/jpgraph/src/jpgraph_pie3d.php

<?php
/*=======================================================================
// File:	JPGRAPH_PIE3D.PHP
// Description: 3D Pie plot extension for JpGraph
// Created: 	2001-03-24
// Author:	Johan Persson (johanp@aditus.nu)
// Ver:		$Id: jpgraph_pie3d.php,v 1.46.2.5 2004/06/19 12:22:04 aditus Exp $
//
// License:	This code is released under QPL
// Copyright (C) 2001,2002 Johan Persson
//========================================================================
*/

//===================================================
// CLASS PiePlot3D
// Description: Plots a 3D pie with a specified projection 
// angle between 20 and 70 degrees.
//===================================================
class PiePlot3D extends PiePlot {
    public $labelhintcolor="red",$showlabelhint=true;
    public $angle=50;	
    public $edgecolor="", $edgeweight=1;
    public $iThickness=false;
	
//---------------
// CONSTRUCTOR
    function PiePlot3d(&$data) {
	$this->radius = 0.5;
	$this->data = $data;
	$this->title = new Text("");
	$this->title->SetFont(FF_FONT1,FS_BOLD);
	$this->value = new DisplayValue();
	$this->value->Show();
	$this->value->SetFormat('%.0f%%');
    }

//---------------
// PUBLIC METHODS	
	
    // Set label arrays
    function SetLegends($aLegend) {
	$this->legends = array_reverse($aLegend);
    }

    function SetSliceColors($aColors) {
	$this->setslicecolors = $aColors;
    }

    function Legend(&$aGraph) {
	parent::Legend($aGraph);
	$aGraph->legend->txtcol = array_reverse($aGraph->legend->txtcol);
    }

    function SetCSIMTargets($targets,$alts=null) {
	$this->csimtargets = $targets;
	$this->csimalts = $alts;
    }

    // Should the slices be separated by a line? If color is specified as "" no line
    // will be used to separate pie slices.
    function SetEdge($aColor,$aWeight=1) {
	$this->edgecolor = $aColor;
	$this->edgeweight = $aWeight;
    }

    // Specify projection angle for 3D in degrees
    // Must be between 20 and 70 degrees
    function SetAngle($a) {
	if( $a<5 || $a>90 )
	    JpGraphError::Raise("PiePlot3D::SetAngle() 3D Pie projection angle must be between 5 and 85 degrees.");
	else
	    $this->angle = $a;
    }

    function AddSliceToCSIM($i,$xc,$yc,$height,$width,$thick,$sa,$ea) {  //Slice number, ellipse centre (x,y), height, width, start angle, end angle

	$sa *= M_PI/180;
	$ea *= M_PI/180;

	//add coordinates of the centre to the map
	$coords = "$xc, $yc";

	//add coordinates of the first point on the arc to the map
	$xp = floor($width*cos($sa)/2+$xc);
	$yp = floor($yc-$height*sin($sa)/2);
	$coords.= ", $xp, $yp";

	//If on the front half, add the thickness offset
	if ($sa >= M_PI && $sa <= 2*M_PI*1.01) {
	    $yp = floor($yp+$thick);
	    $coords.= ", $xp, $yp";
	}
		
	//add coordinates every 0.2 radians
	$a=$sa+0.2;
	while ($a<$ea) {
	    $xp = floor($width*cos($a)/2+$xc);
	    if ($a >= M_PI && $a <= 2*M_PI*1.01) {
		$yp = floor($yc-($height*sin($a)/2)+$thick);
	    } else {
		$yp = floor($yc-$height*sin($a)/2);
	    }
	    $coords.= ", $xp, $yp";
	    $a += 0.2;
	}
		
	//Add the last point on the arc
	$xp = floor($width*cos($ea)/2+$xc);
	$yp = floor($yc-$height*sin($ea)/2);


	if ($ea >= M_PI && $ea <= 2*M_PI*1.01) {
	    $coords.= ", $xp, ".floor($yp+$thick);
	}
	$coords.= ", $xp, $yp";
	$alt='';
	if( !empty($this->csimalts[$i]) ) {										
	    $tmp=sprintf($this->csimalts[$i],$this->data[$i]);
	    $alt="alt=\"$tmp\" title=\"$tmp\"";
	}
	if( !empty($this->csimtargets[$i]) )
	    $this->csimareas .= "<area shape=\"poly\" coords=\"$coords\" href=\"".$this->csimtargets[$i]."\" $alt>\n";
    }

    function SetLabels($aLabels,$aLblPosAdj="auto") {
	$this->labels = $aLabels;
	$this->ilabelposadj=$aLblPosAdj;
    }

