings for the axis
  * @return ezcGraphBoundings Remaining boundings
  */
 public function render(ezcGraphRenderer $renderer, ezcGraphBoundings $boundings)
 {
     $boundings = $this->calculateBoundings($boundings);
     if ($this->position === ezcGraph::LEFT || $this->position === ezcGraph::RIGHT) {
         $type = ezcGraph::VERTICAL;
     } else {
         $type = ezcGraph::HORIZONTAL;
     }
     // Render standard elements
     $this->properties['boundings'] = $renderer->drawBox($this->properties['boundings'], $this->properties['background'], $this->properties['border'], $this->properties['borderWidth'], $this->properties['margin'], $this->properties['padding'], $this->properties['title'], $this->getTitleSize($this->properties['boundings'], $type));
     // Render legend
     $renderer->drawLegend($this->boundings, $this, $type);
     return $boundings;
 }

 /**
  * Draw grid
  *
  * Draws a grid line at the current position
  * 
  * @param ezcGraphRenderer $renderer Renderer to draw the grid with
  * @param ezcGraphBoundings $boundings Boundings of axis
  * @param ezcGraphCoordinate $position Position of step
  * @param ezcGraphCoordinate $direction Direction of axis
  * @param ezcGraphColor $color Color of axis
  * @return void
  */
 protected function drawGrid(ezcGraphRenderer $renderer, ezcGraphBoundings $boundings, ezcGraphCoordinate $position, ezcGraphCoordinate $direction, ezcGraphColor $color)
 {
     // Direction of grid line is direction of axis turned right by 90
     // degrees
     $gridDirection = new ezcGraphCoordinate($direction->y, -$direction->x);
     $cuttingPoints = array();
     foreach (array(array('start' => new ezcGraphCoordinate($boundings->x0, $boundings->y0), 'dir' => new ezcGraphCoordinate(0, $boundings->y1 - $boundings->y0)), array('start' => new ezcGraphCoordinate($boundings->x0, $boundings->y0), 'dir' => new ezcGraphCoordinate($boundings->x1 - $boundings->x0, 0)), array('start' => new ezcGraphCoordinate($boundings->x1, $boundings->y1), 'dir' => new ezcGraphCoordinate(0, $boundings->y0 - $boundings->y1)), array('start' => new ezcGraphCoordinate($boundings->x1, $boundings->y1), 'dir' => new ezcGraphCoordinate($boundings->x0 - $boundings->x1, 0))) as $boundingLine) {
         // Test for cutting points with bounding lines, where cutting
         // position is between 0 and 1, which means, that the line is hit
         // on the bounding box rectangle. Use these points as a start and
         // ending point for the grid lines. There should *always* be
         // exactly two points returned.
         $cuttingPosition = $this->determineLineCuttingPoint($boundingLine['start'], $boundingLine['dir'], $position, $gridDirection);
         if ($cuttingPosition === false) {
             continue;
         }
         // Round to prevent minor float incorectnesses
         $cuttingPosition = abs(round($cuttingPosition, 2));
         if ($cuttingPosition >= 0 && $cuttingPosition <= 1) {
             $cuttingPoints[] = new ezcGraphCoordinate($boundingLine['start']->x + $cuttingPosition * $boundingLine['dir']->x, $boundingLine['start']->y + $cuttingPosition * $boundingLine['dir']->y);
         }
     }
     if (count($cuttingPoints) < 2) {
         // This should not happpen
         return false;
     }
     // Finally draw grid line
     $renderer->drawGridLine($cuttingPoints[0], $cuttingPoints[1], $color);
 }

 /**
  * Render Axis labels
  *
  * Render labels for an axis.
