<?php
# written by: DJ Mike 04/21/08
header("Content-type: image/jpeg");
$im_width = 550;
$im_height = 380;
$im = imagecreatetruecolor($im_width, $im_height);
$background_color = imagecolorallocate($im, 0, 0, 0);

$start = rand( 0, 360);
$end = $start + 360;
$size_change = rand( 1, 2);
$size_change = $size_change/6;
imagesetthickness( $im, rand( 6,10) );

$lobe = rand( 3, 7);

# $increment = (3/$lobe)/2;
$increment = rand( 0,1 )/10;
$increment = .1+$increment;

# initialize red & blue
$red = rand( 0, 255 );
$green = rand( 0, 255 );
$blue = rand( 0, 255 );
# how colors will change
$red_step = rand(1,20);
$red_step = $red_step-10;
$green_step = rand(1,20);
$green_step = $green_step-10;
$blue_step = rand(1,20);
$blue_step = $blue_step-10;

# initilize width & height
$width = 2;
$height = 2;

$length = rand( 90, 270);
$start = rand( 0, 360);
$end = $start + $length;
$halfway = $start+$length/2;

for ($count=$start; $count<=$halfway; $count = $count+$increment )
{ 
# basic formula is: radius = 3sin(theta)
$r = sin( $lobe*deg2rad( $count ) );

# convert from polar to coordinate
$x = $r * ( cos( deg2rad( $count ) ) );
$y = $r * ( sin( deg2rad( $count ) ) );

# results are only from 0 to 1 so multiply by 175
# Add width/2 & height/2 to center
$x = ($x * 175)+($im_width/2);
$y = ($y * 175)+($im_height/2);

## step colors
$red = $red+$red_step;
$green = $green+$green_step;
$blue = $blue+$blue_step;
## loop color if too big or small
if ( $red < 0 ) { $red = 255+$red; }
if ( $red > 255 ) { $red = $red-255; }
##
if ( $green < 0 ) { $green = 255+$green; }
if ( $green > 255 ) { $green = $green-255; }
##
if ( $blue < 0 ) { $blue = 255+$blue; }
if ( $blue > 255 ) { $blue = $blue-255; }
## allocate color
$circle_color = imagecolorallocate($im, $red, $green, $blue );


$width = $width+$size_change;
$height = $height+$size_change;

imagefilledarc( $im, $x, $y, $width, $height, 0, 360, $circle_color, IMG_ARC_PIE+IMG_ARC_NOFILL );

} 

for ($count=$halfway; $count<=$end; $count = $count+$increment )
{ 
# basic formula is: radius = 3sin(theta)
$r = sin( $lobe*deg2rad( $count ) );

# convert from polar to coordinate
$x = $r * ( cos( deg2rad( $count ) ) );
$y = $r * ( sin( deg2rad( $count ) ) );

# results are only from 0 to 1 so multiply by 175
# Add 200 to center
$x = ($x * 175)+($im_width/2);
$y = ($y * 175)+($im_height/2);

## step colors
$red = $red+$red_step;
$green = $green+$green_step;
$blue = $blue+$blue_step;
## loop color if too big or small
if ( $red < 0 ) { $red = 255+$red; }
if ( $red > 255 ) { $red = $red-255; }
##
if ( $green < 0 ) { $green = 255+$green; }
if ( $green > 255 ) { $green = $green-255; }
##
if ( $blue < 0 ) { $blue = 255+$blue; }
if ( $blue > 255 ) { $blue = $blue-255; }
## allocate color
$circle_color = imagecolorallocate($im, $red, $green, $blue );

$width = $width-$size_change;
$height = $height-$size_change;


imagefilledarc( $im, $x, $y, $width, $height, 0, 360, $circle_color, IMG_ARC_PIE+IMG_ARC_NOFILL );

} 

header("Expires: Mon, 26 Jul 1997 05:00:00 GMT");
header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
header("Cache-Control: no-store, no-cache, must-revalidate");
header("Cache-Control: post-check=0, pre-check=0", false);
header("Pragma: no-cache");

imagejpeg($im);
imagedestroy($im);
?>