	
    // Distance from the pie to the labels
    function SetLabelMargin($m) {
	$this->value->SetMargin($m);
    }
	
    // Show a thin line from the pie to the label for a specific slice
    function ShowLabelHint($f=true) {
	$this->showlabelhint=$f;
    }
	
    // Set color of hint line to label for each slice
    function SetLabelHintColor($c) {
	$this->labelhintcolor=$c;
    }

    function SetHeight($aHeight) {
      $this->iThickness = $aHeight;
    }


// Normalize Angle between 0-360
    function NormAngle($a) {
	// Normalize anle to 0 to 2M_PI
	// 
	if( $a > 0 ) {
	    while($a > 360) $a -= 360;
	}
	else {
	    while($a < 0) $a += 360;
	}
	if( $a < 0 )
	    $a = 360 + $a;

	if( $a == 360 ) $a=0;
	return $a;
    }

    

// Draw one 3D pie slice at position ($xc,$yc) with height $z
    function Pie3DSlice($img,$xc,$yc,$w,$h,$sa,$ea,$z,$fillcolor,$shadow=0.65) {
	
	// Due to the way the 3D Pie algorithm works we are
	// guaranteed that any slice we get into this method
	// belongs to either the left or right side of the
	// pie ellipse. Hence, no slice will cross 90 or 270
	// point.
	if( ($sa < 90 && $ea > 90) || ( ($sa > 90 && $sa < 270) && $ea > 270) ) {
	    JpGraphError::Raise('Internal assertion failed. Pie3D::Pie3DSlice');
	    exit(1);
	}

	$p[] = array();

	// Setup pre-calculated values
	$rsa = $sa/180*M_PI;	// to Rad
	$rea = $ea/180*M_PI;	// to Rad
	$sinsa = sin($rsa);
	$cossa = cos($rsa);
	$sinea = sin($rea);
	$cosea = cos($rea);

	// p[] is the points for the overall slice and
	// pt[] is the points for the top pie

	// Angular step when approximating the arc with a polygon train.
	$step = 0.05;

	if( $sa >= 270 ) {
	    if( $ea > 360 || ($ea > 0 && $ea <= 90) ) {
		if( $ea > 0 && $ea <= 90 ) {
		    // Adjust angle to simplify conditions in loops
		    $rea += 2*M_PI;
		}

		$p = array($xc,$yc,$xc,$yc+$z,
			   $xc+$w*$cossa,$z+$yc-$h*$sinsa);
		$pt = array($xc,$yc,$xc+$w*$cossa,$yc-$h*$sinsa);

		for( $a=$rsa; $a < 2*M_PI; $a += $step ) {
		    $tca = cos($a);
		    $tsa = sin($a);
		    $p[] = $xc+$w*$tca;
		    $p[] = $z+$yc-$h*$tsa;
		    $pt[] = $xc+$w*$tca;
		    $pt[] = $yc-$h*$tsa;
		}

		$pt[] = $xc+$w;
		$pt[] = $yc;

		$p[] = $xc+$w;
		$p[] = $z+$yc;
		$p[] = $xc+$w;
		$p[] = $yc;
		$p[] = $xc;
		$p[] = $yc;

		for( $a=2*M_PI+$step; $a < $rea; $a += $step ) {
		    $pt[] = $xc + $w*cos($a);
		    $pt[] = $yc - $h*sin($a);
		}
		    
		$pt[] = $xc+$w*$cosea;
		$pt[] = $yc-$h*$sinea;
		$pt[] = $xc;
		$pt[] = $yc;

	    }
	    else {
		$p = array($xc,$yc,$xc,$yc+$z,
			   $xc+$w*$cossa,$z+$yc-$h*$sinsa);
		$pt = array($xc,$yc,$xc+$w*$cossa,$yc-$h*$sinsa);
		    