  *
  * @param ezcGraphRenderer $renderer Renderer used to draw the chart
  * @param ezcGraphBoundings $boundings Boundings of the axis
  * @param ezcGraphCoordinate $start Axis starting point
  * @param ezcGraphCoordinate $end Axis ending point
  * @param ezcGraphChartElementAxis $axis Axis instance
  * @return void
  */
 public function renderLabels(ezcGraphRenderer $renderer, ezcGraphBoundings $boundings, ezcGraphCoordinate $start, ezcGraphCoordinate $end, ezcGraphChartElementAxis $axis)
 {
     // receive rendering parameters from axis
     $steps = $axis->getSteps();
     $this->steps = $steps;
     $axisBoundings = new ezcGraphBoundings($start->x, $start->y, $end->x, $end->y);
     // Determine normalized axis direction
     $this->direction = new ezcGraphVector($end->x - $start->x, $end->y - $start->y);
     $this->direction->unify();
     $axisAngle = -$this->direction->angle(new ezcGraphVector(1, 0));
     if ($this->outerGrid) {
         $gridBoundings = $boundings;
     } else {
         $gridBoundings = new ezcGraphBoundings($boundings->x0 + $renderer->xAxisSpace, $boundings->y0 + $renderer->yAxisSpace, $boundings->x1 - $renderer->xAxisSpace, $boundings->y1 - $renderer->yAxisSpace);
     }
     // Determine optimal angle if none specified
     if ($this->angle === null) {
         $minimumStepWidth = null;
         foreach ($steps as $nr => $step) {
             if ($minimumStepWidth === null || $step->width < $minimumStepWidth) {
                 $minimumStepWidth = $step->width;
             }
         }
         $width = abs($axisBoundings->width * $minimumStepWidth * $this->direction->x + $axisBoundings->height * $minimumStepWidth * $this->direction->y);
         $height = abs($renderer->yAxisSpace * $this->direction->x + $renderer->xAxisSpace * $this->direction->y);
         $length = sqrt(pow($width, 2) + pow($height, 2));
         $this->angle = rad2deg(acos($height / $length));
     }
     // Determine additional required axis space by boxes
     $firstStep = reset($steps);
     $lastStep = end($steps);
     $textAngle = $axisAngle + deg2rad($this->angle) + ($axis->position & (ezcGraph::TOP | ezcGraph::BOTTOM) ? deg2rad(270) : deg2rad(90));
     // Ensure angle between 0 and 360 degrees
     $degTextAngle = rad2deg($textAngle);
     while ($degTextAngle < 0) {
         $degTextAngle += 360.0;
     }
     $this->offset = ($this->angle < 0 ? -1 : 1) * ($axis->position & (ezcGraph::TOP | ezcGraph::LEFT) ? 1 : -1) * (1 - cos(deg2rad($this->angle * 2)));
     $axisSpaceFactor = abs(($this->direction->x == 0 ? 0 : $this->direction->x * $renderer->yAxisSpace / $axisBoundings->width) + ($this->direction->y == 0 ? 0 : $this->direction->y * $renderer->xAxisSpace / $axisBoundings->height));
     $start = new ezcGraphCoordinate($start->x + max(0.0, $axisSpaceFactor * $this->offset) * ($end->x - $start->x), $start->y + max(0.0, $axisSpaceFactor * $this->offset) * ($end->y - $start->y));
     $end = new ezcGraphCoordinate($end->x + min(0.0, $axisSpaceFactor * $this->offset) * ($end->x - $start->x), $end->y + min(0.0, $axisSpaceFactor * $this->offset) * ($end->y - $start->y));
     $labelLength = sqrt(pow($renderer->xAxisSpace * $this->direction->y + $axisSpaceFactor * $this->offset * ($end->x - $start->x), 2) + pow($renderer->yAxisSpace * $this->direction->x + $axisSpaceFactor * $this->offset * ($end->y - $start->y), 2));
     $this->offset *= $axisSpaceFactor;
     // Draw steps and grid
     foreach ($steps as $nr => $step) {
         $position = new ezcGraphCoordinate($start->x + ($end->x - $start->x) * $step->position * abs($this->direction->x), $start->y + ($end->y - $start->y) * $step->position * abs($this->direction->y));
         $stepSize = new ezcGraphCoordinate(($end->x - $start->x) * $step->width, ($end->y - $start->y) * $step->width);
         // Calculate label boundings
         switch (true) {
