<?php/*=======================================================================// File:	JPGRAPH_GRADIENT.PHP// Description:	Create a color gradient// Created: 	2003-02-01// Author:	Johan Persson (johanp@aditus.nu)// Ver:		$Id: jpgraph_gradient.php,v 1.1.2.11 2004/06/12 14:29:18 aditus Exp $//// License:	This code is released under QPL// Copyright (C) 2003 Johan Persson//========================================================================*/// Styles for gradient color fillDEFINE("GRAD_VER",1);DEFINE("GRAD_VERT",1);DEFINE("GRAD_HOR",2);DEFINE("GRAD_MIDHOR",3);DEFINE("GRAD_MIDVER",4);DEFINE("GRAD_CENTER",5);DEFINE("GRAD_WIDE_MIDVER",6);DEFINE("GRAD_WIDE_MIDHOR",7);DEFINE("GRAD_LEFT_REFLECTION",8);DEFINE("GRAD_RIGHT_REFLECTION",9);DEFINE("GRAD_RAISED_PANEL",10);  //===================================================// CLASS Gradient// Description: Handles gradient fills. This is to be// considered a "friend" class of Class Image.//===================================================class Gradient {    var $img=null;    var $numcolors=100;//---------------// CONSTRUCTOR    function Gradient(&$img) {	$this->img = $img;    }    function SetNumColors($aNum) {	$this->numcolors=$aNum;    }//---------------// PUBLIC METHODS	    // Produce a gradient filled rectangle with a smooth transition between    // two colors.    // ($xl,$yt) 	Top left corner    // ($xr,$yb)	Bottom right    // $from_color	Starting color in gradient    // $to_color	End color in the gradient    // $style		Which way is the gradient oriented?    function FilledRectangle($xl,$yt,$xr,$yb,$from_color,$to_color,$style=1) {	switch( $style ) {		    case GRAD_VER:  		$steps = round(abs($xr-$xl));		$delta = $xr>=$xl ? 1 : -1;		$this->GetColArray($from_color,$to_color,$steps,$colors,$this->numcolors);		for( $i=0, $x=$xl; $i < $steps; ++$i ) {		    $this->img->current_color = $colors[$i];		    $this->img->Line($x,$yt,$x,$yb);		    $x += $delta;		}		break;	    case GRAD_HOR: 		$steps = round(abs($yb-$yt));		$delta = $yb>=$yt ? 1 : -1;		$this->GetColArray($from_color,$to_color,$steps,$colors,$this->numcolors);		for($i=0,$y=$yt; $i < $steps; ++$i) {		    $this->img->current_color = $colors[$i];		    $this->img->Line($xl,$y,$xr,$y);		    $y += $delta;		}		break;	    case GRAD_MIDHOR: 		$steps = round(abs($yb-$yt)/2);		$delta = $yb >= $yt ? 1 : -1;		$this->GetColArray($from_color,$to_color,$steps,$colors,$this->numcolors);		for($y=$yt, $i=0; $i < $steps;  ++$i) {		    $this->img->current_color = $colors[$i];		    $this->img->Line($xl,$y,$xr,$y);		    $y += $delta;		}		--$i;		if( abs($yb-$yt) % 2 == 1 ) --$steps;		for($j=0; $j < $steps; ++$j, --$i) {		    $this->img->current_color = $colors[$i];		    $this->img->Line($xl,$y,$xr,$y);		    $y += $delta;		}		$this->img->Line($xl,$y,$xr,$y);		break;	    case GRAD_MIDVER: 		$steps = round(abs($xr-$xl)/2);		$delta = $xr>=$xl ? 1 : -1;		$this->GetColArray($from_color,$to_color,$steps,$colors,$this->numcolors);		for($x=$xl, $i=0; $i < $steps; ++$i) {		    $this->img->current_color = $colors[$i];		    $this->img->Line($x,$yb,$x,$yt);		    $x += $delta;		}		--$i;		if( abs($xr-$xl) % 2 == 1 ) --$steps;		for($j=0; $j < $steps; ++$j, --$i) {		    $this->img->current_color = $colors[$i];		    $this->img->Line($x,$yb,$x,$yt);		    $x += $delta;		}		$this->img->Line($x,$yb,$x,$yt);				break;	    case GRAD_WIDE_MIDVER: 		$diff = round(abs($xr-$xl));		$steps = floor(abs($diff)/3);		$firststep = $diff - 2*$steps ; 		$delta = $xr >= $xl ? 