		$rea = $rea == 0.0 ? 2*M_PI : $rea;
		for( $a=$rsa; $a < $rea; $a += $step ) {
		    $tca = cos($a);
		    $tsa = sin($a);
		    $p[] = $xc+$w*$tca;
		    $p[] = $z+$yc-$h*$tsa;
		    $pt[] = $xc+$w*$tca;
		    $pt[] = $yc-$h*$tsa;
		}

		$pt[] = $xc+$w*$cosea;
		$pt[] = $yc-$h*$sinea;
		$pt[] = $xc;
		$pt[] = $yc;
		    
		$p[] = $xc+$w*$cosea;
		$p[] = $z+$yc-$h*$sinea;
		$p[] = $xc+$w*$cosea;
		$p[] = $yc-$h*$sinea;
		$p[] = $xc;
		$p[] = $yc;
	    }
	}
	elseif( $sa >= 180 ) {
	    $p = array($xc,$yc,$xc,$yc+$z,$xc+$w*$cosea,$z+$yc-$h*$sinea);
	    $pt = array($xc,$yc,$xc+$w*$cosea,$yc-$h*$sinea);
		
	    for( $a=$rea; $a>$rsa; $a -= $step ) {
		$tca = cos($a);
		$tsa = sin($a);
		$p[] = $xc+$w*$tca;
		$p[] = $z+$yc-$h*$tsa;
		$pt[] = $xc+$w*$tca;
		$pt[] = $yc-$h*$tsa;
	    }

	    $pt[] = $xc+$w*$cossa;
	    $pt[] = $yc-$h*$sinsa;
	    $pt[] = $xc;
	    $pt[] = $yc;
		
	    $p[] = $xc+$w*$cossa;
	    $p[] = $z+$yc-$h*$sinsa;
	    $p[] = $xc+$w*$cossa;
	    $p[] = $yc-$h*$sinsa;
	    $p[] = $xc;
	    $p[] = $yc;
	
	}
	elseif( $sa >= 90 ) {
	    if( $ea > 180 ) {
		$p = array($xc,$yc,$xc,$yc+$z,$xc+$w*$cosea,$z+$yc-$h*$sinea);
		$pt = array($xc,$yc,$xc+$w*$cosea,$yc-$h*$sinea);

		for( $a=$rea; $a > M_PI; $a -= $step ) {
		    $tca = cos($a);
		    $tsa = sin($a);		    
		    $p[] = $xc+$w*$tca;
		    $p[] = $z + $yc - $h*$tsa;
		    $pt[] = $xc+$w*$tca;
		    $pt[] = $yc-$h*$tsa;
		}

		$p[] = $xc-$w;
		$p[] = $z+$yc;
		$p[] = $xc-$w;
		$p[] = $yc;
		$p[] = $xc;
		$p[] = $yc;

		$pt[] = $xc-$w;
		$pt[] = $z+$yc;
		$pt[] = $xc-$w;
		$pt[] = $yc;

		for( $a=M_PI-$step; $a > $rsa; $a -= $step ) {
		    $pt[] = $xc + $w*cos($a);
		    $pt[] = $yc - $h*sin($a);
		}

		$pt[] = $xc+$w*$cossa;
		$pt[] = $yc-$h*$sinsa;
		$pt[] = $xc;
		$pt[] = $yc;

	    }
	    else { // $sa >= 90 && $ea <= 180
		$p = array($xc,$yc,$xc,$yc+$z,
			   $xc+$w*$cosea,$z+$yc-$h*$sinea,
			   $xc+$w*$cosea,$yc-$h*$sinea,
			   $xc,$yc);

		$pt = array($xc,$yc,$xc+$w*$cosea,$yc-$h*$sinea);

		for( $a=$rea; $a>$rsa; $a -= $step ) {
		    $pt[] = $xc + $w*cos($a);
		    $pt[] = $yc - $h*sin($a);
		}

		$pt[] = $xc+$w*$cossa;
		$pt[] = $yc-$h*$sinsa;
		$pt[] = $xc;
		$pt[] = $yc;

	    }
	}
	else { // sa > 0 && ea < 90

	    $p = array($xc,$yc,$xc,$yc+$z,
		       $xc+$w*$cossa,$z+$yc-$h*$sinsa,
		       $xc+$w*$cossa,$yc-$h*$sinsa,
		       $xc,$yc);