             case $nr === 0:
                 $labelSize = min(abs($renderer->xAxisSpace * 2 * $this->direction->x + $renderer->yAxisSpace * 2 * $this->direction->y), abs($step->width * $axisBoundings->width * $this->direction->x + $step->width * $axisBoundings->height * $this->direction->y));
                 break;
             case $step->isLast:
                 $labelSize = min(abs($renderer->xAxisSpace * 2 * $this->direction->x + $renderer->yAxisSpace * 2 * $this->direction->y), abs($steps[$nr - 1]->width * $axisBoundings->width * $this->direction->x + $steps[$nr - 1]->width * $axisBoundings->height * $this->direction->y));
                 break;
             default:
                 $labelSize = min(abs($step->width * $axisBoundings->width * $this->direction->x + $step->width * $axisBoundings->height * $this->direction->y), abs($steps[$nr - 1]->width * $axisBoundings->width * $this->direction->x + $steps[$nr - 1]->width * $axisBoundings->height * $this->direction->y));
                 break;
         }
         $labelSize = $labelSize * cos(deg2rad($this->angle));
         $lengthReducement = min(abs(tan(deg2rad($this->angle)) * ($labelSize / 2)), abs($labelLength / 2));
         switch (true) {
             case $degTextAngle >= 0 && $degTextAngle < 90 && ($axis->position === ezcGraph::LEFT || $axis->position === ezcGraph::RIGHT) || $degTextAngle >= 270 && $degTextAngle < 360 && ($axis->position === ezcGraph::TOP || $axis->position === ezcGraph::BOTTOM):
                 $labelBoundings = new ezcGraphBoundings($position->x, $position->y, $position->x + abs($labelLength) - $lengthReducement, $position->y + $labelSize);
                 $labelAlignement = ezcGraph::LEFT | ezcGraph::TOP;
                 $labelRotation = $degTextAngle;
                 break;
             case $degTextAngle >= 90 && $degTextAngle < 180 && ($axis->position === ezcGraph::LEFT || $axis->position === ezcGraph::RIGHT) || $degTextAngle >= 180 && $degTextAngle < 270 && ($axis->position === ezcGraph::TOP || $axis->position === ezcGraph::BOTTOM):
                 $labelBoundings = new ezcGraphBoundings($position->x - abs($labelLength) + $lengthReducement, $position->y, $position->x, $position->y + $labelSize);
                 $labelAlignement = ezcGraph::RIGHT | ezcGraph::TOP;
                 $labelRotation = $degTextAngle - 180;
                 break;
             case $degTextAngle >= 180 && $degTextAngle < 270 && ($axis->position === ezcGraph::LEFT || $axis->position === ezcGraph::RIGHT) || $degTextAngle >= 90 && $degTextAngle < 180 && ($axis->position === ezcGraph::TOP || $axis->position === ezcGraph::BOTTOM):
                 $labelBoundings = new ezcGraphBoundings($position->x - abs($labelLength) + $lengthReducement, $position->y - $labelSize, $position->x, $position->y);
                 $labelAlignement = ezcGraph::RIGHT | ezcGraph::BOTTOM;
                 $labelRotation = $degTextAngle - 180;
                 break;
             case $degTextAngle >= 270 && $degTextAngle < 360 && ($axis->position === ezcGraph::LEFT || $axis->position === ezcGraph::RIGHT) || $degTextAngle >= 0 && $degTextAngle < 90 && ($axis->position === ezcGraph::TOP || $axis->position === ezcGraph::BOTTOM):
                 $labelBoundings = new ezcGraphBoundings($position->x, $position->y + $labelSize, $position->x + abs($labelLength) - $lengthReducement, $position->y);
                 $labelAlignement = ezcGraph::LEFT | ezcGraph::BOTTOM;
                 $labelRotation = $degTextAngle;
                 break;
         }
         $renderer->drawText($labelBoundings, $step->label, $labelAlignement, new ezcGraphRotation($labelRotation, $position));
         // major grid
         if ($axis->majorGrid) {
             $this->drawGrid($renderer, $gridBoundings, $position, $stepSize, $axis->majorGrid);
         }
//.........这里部分代码省略.........

