PHP/Graphics Image/imagearc

Drawing a Circle with imagearc()

   <source lang="html4strict">

<?php header("Content-type: image/png"); $image = imagecreate( 200, 200 ); $red = imagecolorallocate($image, 255,0,0); $blue = imagecolorallocate($image, 0,0,255 ); imagearc( $image, 99, 99, 180, 180, 0, 360, $blue ); imagefill( $image, 99, 99, $blue ); imagepng($image); ?>

 </source>
   
  

Using imagearc() to Draw Spirals

   <source lang="html4strict">

<?php

   define("WIDTH", 400);
   define("HEIGHT", 400);
   $img = imagecreate(WIDTH, HEIGHT);
   $bg = $white = imagecolorallocate($img, 0xFF, 0xFF, 0xFF);
   $black = imagecolorallocate($img, 0, 0, 0);
   imagerectangle($img, 0, 0, WIDTH-1, HEIGHT-1, $black);
   $center_x = (int)WIDTH/2;
   $center_y = (int)HEIGHT/2;
   $angle = 0;
   $radius = 0;
   while($radius <= WIDTH ) {
       imagearc($img, $center_x, $center_y, $radius,
                $radius, $angle-5, $angle, $black);
       $angle += 5;
       $radius++;
   }
   header("Content-Type: image/png");
   imagepng($img);

?>

 </source>