	    $pt = array($xc,$yc,$xc+$w*$cossa,$yc-$h*$sinsa);

	    for( $a=$rsa; $a < $rea; $a += $step ) {
		$pt[] = $xc + $w*cos($a);
		$pt[] = $yc - $h*sin($a);
	    }

	    $pt[] = $xc+$w*$cosea;
	    $pt[] = $yc-$h*$sinea;
	    $pt[] = $xc;
	    $pt[] = $yc;
	}
	    
	$img->PushColor($fillcolor.":".$shadow);
	$img->FilledPolygon($p);
	$img->PopColor();

	$img->PushColor($fillcolor);
	$img->FilledPolygon($pt);
	$img->PopColor();
    }

    function SetStartAngle($aStart) {
	if( $aStart < 0 || $aStart > 360 ) {
	    JpGraphError::Raise('Slice start angle must be between 0 and 360 degrees.');
	}
	$this->startangle = $aStart;
    }
    
// Draw a 3D Pie
    function Pie3D($aaoption,$img,$data,$colors,$xc,$yc,$d,$angle,$z,
		   $shadow=0.65,$startangle=0,$edgecolor="",$edgeweight=1) {

	//---------------------------------------------------------------------------
	// As usual the algorithm get more complicated than I originally
	// envisioned. I believe that this is as simple as it is possible
	// to do it with the features I want. It's a good exercise to start
	// thinking on how to do this to convince your self that all this
	// is really needed for the general case.
	//
	// The algorithm two draw 3D pies without "real 3D" is done in
	// two steps.
	// First imagine the pie cut in half through a thought line between
	// 12'a clock and 6'a clock. It now easy to imagine that we can plot 
	// the individual slices for each half by starting with the topmost
	// pie slice and continue down to 6'a clock.
	// 
	// In the algortithm this is done in three principal steps
	// Step 1. Do the knife cut to ensure by splitting slices that extends 
	// over the cut line. This is done by splitting the original slices into
	// upto 3 subslices.
	// Step 2. Find the top slice for each half
	// Step 3. Draw the slices from top to bottom
	//
	// The thing that slightly complicates this scheme with all the
	// angle comparisons below is that we can have an arbitrary start
	// angle so we must take into account the different equivalence classes.
	// For the same reason we must walk through the angle array in a 
	// modulo fashion.
	//
	// Limitations of algorithm: 
	// * A small exploded slice which crosses the 270 degree point
	//   will get slightly nagged close to the center due to the fact that
	//   we print the slices in Z-order and that the slice left part
	//   get printed first and might get slightly nagged by a larger
	//   slice on the right side just before the right part of the small
	//   slice. Not a major problem though. 
	//---------------------------------------------------------------------------

    
	// Determine the height of the ellippse which gives an
	// indication of the inclination angle
	$h = ($angle/90.0)*$d;
	$sum = 0;
	for($i=0; $i<count($data); ++$i ) {
	    $sum += $data[$i];
	}
	
	// Special optimization
	if( $sum==0 ) return;

	if( $this->labeltype == 2 ) {
	    $this->adjusted_data = $this->AdjPercentage($data);
	}

	// Setup the start
	$accsum = 0;
	$a = $startangle;
	$a = $this->NormAngle($a);

	// 
	// Step 1 . Split all slices that crosses 90 or 270
	//
	$idx=0;
	$adjexplode=array(); 
	$numcolors = count($colors);
	for($i=0; $i<count($data); ++$i, ++$idx ) {
	    $da = $data[$i]/$sum * 360;

	    if( empty($this->explode_radius[$i]) )
		$this->explode_radius[$i]=0;

	    $expscale=1;
	    if( $aaoption == 1 ) 
		$expscale=2;

	    $la = $a + $da/2;
	    $explode = array( $xc + $this->explode_radius[$i]*cos($la*M_PI/180)*$expscale,
		              $yc - $this->explode_radius[$i]*sin($la*M_PI/180) * ($h/$d) *$expscale );
	    $adjexplode[$idx] = $explode;
	    $labeldata[$i] = array($la,$explode[0],$explode[1]);
	    $originalangles[$i] = array($a,$a+$da);

