如何在php中绘制带有虚线边框的圆圈？

Question

I want to draw a circle with dashed border. imagearc function can be used for simple border. But I don't get any way for dashed border.

Thanks.

Answer 1

here it is

<?php 
function dashedcircle($im, $cx, $cy, $radius, $colour, $dashsize=5) { 

   $dash=false; 
   for ($angle=0; $angle<=(180+$dashsize); $angle+=$dashsize) { 
      $x = ($radius * cos(deg2rad($angle))); 
      $y = ($radius * sin(deg2rad($angle))); 

      if ($dash) { 
         imageline($im, $cx+$px, $cy+$py, $cx+$x, $cy+$y, $colour); 
         imageline($im, $cx-$px, $cx-$py, $cx-$x, $cy-$y, $colour); 
      } 
      $dash=!$dash; 
      $px=$x; 
      $py=$y; 
   } 
} 
?>

---

one more way of drawing a dashed-line circle.enjoy!

<?php

header("Content-type: image/jpeg");
$im = imagecreate(100,100);

$b   = imagecolorallocate ($im, 0, 0, 0);
$w   = imagecolorallocate ($im, 255, 255, 255);

$style = array ($b,$b,$b,$b,$b,$w,$w,$w,$w,$w);

imagesetstyle ($im, $style);

imagearc($im,50,50,100,100,0,360,IMG_COLOR_STYLED);

imagejpeg($im);
imagedestroy($im);
?>

Reference