1 : -1;		$this->GetColArray($from_color,$to_color,$firststep,$colors,$this->numcolors);		for($x=$xl, $i=0; $i < $firststep; ++$i) {		    $this->img->current_color = $colors[$i];		    $this->img->Line($x,$yb,$x,$yt);		    $x += $delta;		}		--$i;		$this->img->current_color = $colors[$i];		for($j=0; $j< $steps; ++$j) {		    $this->img->Line($x,$yb,$x,$yt);		    $x += $delta;		}				for($j=0; $j < $steps; ++$j, --$i) {		    $this->img->current_color = $colors[$i];						    $this->img->Line($x,$yb,$x,$yt);			    $x += $delta;		}						break;	    case GRAD_WIDE_MIDHOR:		$diff = round(abs($yb-$yt));		$steps = floor(abs($diff)/3);		$firststep = $diff - 2*$steps ; 		$delta = $yb >= $yt? 1 : -1;		$this->GetColArray($from_color,$to_color,$firststep,$colors,$this->numcolors);		for($y=$yt, $i=0; $i < $firststep;  ++$i) {		    $this->img->current_color = $colors[$i];		    $this->img->Line($xl,$y,$xr,$y);		    $y += $delta;		}		--$i;		$this->img->current_color = $colors[$i];		for($j=0; $j < $steps; ++$j) {		    $this->img->Line($xl,$y,$xr,$y);		    $y += $delta;		}		for($j=0; $j < $steps; ++$j, --$i) {		    $this->img->current_color = $colors[$i];						    $this->img->Line($xl,$y,$xr,$y);		    $y += $delta;		}						break;	    	    case GRAD_LEFT_REFLECTION: 		$steps1 = round(0.3*abs($xr-$xl));		$delta = $xr>=$xl ? 1 : -1;				$from_color = $this->img->rgb->Color($from_color);		$adj = 1.4;		$m = ($adj-1.0)*(255-min(255,min($from_color[0],min($from_color[1],$from_color[2]))));		$from_color2 = array(min(255,$from_color[0]+$m), 				    min(255,$from_color[1]+$m), min(255,$from_color[2]+$m));				$this->GetColArray($from_color2,$to_color,$steps1,$colors,$this->numcolors);		$n = count($colors);		for($x=$xl, $i=0; $i < $steps1 && $i < $n; ++$i) {		    $this->img->current_color = $colors[$i];		    $this->img->Line($x,$yb,$x,$yt);		    $x += $delta;		}		$steps2 = max(1,round(0.08*abs($xr-$xl)));		$this->img->SetColor($to_color);		for($j=0; $j< $steps2; ++$j) {		    $this->img->Line($x,$yb,$x,$yt);		    $x += $delta;		}		$steps = abs($xr-$xl)-$steps1-$steps2;		$this->GetColArray($to_color,$from_color,$steps,$colors,$this->numcolors);   		$n = count($colors);		for($i=0; $i < $steps && $i < $n; ++$i) {		    $this->img->current_color = $colors[$i];		    $this->img->Line($x,$yb,$x,$yt);		    $x += $delta;		}		break;	    case GRAD_RIGHT_REFLECTION: 		$steps1 = round(0.7*abs($xr-$xl));		$delta = $xr>=$xl ? 1 : -1;		$this->GetColArray($from_color,$to_color,$steps1,$colors,$this->numcolors);		$n = count($colors);		for($x=$xl, $i=0; $i < $steps1 && $i < $n; ++$i) {		    $this->img->current_color = $colors[$i];		    $this->img->Line($x,$yb,$x,$yt);		    $x += $delta;		}		$steps2 = max(1,round(0.08*abs($xr-$xl)));		$this->img->SetColor($to_color);		for($j=0; $j< $steps2; ++$j) {		    $this->img->Line($x,$yb,$x,$yt);		    $x += $delta;		}		$from_color = $this->img->rgb->Color($from_color);		$adj = 1.4;		$m = ($adj-1.0)*(255-min(255,min($from_color[0],min($from_color[1],$from_color[2]))));		$from_color = array(min(255,$from_color[0]+$m), 				    min(255,$from_color[1]+$m), min(255,$from_color[2]+$m));				$steps = abs($xr-$xl)-$steps1-$steps2;		$this->GetColArray($to_color,$from_color,$steps,$colors,$this->numcolors);   		$n = count($colors);		for($i=0; $i < $steps && $i < $n; ++$i) {		    $this->img->current_color = $colors[$i];		    $this->img->Line($x,$yb,$x,$yt);		    $x += $delta;		}		break;	    case GRAD_CENTER: 		$steps = ceil(min(($yb-$yt)+1,($xr-$xl)+1)/2);			$this->GetColArray($from_color,$to_color,$steps,$colors,$this->numcolors);		$dx = ($xr-$xl)/2;		$dy = ($yb-$yt)/2;		$x=$xl;$y=$yt;$x2=$xr;$y2=$yb;		$n = count($colors);		for($x=$xl, $i=0; $x < $xl+$dx && $y < $yt+$dy && $i < $n; ++$x, ++$y, --$x2, --$y2, ++$i) {		    $this->img->current_color = $colors[$i];					    $this->img->Rectangle($x,$y,$x2,$y2);		}		$this->img->Line($x,$y,$x2,$y2);		break;			    case GRAD_RAISED_PANEL:		// right to left 		$steps1 = $xr-$xl; 		$delta = $xr>=$xl ? 