	    $ne = $this->NormAngle($a+$da);
	    if( $da <= 180 ) {
		// If the slice size is <= 90 it can at maximum cut across
		// one boundary (either 90 or 270) where it needs to be split
		$split=-1; // no split
		if( ($da<=90 && ($a <= 90 && $ne > 90)) ||
		    (($da <= 180 && $da >90)  && (($a < 90 || $a >= 270) && $ne > 90)) ) {
		    $split = 90;
		}
		elseif( ($da<=90 && ($a <= 270 && $ne > 270)) ||
		        (($da<=180 && $da>90) && ($a >= 90 && $a < 270 && ($a+$da) > 270 )) ) {
		    $split = 270;
		} 
		if( $split > 0 ) { // split in two
		    $angles[$idx] = array($a,$split);
		    $adjcolors[$idx] = $colors[$i % $numcolors];
		    $adjexplode[$idx] = $explode;
		    $angles[++$idx] = array($split,$ne);
		    $adjcolors[$idx] = $colors[$i % $numcolors];
		    $adjexplode[$idx] = $explode;
		}
		else { // no split
		    $angles[$idx] = array($a,$ne);
		    $adjcolors[$idx] = $colors[$i  % $numcolors];
		    $adjexplode[$idx] = $explode;	
		}
	    }
	    else { 
		// da>180
		// Slice may, depending on position, cross one or two
		// bonudaries

		if( $a < 90 ) 
		    $split = 90;
		elseif( $a <= 270 )
		    $split = 270;
		else 
		    $split = 90;

		$angles[$idx] = array($a,$split);
		$adjcolors[$idx] = $colors[$i % $numcolors];
		$adjexplode[$idx] = $explode;
		//if( $a+$da > 360-$split ) { 
		// For slices larger than 270 degrees we might cross
		// another boundary as well. This means that we must
		// split the slice further. The comparison gets a little
		// bit complicated since we must take into accound that
		// a pie might have a startangle >0 and hence a slice might
		// wrap around the 0 angle.
		// Three cases:
		//  a) Slice starts before 90 and hence gets a split=90, but 
		//     we must also check if we need to split at 270
		//  b) Slice starts after 90 but before 270 and slices
		//     crosses 90 (after a wrap around of 0)
		//  c) If start is > 270 (hence the firstr split is at 90)
		//     and the slice is so large that it goes all the way
		//     around 270.
		if( ($a < 90 && ($a+$da > 270)) ||
		    ($a > 90 && $a<=270 && ($a+$da>360+90) ) ||
		    ($a > 270 && $this->NormAngle($a+$da)>270) ) { 
		    $angles[++$idx] = array($split,360-$split);
		    $adjcolors[$idx] = $colors[$i % $numcolors];
		    $adjexplode[$idx] = $explode;
		    $angles[++$idx] = array(360-$split,$ne);
		    $adjcolors[$idx] = $colors[$i % $numcolors];
		    $adjexplode[$idx] = $explode;
		}	
		else {
		    // Just a simple split to the previous decided
		    // angle.
		    $angles[++$idx] = array($split,$ne);
		    $adjcolors[$idx] = $colors[$i % $numcolors];
		    $adjexplode[$idx] = $explode;
		}
	    }
	    $a += $da;
	    $a = $this->NormAngle($a);
	}

	// Total number of slices 
	$n = count($angles);

	for($i=0; $i<$n; ++$i) {
	    list($dbgs,$dbge) = $angles[$i];
	}

	// 
	// Step 2. Find start index (first pie that starts in upper left quadrant)
	//
	$minval = $angles[0][0];
	$min = 0;
	for( $i=0; $i<$n; ++$i ) {
	    if( $angles[$i][0] < $minval ) {
		$minval = $angles[$i][0];
		$min = $i;
	    }
	}
	$j = $min;
	$cnt = 0;
	while( $angles[$j][1] <= 90 ) {
	    $j++;
	    if( $j>=$n) {
		$j=0;
	    }
	    if( $cnt > $n ) {
		JpGraphError::Raise("Pie3D Internal error (#1). Trying to wrap twice when looking for start index");
	    }
	    ++$cnt;
	}
	$start = $j;

