jpgraph_gradient.php
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上传日期:2010-02-11
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- <?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 2003/10/10 03:37:56 wwf Exp $
- //
- // License: This code is released under QPL
- // Copyright (C) 2003 Johan Persson
- //========================================================================
- */
-
- //===================================================
- // CLASS Gradient
- // Description: Handles gradient fills. This is to be
- // considered a "friend" class of Class Image.
- //===================================================
- class Gradient {
- var $img=null;
- //---------------
- // CONSTRUCTOR
- function Gradient(&$img) {
- $this->img = $img;
- }
- //---------------
- // PUBLIC METHODS
- // Produce a gradient filled rectangle with a smooth transition between
- // two colors.
- // ($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 1: // HORIZONTAL
- $steps = abs($xr-$xl);
- $delta = $xr>=$xl ? 1 : -1;
- $this->GetColArray($from_color,$to_color,$steps,$colors);
- 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 2: // VERTICAL
- $steps = abs($yb-$yt);
- $delta = $yb>=$yt ? 1 : -1;
- $this->GetColArray($from_color,$to_color,$steps,$colors);
- for($i=0,$y=$yt; $i<$steps; ++$i) {
- $this->img->current_color = $colors[$i];
- $this->img->Line($xl,$y,$xr,$y);
- $y += $delta;
- }
- break;
- case 3: // VERTICAL FROM MIDDLE
- $steps = abs($yb-$yt)/2;
- $delta = $yb>=$yt ? 1 : -1;
- $this->GetColArray($from_color,$to_color,$steps,$colors);
- for($y=$yt, $i=0; $i < $steps; ++$i) {
- $this->img->current_color = $colors[$i];
- $this->img->Line($xl,$y,$xr,$y);
- $y += $delta;
- }
- --$i;
- 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 4: // HORIZONTAL FROM MIDDLE
- $steps = abs($xr-$xl)/2;
- $delta = $xr>=$xl ? 1 : -1;
- $this->GetColArray($from_color,$to_color,$steps,$colors);
- for($x=$xl, $i=0; $i<$steps; ++$i) {
- $this->img->current_color = $colors[$i];
- $this->img->Line($x,$yb,$x,$yt);
- $x += $delta;
- }
- --$i;
- 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 6: // HORIZONTAL WIDER MIDDLE
- $steps = abs($xr-$xl)/3;
- $delta = $xr>=$xl ? 1 : -1;
- $this->GetColArray($from_color,$to_color,$steps,$colors);
- for($x=$xl, $i=0; $i < $steps; ++$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 8: // LEFT REFLECTION
- $steps1 = round(0.3*abs($xr-$xl));
- $delta = $xr>=$xl ? 1 : -1;
- $this->GetColArray($from_color.':1.3',$to_color,$steps1,$colors);
- for($x=$xl, $i=0; $i < $steps1; ++$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,$colors);
- for($i=0; $i < $steps; ++$i) {
- $this->img->current_color = $colors[$i];
- $this->img->Line($x,$yb,$x,$yt);
- $x += $delta;
- }
- break;
- case 9: // RIGHT REFLECTION
- $steps1 = round(0.7*abs($xr-$xl));
- $delta = $xr>=$xl ? 1 : -1;
- $this->GetColArray($from_color,$to_color,$steps1,$colors);
- for($x=$xl, $i=0; $i < $steps1; ++$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,$from_color.':1.3',$steps,$colors);
- for($i=0; $i < $steps; ++$i) {
- $this->img->current_color = $colors[$i];
- $this->img->Line($x,$yb,$x,$yt);
- $x += $delta;
- }
- break;
- case 7: // VERTICAL WIDER MIDDLE
- $steps = abs($yb-$yt)/3;
- $delta = $yb>=$yt? 1 : -1;
- $this->GetColArray($from_color,$to_color,$steps,$colors);
- for($y=$yt, $i=0; $i<$steps; ++$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 5: // Rectangle
- $steps = floor(min(($yb-$yt)+1,($xr-$xl)+1)/2);
- $this->GetColArray($from_color,$to_color,$steps,$colors);
- $dx = ($xr-$xl)/2;
- $dy = ($yb-$yt)/2;
- $x=$xl;$y=$yt;$x2=$xr;$y2=$yb;
- for($x=$xl, $i=0; $x<$xl+$dx && $y<$yt+$dy ; ++$x, ++$y, --$x2, --$y2, ++$i) {
- assert($i<count($colors));
- $this->img->current_color = $colors[$i];
- $this->img->Rectangle($x,$y,$x2,$y2);
- }
- $this->img->Line($x,$y,$x2,$y2);
- break;
- default:
- die("JpGraph Error: Unknown gradient style (=$style).");
- break;
- }
- }
- //---------------
- // 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;
- $prevcolnum = -1;
- for ($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);
- $colidx = $this->img->rgb->Allocate(sprintf("#%02x%02x%02x",$r,$g,$b));
- $colors[$i] = $colidx;
- }
- $prevcolnum = $colnum;
- }
- }
- } // Class
- ?>