 /**
  * Draw grid
  *
  * Draws a grid line at the current position
  * 
  * @param ezcGraphRenderer $renderer Renderer to draw the grid with
  * @param ezcGraphBoundings $boundings Boundings of axis
  * @param ezcGraphCoordinate $position Position of step
  * @param ezcGraphCoordinate $direction Direction of axis
  * @param ezcGraphColor $color Color of axis
  * @param int $stepPosition
  * @return void
  */
 protected function drawGrid(ezcGraphRenderer $renderer, ezcGraphBoundings $boundings, ezcGraphCoordinate $position, ezcGraphCoordinate $direction, ezcGraphColor $color, $stepPosition = null)
 {
     // Calculate position on last axis
     $start = new ezcGraphCoordinate($boundings->x0 + ($width = $boundings->width / 2), $boundings->y0 + ($height = $boundings->height / 2));
     $lastAngle = $this->lastStep * 2 * M_PI;
     $end = new ezcGraphCoordinate($start->x + sin($lastAngle) * $width, $start->y - cos($lastAngle) * $height);
     $direction = new ezcGraphVector($end->x - $start->x, $end->y - $start->y);
     $direction->unify();
     // Convert elipse to circle for correct angle calculation
     $direction->y *= $renderer->xAxisSpace / $renderer->yAxisSpace;
     $angle = $direction->angle(new ezcGraphVector(0, 1));
     $movement = new ezcGraphVector(sin($angle) * $renderer->xAxisSpace * ($direction->x < 0 ? -1 : 1), cos($angle) * $renderer->yAxisSpace);
     $start->x += $movement->x;
     $start->y += $movement->y;
     $end->x -= $movement->x;
     $end->y -= $movement->y;
     $lastPosition = new ezcGraphCoordinate($start->x + ($end->x - $start->x) * $stepPosition, $start->y + ($end->y - $start->y) * $stepPosition);
     $renderer->drawGridLine($position, $lastPosition, $color);
 }

 /**
  * Render the axis 
  * 
  * @param ezcGraphRenderer $renderer Renderer
  * @param ezcGraphBoundings $boundings Boundings for the axis
  * @return ezcGraphBoundings Remaining boundings
  */
 public function render(ezcGraphRenderer $renderer, ezcGraphBoundings $boundings)
 {
     switch ($this->position) {
         case ezcGraph::TOP:
             $start = new ezcGraphCoordinate(($boundings->x1 - $boundings->x0) * $this->axisSpace + $this->nullPosition * ($boundings->x1 - $boundings->x0) * (1 - 2 * $this->axisSpace), 0);
             $end = new ezcGraphCoordinate(($boundings->x1 - $boundings->x0) * $this->axisSpace + $this->nullPosition * ($boundings->x1 - $boundings->x0) * (1 - 2 * $this->axisSpace), $boundings->y1 - $boundings->y0);
             break;
         case ezcGraph::BOTTOM:
             $start = new ezcGraphCoordinate(($boundings->x1 - $boundings->x0) * $this->axisSpace + $this->nullPosition * ($boundings->x1 - $boundings->x0) * (1 - 2 * $this->axisSpace), $boundings->y1 - $boundings->y0);
             $end = new ezcGraphCoordinate(($boundings->x1 - $boundings->x0) * $this->axisSpace + $this->nullPosition * ($boundings->x1 - $boundings->x0) * (1 - 2 * $this->axisSpace), 0);
             break;
         case ezcGraph::LEFT:
             $start = new ezcGraphCoordinate(0, ($boundings->y1 - $boundings->y0) * $this->axisSpace + $this->nullPosition * ($boundings->y1 - $boundings->y0) * (1 - 2 * $this->axisSpace));
             $end = new ezcGraphCoordinate($boundings->x1 - $boundings->x0, ($boundings->y1 - $boundings->y0) * $this->axisSpace + $this->nullPosition * ($boundings->y1 - $boundings->y0) * (1 - 2 * $this->axisSpace));
             break;
         case ezcGraph::RIGHT:
             $start = new ezcGraphCoordinate($boundings->x1 - $boundings->x0, ($boundings->y1 - $boundings->y0) * $this->axisSpace + $this->nullPosition * ($boundings->y1 - $boundings->y0) * (1 - 2 * $this->axisSpace));
             $end = new ezcGraphCoordinate(0, ($boundings->y1 - $boundings->y0) * $this->axisSpace + $this->nullPosition * ($boundings->y1 - $boundings->y0) * (1 - 2 * $this->axisSpace));
             break;
     }
     $renderer->drawAxis($boundings, $start, $end, $this, $this->axisLabelRenderer);
     return $boundings;
 }

 /**
  * Render label text.