1 : -1; 		$this->GetColArray($to_color,$from_color,$steps1,$colors,$this->numcolors); 		$n = count($colors);		for($x=$xl, $i=0; $i < $steps1 && $i < $n; ++$i) { 		    $this->img->current_color = $colors[$i]; 		    $this->img->Line($x,$yb,$x,$yt); 		    $x += $delta; 		} 				// left to right 		$xr -= 3; 		$xl += 3; 		$yb -= 3; 		$yt += 3; 		$steps2 = $xr-$xl; 		$delta = $xr>=$xl ? 1 : -1; 		for($x=$xl, $j=$steps2; $j >= 0; --$j) { 		    $this->img->current_color = $colors[$j]; 		    $this->img->Line($x,$yb,$x,$yt); 		    $x += $delta; 		} 		break;	    default:		JpGraphError::Raise("Unknown gradient style (=$style).");		break;	}    }    // Fill a special case of a polygon with a flat bottom    // with a gradient. Can be used for filled line plots.    // Please note that this is NOT a generic gradient polygon fill    // routine. It assumes that the bottom is flat (like a drawing    // of a mountain)    function FilledFlatPolygon($pts,$from_color,$to_color) {	if( count($pts) == 0 ) return;		$maxy=$pts[1];	$miny=$pts[1];			$n = count($pts) ;	for( $i=0, $idx=0; $i < $n; $i += 2) {	    $x = round($pts[$i]);	    $y = round($pts[$i+1]);	    $miny = min($miny,$y);	    $maxy = max($maxy,$y);	}	    	$colors = array();	$this->GetColArray($from_color,$to_color,abs($maxy-$miny)+1,$colors,$this->numcolors);	for($i=$miny, $idx=0; $i <= $maxy; ++$i ) {	    $colmap[$i] = $colors[$idx++]; 	}	$n = count($pts)/2 ;	$idx = 0 ;	while( $idx < $n-1 ) {	    $p1 = array(round($pts[$idx*2]),round($pts[$idx*2+1]));	    $p2 = array(round($pts[++$idx*2]),round($pts[$idx*2+1]));			    // Find the largest rectangle we can fill	    $y = max($p1[1],$p2[1]) ;	    for($yy=$maxy; $yy > $y; --$yy) {		$this->img->current_color = $colmap[$yy];		$this->img->Line($p1[0],$yy,$p2[0]-1,$yy);	    }	    	    if( $p1[1] == $p2[1] ) continue; 	    // Fill the rest using lines (slow...)	    $slope = ($p2[0]-$p1[0])/($p1[1]-$p2[1]);	    $x1 = $p1[0];	    $x2 = $p2[0]; //-1;	    $start = $y;	    if( $p1[1] > $p2[1] ) {		while( $y >= $p2[1] ) {		    $x1=$slope*($start-$y)+$p1[0];		    $this->img->current_color = $colmap[$y];		    $this->img->Line($x1,$y,$x2,$y);		    --$y;		} 	    }	    else {		while( $y >= $p1[1] ) {		    $x2=$p2[0]+$slope*($start-$y);		    $this->img->current_color = $colmap[$y];		    $this->img->Line($x1,$y,$x2,$y);		    --$y;		} 	    }	}    }//---------------// PRIVATE METHODS	    // Add to the image color map the necessary colors to do the transition    // between the two colors using $numcolors intermediate colors    function GetColArray($from_color,$to_color,$arr_size,&$colors,$numcols=100) {	if( $arr_size==0 ) return;	// If color is given as text get it's corresponding r,g,b values	$from_color = $this->img->rgb->Color($from_color);	$to_color = $this->img->rgb->Color($to_color);			$rdelta=($to_color[0]-$from_color[0])/$numcols;	$gdelta=($to_color[1]-$from_color[1])/$numcols;	$bdelta=($to_color[2]-$from_color[2])/$numcols;	$colorsperstep	= $numcols/$arr_size;	$prevcolnum	= -1;	$from_alpha = $from_color[3];	$to_alpha = $to_color[3];	$adelta = ( $to_alpha - $from_alpha ) / $numcols ;	for ($i=0; $i < $arr_size; ++$i) {	    $colnum = floor($colorsperstep*$i);	    if ( $colnum == $prevcolnum ) 		$colors[$i]	= $colidx;	    else {		$r = floor($from_color[0] + $colnum*$rdelta);		$g = floor($from_color[1] + $colnum*$gdelta);		$b = floor($from_color[2] + $colnum*$bdelta);		$alpha = $from_alpha + $colnum*$adelta;		$colidx = $this->img->rgb->Allocate(sprintf("#%02x%02x%02x",$r,$g,$b),$alpha);		$colors[$i] = $colidx;	    }	    $prevcolnum = $colnum;	}    }	} // Class?>