	// 
	// Step 3. Print slices in z-order
	//
	$cnt = 0;
	
	// First stroke all the slices between 90 and 270 (left half circle)
	// counterclockwise
	    
	while( $angles[$j][0] < 270  && $aaoption !== 2 ) {

	    list($x,$y) = $adjexplode[$j];

	    $this->Pie3DSlice($img,$x,$y,$d,$h,$angles[$j][0],$angles[$j][1],
			      $z,$adjcolors[$j],$shadow);
	
	    $last = array($x,$y,$j);

	    $j++;
	    if( $j >= $n ) $j=0;
	    if( $cnt > $n ) {
		JpGraphError::Raise("Pie3D Internal Error: Z-Sorting algorithm for 3D Pies is not working properly (2). Trying to wrap twice while stroking.");
	    }
	    ++$cnt;
	}
     
	$slice_left = $n-$cnt;
	$j=$start-1;
	if($j<0) $j=$n-1;
	$cnt = 0;
	
	// The stroke all slices from 90 to -90 (right half circle)
	// clockwise
	while( $cnt < $slice_left  && $aaoption !== 2 ) {

	    list($x,$y) = $adjexplode[$j];

	    $this->Pie3DSlice($img,$x,$y,$d,$h,$angles[$j][0],$angles[$j][1],
			      $z,$adjcolors[$j],$shadow);
	    $j--;
	    if( $cnt > $n ) {
		JpGraphError::Raise("Pie3D Internal Error: Z-Sorting algorithm for 3D Pies is not working properly (2). Trying to wrap twice while stroking.");
	    }
	    if($j<0) $j=$n-1;
	    $cnt++;
	}
	
	// Now do a special thing. Stroke the last slice on the left
	// halfcircle one more time.  This is needed in the case where 
	// the slice close to 270 have been exploded. In that case the
	// part of the slice close to the center of the pie might be 
	// slightly nagged.
	if( $aaoption !== 2 )
	    $this->Pie3DSlice($img,$last[0],$last[1],$d,$h,$angles[$last[2]][0],
			      $angles[$last[2]][1],$z,$adjcolors[$last[2]],$shadow);


	if( $aaoption !== 1 ) {
	    // Now print possible labels and add csim
	    $img->SetFont($this->value->ff,$this->value->fs);
	    $margin = $img->GetFontHeight()/2 + $this->value->margin ;
	    for($i=0; $i < count($data); ++$i ) {
		$la = $labeldata[$i][0];
		$x = $labeldata[$i][1] + cos($la*M_PI/180)*($d+$margin);
		$y = $labeldata[$i][2] - sin($la*M_PI/180)*($h+$margin);
		if( $la > 180 && $la < 360 ) $y += $z;
		if( $this->labeltype == 0 ) {
		    if( $sum > 0 )
			$l = 100*$data[$i]/$sum;
		    else
			$l = 0;
		}
		elseif( $this->labeltype == 1 ) {
		    $l = $data[$i];
		}
		else {
		    $l = $this->adjusted_data[$i];
		}
		if( isset($this->labels[$i]) && is_string($this->labels[$i]) )
		    $l=sprintf($this->labels[$i],$l);

		$this->StrokeLabels($l,$img,$labeldata[$i][0]*M_PI/180,$x,$y,$z);
	    
		$this->AddSliceToCSIM($i,$labeldata[$i][1],$labeldata[$i][2],$h*2,$d*2,$z,
				      $originalangles[$i][0],$originalangles[$i][1]);
	    }	
	}

	// 
	// Finally add potential lines in pie
	//

	if( $edgecolor=="" || $aaoption !== 0 ) return;

	$accsum = 0;
	$a = $startangle;
	$a = $this->NormAngle($a);

	$a *= M_PI/180.0;

	$idx=0;
	$img->PushColor($edgecolor);
	$img->SetLineWeight($edgeweight);
	