  *
  * Render the text of a single label, depending on the position, length and
  * rotation of the label.
  * 
  * @param ezcGraphRenderer $renderer
  * @param ezcGraphChartElementAxis $axis 
  * @param ezcGraphCoordinate $position 
  * @param string $label 
  * @param float $degTextAngle 
  * @param float $labelLength 
  * @param float $labelSize 
  * @param float $lengthReducement 
  * @return void
  */
 protected function renderLabelText(ezcGraphRenderer $renderer, ezcGraphChartElementAxis $axis, ezcGraphCoordinate $position, $label, $degTextAngle, $labelLength, $labelSize, $lengthReducement)
 {
     switch (true) {
         case $degTextAngle >= 0 && $degTextAngle < 90 && ($axis->position === ezcGraph::LEFT || $axis->position === ezcGraph::RIGHT) || $degTextAngle >= 270 && $degTextAngle < 360 && ($axis->position === ezcGraph::TOP || $axis->position === ezcGraph::BOTTOM):
             $labelBoundings = new ezcGraphBoundings($position->x, $position->y, $position->x + abs($labelLength) - $lengthReducement, $position->y + $labelSize);
             $labelAlignement = ezcGraph::LEFT | ezcGraph::TOP;
             $labelRotation = $degTextAngle;
             break;
         case $degTextAngle >= 90 && $degTextAngle < 180 && ($axis->position === ezcGraph::LEFT || $axis->position === ezcGraph::RIGHT) || $degTextAngle >= 180 && $degTextAngle < 270 && ($axis->position === ezcGraph::TOP || $axis->position === ezcGraph::BOTTOM):
             $labelBoundings = new ezcGraphBoundings($position->x - abs($labelLength) + $lengthReducement, $position->y, $position->x, $position->y + $labelSize);
             $labelAlignement = ezcGraph::RIGHT | ezcGraph::TOP;
             $labelRotation = $degTextAngle - 180;
             break;
         case $degTextAngle >= 180 && $degTextAngle < 270 && ($axis->position === ezcGraph::LEFT || $axis->position === ezcGraph::RIGHT) || $degTextAngle >= 90 && $degTextAngle < 180 && ($axis->position === ezcGraph::TOP || $axis->position === ezcGraph::BOTTOM):
             $labelBoundings = new ezcGraphBoundings($position->x - abs($labelLength) + $lengthReducement, $position->y - $labelSize, $position->x, $position->y);
             $labelAlignement = ezcGraph::RIGHT | ezcGraph::BOTTOM;
             $labelRotation = $degTextAngle - 180;
             break;
         case $degTextAngle >= 270 && $degTextAngle < 360 && ($axis->position === ezcGraph::LEFT || $axis->position === ezcGraph::RIGHT) || $degTextAngle >= 0 && $degTextAngle < 90 && ($axis->position === ezcGraph::TOP || $axis->position === ezcGraph::BOTTOM):
             $labelBoundings = new ezcGraphBoundings($position->x, $position->y, $position->x - abs($labelLength) + $lengthReducement, $position->y + $labelSize);
             $labelAlignement = ezcGraph::LEFT | ezcGraph::TOP;
             $labelRotation = $degTextAngle;
             break;
     }
     $renderer->drawText($labelBoundings, $label, $labelAlignement, new ezcGraphRotation($labelRotation, $position));
 }

 /**
  * Render the assigned data
  *
  * Will renderer all charts data in the remaining boundings after drawing 
  * all other chart elements. The data will be rendered depending on the 
  * settings in the dataset.
  * 
  * @param ezcGraphRenderer $renderer Renderer
  * @param ezcGraphBoundings $boundings Remaining boundings
  * @return void
  */
 protected function renderData(ezcGraphRenderer $renderer, ezcGraphBoundings $boundings)
 {
     // Apply axis space
     $xAxisSpace = ($boundings->x1 - $boundings->x0) * $this->axis->axisSpace;
     $yAxisSpace = ($boundings->y1 - $boundings->y0) * $this->axis->axisSpace;
     $center = new ezcGraphCoordinate($boundings->width / 2, $boundings->height / 2);
     // We do not differentiate between display types in radar charts.
     $nr = $count = count($this->data);
     // Draw axis at major steps of virtual axis
     $steps = $this->elements['rotationAxis']->getSteps();
     $lastStepPosition = null;
     $axisColor = $this->elements['axis']->border;
     foreach ($steps as $step) {
         $this->elements['axis']->label = $step->label;
         $this->drawRotatedAxis($this->elements['axis'], $boundings, $center, $step->position, $lastStepPosition);
         $lastStepPosition = $step->position;
         if (count($step->childs)) {
             foreach ($step->childs as $childStep) {
                 $this->elements['axis']->label = null;
                 $this->elements['axis']->border = $this->childAxisColor;
                 $this->drawRotatedAxis($this->elements['axis'], $boundings, $center, $childStep->position, $lastStepPosition);
                 $lastStepPosition = $childStep->position;
             }
         }
         $this->elements['axis']->border = $axisColor;
     }
     // Display data
     $this->elements['axis']->position = ezcGraph::TOP;
     foreach ($this->data as $datasetName => $data) {
         --$nr;
         // Determine fill color for dataset
         if ($this->options->fillLines !== false) {
             $fillColor = clone $data->color->default;
             $fillColor->alpha = (int) round((255 - $fillColor->alpha) * ($this->options->fillLines / 255));
         } else {
             $fillColor = null;
         }
         // Draw lines for dataset
         $lastPoint = false;
         foreach ($data as $key => $value) {
             $point = new ezcGraphCoordinate($this->elements['rotationAxis']->getCoordinate($key), $this->elements['axis']->getCoordinate($value));
             /* Transformation required for 3d like renderers ... 
                 * which axis should transform here?
                $point = $this->elements['xAxis']->axisLabelRenderer->modifyChartDataPosition( 
                    $this->elements['yAxis']->axisLabelRenderer->modifyChartDataPosition(
                        new ezcGraphCoordinate( 
                            $this->elements['xAxis']->getCoordinate( $key ),
                            $this->elements['yAxis']->getCoordinate( $value )
                        )
                    )
                ); 
                // */
             $renderer->drawRadarDataLine($boundings, new ezcGraphContext($datasetName, $key, $data->url[$key]), $data->color->default, clone $center, $lastPoint === false ? $point : $lastPoint, $point, $nr, $count, $data->symbol[$key], $data->color[$key], $fillColor, $this->options->lineThickness);
             $lastPoint = $point;
         }
     }
 }

 /**
  * Render the assigned data
  *
  * Will renderer all charts data in the remaining boundings after drawing
  * all other chart elements. The data will be rendered depending on the
  * settings in the dataset.
  *
  * @param ezcGraphRenderer $renderer Renderer
  * @param ezcGraphBoundings $boundings Remaining boundings
  * @return void
  */
 protected function renderData(ezcGraphRenderer $renderer, ezcGraphBoundings $boundings)
 {
     // Draw the odometer data
     $dataset = $this->data->rewind();
     foreach ($dataset as $key => $value) {
         $renderer->drawOdometerMarker($boundings, $this->elements['axis']->axisLabelRenderer->modifyChartDataPosition(new ezcGraphCoordinate($this->elements['axis']->getCoordinate($value), 0)), $dataset->symbol[$key], $dataset->color[$key], $this->options->markerWidth);
     }
 }

 /**
  * Draw rectangular grid
  *
  * Draws a grid line at the current position for rectangular directed axis.
  *
  * Method special for rectangularly directed axis to minimize the floating
  * point calculation inaccuracies. Those are not necessary for rectangles,
  * while for non-rectangular directed axis.