	$fulledge = true;
	for($i=0; $i < count($data) && $fulledge; ++$i ) {
	    if( empty($this->explode_radius[$i]) )
		$this->explode_radius[$i]=0;
	    if( $this->explode_radius[$i] > 0 ) {
		$fulledge = false;
	    }
	}
	    

	for($i=0; $i < count($data); ++$i, ++$idx ) {

	    $da = $data[$i]/$sum * 2*M_PI;
	    $this->StrokeFullSliceFrame($img,$xc,$yc,$a,$a+$da,$d,$h,$z,$edgecolor,
					$this->explode_radius[$i],$fulledge);
	    $a += $da;
	}
	$img->PopColor();
    }

    function StrokeFullSliceFrame($img,$xc,$yc,$sa,$ea,$w,$h,$z,$edgecolor,$exploderadius,$fulledge) {
	$step = 0.02;

	if( $exploderadius > 0 ) {
	    $la = ($sa+$ea)/2;
	    $xc += $exploderadius*cos($la);
	    $yc -= $exploderadius*sin($la) * ($h/$w) ;
	    
	}

	$p = array($xc,$yc,$xc+$w*cos($sa),$yc-$h*sin($sa));

	for($a=$sa; $a < $ea; $a += $step ) {
	    $p[] = $xc + $w*cos($a);
	    $p[] = $yc - $h*sin($a);
	}

	$p[] = $xc+$w*cos($ea);
	$p[] = $yc-$h*sin($ea);
	$p[] = $xc;
	$p[] = $yc;

	$img->SetColor($edgecolor);
	$img->Polygon($p);

	// Unfortunately we can't really draw the full edge around the whole of
	// of the slice if any of the slices are exploded. The reason is that
	// this algorithm is to simply. There are cases where the edges will
	// "overwrite" other slices when they have been exploded.
	// Doing the full, proper 3D hidden lines stiff is actually quite
	// tricky. So for exploded pies we only draw the top edge. Not perfect
	// but the "real" solution is much more complicated.
	if( $fulledge && !( $sa > 0 && $sa < M_PI && $ea < M_PI) ) { 

	    if($sa < M_PI && $ea > M_PI) 
		$sa = M_PI;
 
	    if($sa < 2*M_PI && (($ea >= 2*M_PI) || ($ea > 0 && $ea < $sa ) ) )
		$ea = 2*M_PI;

	    if( $sa >= M_PI && $ea <= 2*M_PI ) {
		$p = array($xc + $w*cos($sa),$yc - $h*sin($sa),
			   $xc + $w*cos($sa),$z + $yc - $h*sin($sa));
		
		for($a=$sa+$step; $a < $ea; $a += $step ) {
		    $p[] = $xc + $w*cos($a);
		    $p[] = $z + $yc - $h*sin($a);
		}
		$p[] = $xc + $w*cos($ea);
		$p[] = $z + $yc - $h*sin($ea);
		$p[] = $xc + $w*cos($ea);
		$p[] = $yc - $h*sin($ea);
		$img->SetColor($edgecolor);
		$img->Polygon($p);	    
	    }
	}
    }

    function Stroke($img,$aaoption=0) {
	$n = count($this->data);

	// If user hasn't set the colors use the theme array
   	if( $this->setslicecolors==null ) {
	    $colors = array_keys($img->rgb->rgb_table);
	    sort($colors);	
	    $idx_a=$this->themearr[$this->theme];	
	    $ca = array();
	    $m = count($idx_a);
	    for($i=0; $i < $m; ++$i)
		$ca[$i] = $colors[$idx_a[$i]];
	    $ca = array_reverse(array_slice($ca,0,$n));
	}
   	else {
	    $ca = $this->setslicecolors;
	}
	

	if( $this->posx <= 1 && $this->posx > 0 )
	    $xc = round($this->posx*$img->width);
	else
	    $xc = $this->posx ;
	
	if( $this->posy <= 1 && $this->posy > 0 )
	    $yc = round($this->posy*$img->height);
	else
	    $yc = $this->posy ;
   			
	if( $this->radius <= 1 ) {
	    $width = floor($this->radius*min($img->width,$img->height));
	    // Make sure that the pie doesn't overflow the image border
	    // The 0.9 factor is simply an extra margin to leave some space
	    // between the pie an the border of the image.
	    $width = min($width,min($xc*0.9,($yc*90/$this->angle-$width/4)*0.9));
	}
	else {
	    $width = $this->radius * ($aaoption === 1 ? 2 : 1 ) ;
	}

	// Add a sanity check for width
	if( $width < 1 ) { 
	    JpGraphError::Raise("Width for 3D Pie is 0. Specify a size > 0");
	    exit();
	}

	// Establish a thickness. By default the thickness is a fifth of the
	// pie slice width (=pie radius) but since the perspective depends
	// on the inclination angle we use some heuristics to make the edge
	// slightly thicker the less the angle.
	