  * 
  * @param ezcGraphRenderer $renderer Renderer to draw the grid with
  * @param ezcGraphBoundings $boundings Boundings of axis
  * @param ezcGraphCoordinate $position Position of step
  * @param ezcGraphCoordinate $direction Direction of axis
  * @param ezcGraphColor $color Color of axis
  * @return void
  */
 protected function drawRectangularGrid(ezcGraphRenderer $renderer, ezcGraphBoundings $boundings, ezcGraphCoordinate $position, ezcGraphCoordinate $direction, ezcGraphColor $color)
 {
     if (abs($direction->x) < 1.0E-5) {
         $renderer->drawGridLine(new ezcGraphCoordinate($boundings->x0, $position->y), new ezcGraphCoordinate($boundings->x1, $position->y), $color);
     } else {
         $renderer->drawGridLine(new ezcGraphCoordinate($position->x, $boundings->y0), new ezcGraphCoordinate($position->x, $boundings->y1), $color);
     }
 }

 /**
  * Render the axis 
  * 
  * @param ezcGraphRenderer $renderer Renderer
  * @param ezcGraphBoundings $boundings Boundings for the axis
  * @return ezcGraphBoundings Remaining boundings
  */
 public function render(ezcGraphRenderer $renderer, ezcGraphBoundings $boundings, ezcGraphBoundings $innerBoundings = null)
 {
     $this->innerBoundings = $innerBoundings;
     $startSpace = $this->axisSpace;
     $endSpace = $this->outerAxisSpace === null ? $this->axisSpace : $this->outerAxisSpace;
     switch ($this->position) {
         case ezcGraph::TOP:
             $start = new ezcGraphCoordinate($boundings->width * $startSpace + $this->nullPosition * $boundings->width * (1 - ($startSpace + $endSpace)), 0);
             $end = new ezcGraphCoordinate($boundings->width * $startSpace + $this->nullPosition * $boundings->width * (1 - ($startSpace + $endSpace)), $boundings->height);
             break;
         case ezcGraph::BOTTOM:
             $start = new ezcGraphCoordinate($boundings->width * $startSpace + $this->nullPosition * $boundings->width * (1 - ($startSpace + $endSpace)), $boundings->height);
             $end = new ezcGraphCoordinate($boundings->width * $startSpace + $this->nullPosition * $boundings->width * (1 - ($startSpace + $endSpace)), 0);
             break;
         case ezcGraph::LEFT:
             $start = new ezcGraphCoordinate(0, $boundings->height * $endSpace + $this->nullPosition * $boundings->height * (1 - ($startSpace + $endSpace)));
             $end = new ezcGraphCoordinate($boundings->width, $boundings->height * $endSpace + $this->nullPosition * $boundings->height * (1 - ($startSpace + $endSpace)));
             break;
         case ezcGraph::RIGHT:
             $start = new ezcGraphCoordinate($boundings->width, $boundings->height * $endSpace + $this->nullPosition * $boundings->height * (1 - ($startSpace + $endSpace)));
             $end = new ezcGraphCoordinate(0, $boundings->height * $endSpace + $this->nullPosition * $boundings->height * (1 - ($startSpace + $endSpace)));
             break;
     }
     $renderer->drawAxis($boundings, $start, $end, $this, $this->axisLabelRenderer, $innerBoundings);
     return $boundings;
 }

 /**
  * Render the assigned data
  *
  * Will renderer all charts data in the remaining boundings after drawing 
  * all other chart elements. The data will be rendered depending on the 
  * settings in the dataset.
  * 
  * @param ezcGraphRenderer $renderer Renderer
  * @param ezcGraphBoundings $boundings Remaining boundings
  * @return void
  */
 protected function renderData(ezcGraphRenderer $renderer, ezcGraphBoundings $boundings, ezcGraphBoundings $innerBoundings)
 {
     // Use inner boundings for drawning chart data
     $boundings = $innerBoundings;
     $yAxisNullPosition = $this->elements['yAxis']->getCoordinate(false);
     // Initialize counters
     $nr = array();
     $count = array();
     foreach ($this->data as $data) {
         if (!isset($nr[$data->displayType->default])) {
             $nr[$data->displayType->default] = 0;
             $count[$data->displayType->default] = 0;
         }
         $nr[$data->displayType->default]++;
         $count[$data->displayType->default]++;
     }
     $checkedRegularSteps = false;