	// Has user specified an absolute thickness? In that case use
	// that instead

	if( $this->iThickness ) {
	  $thick = $this->iThickness;
	  $thick *= ($aaoption === 1 ? 2 : 1 );
	}
	else
	  $thick = $width/12;
	$a = $this->angle;
	if( $a <= 30 ) $thick *= 1.6;
	elseif( $a <= 40 ) $thick *= 1.4;
	elseif( $a <= 50 ) $thick *= 1.2;
	elseif( $a <= 60 ) $thick *= 1.0;
	elseif( $a <= 70 ) $thick *= 0.8;
	elseif( $a <= 80 ) $thick *= 0.7;
	else $thick *= 0.6;

	$thick = floor($thick);

	if( $this->explode_all )
	    for($i=0; $i < $n; ++$i)
		$this->explode_radius[$i]=$this->explode_r;

	$this->Pie3D($aaoption,$img,$this->data, $ca, $xc, $yc, $width, $this->angle, 
	             $thick, 0.65, $this->startangle, $this->edgecolor, $this->edgeweight);

	// Adjust title position
	if( $aaoption != 1 ) {
	    $this->title->Pos($xc,$yc-$this->title->GetFontHeight($img)-$width/2-$this->title->margin,			      "center","bottom");
	    $this->title->Stroke($img);
	}
    }

//---------------
// PRIVATE METHODS	

    // Position the labels of each slice
    function StrokeLabels($label,$img,$a,$xp,$yp,$z) {
	$this->value->halign="left";
	$this->value->valign="top";

	// Position the axis title. 
	// dx, dy is the offset from the top left corner of the bounding box that sorrounds the text
	// that intersects with the extension of the corresponding axis. The code looks a little
	// bit messy but this is really the only way of having a reasonable position of the
	// axis titles.
	$img->SetFont($this->value->ff,$this->value->fs,$this->value->fsize);
	$h=$img->GetTextHeight($label);
	// For numeric values the format of the display value
	// must be taken into account
	if( is_numeric($label) ) {
	    if( $label >= 0 )
		$w=$img->GetTextWidth(sprintf($this->value->format,$label));
	    else
		$w=$img->GetTextWidth(sprintf($this->value->negformat,$label));
	}
	else
	    $w=$img->GetTextWidth($label);
	while( $a > 2*M_PI ) $a -= 2*M_PI;
	if( $a>=7*M_PI/4 || $a <= M_PI/4 ) $dx=0;
	if( $a>=M_PI/4 && $a <= 3*M_PI/4 ) $dx=($a-M_PI/4)*2/M_PI; 
	if( $a>=3*M_PI/4 && $a <= 5*M_PI/4 ) $dx=1;
	if( $a>=5*M_PI/4 && $a <= 7*M_PI/4 ) $dx=(1-($a-M_PI*5/4)*2/M_PI);
		
	if( $a>=7*M_PI/4 ) $dy=(($a-M_PI)-3*M_PI/4)*2/M_PI;
	if( $a<=M_PI/4 ) $dy=(1-$a*2/M_PI);
	if( $a>=M_PI/4 && $a <= 3*M_PI/4 ) $dy=1;
	if( $a>=3*M_PI/4 && $a <= 5*M_PI/4 ) $dy=(1-($a-3*M_PI/4)*2/M_PI);
	if( $a>=5*M_PI/4 && $a <= 7*M_PI/4 ) $dy=0;
	
	$x = round($xp-$dx*$w);
	$y = round($yp-$dy*$h);

	
        // Mark anchor point for debugging 
	/*
	$img->SetColor('red');
	$img->Line($xp-10,$yp,$xp+10,$yp);
	$img->Line($xp,$yp-10,$xp,$yp+10);
	*/
	$oldmargin = $this->value->margin;
	$this->value->margin=0;
	$this->value->Stroke($img,$label,$x,$y);
	$this->value->margin=$oldmargin;

    }	
} // Class

/* EOF */
?>