imageellipse

(PHP 4 >= 4.0.6, PHP 5)

imageellipse — Draw an ellipse

Popis

bool imageellipse ( resource $image, int $cx, int $cy, int $width, int $height, int $color )

Draws an ellipse centered at the specified coordinates.

Seznam parametrů

image: An image resource, returned by one of the image creation functions, such as imagecreatetruecolor().
cx: x-coordinate of the center
cy: y-coordinate of the center
width: The ellipse width
height: The ellipse height
color: The color of the ellipse. A color identifier created with imagecolorallocate()

Návratové hodnoty

Vrací TRUE při úspěchu, FALSE při selhání.

Příklady

Příklad 795. imageellipse() example


<?php



// create a blank image

$image = imagecreatetruecolor(400, 300);



// fill the background color

$bg = imagecolorallocate($image, 0, 0, 0);



// choose a color for the ellipse

$col_ellipse = imagecolorallocate($image, 255, 255, 255);



// draw the ellipse

imageellipse($image, 200, 150, 300, 200, $col_ellipse);



// output the picture

header("Content-type: image/png");

imagepng($image);



?>

Výše uvedený příklad vypíše něco jako:

Poznámky

Poznámka: This function requires GD 2.0.2 or later.

Viz také

imagefilledellipse()

imagearc()

imagefill

imagedestroy

Last updated: Sat, 24 Mar 2007

add a note User Contributed Notes
imageellipse

themountainlion at gmail dot com
13-Jul-2008 09:28


In example #1 above, the variable $bg is set but not used. Set the background to anything but black ,and it won't take effect. The example needs 



imagefill($image, 0, 0, $bg);



Some other image function examples have the same issue.

simon_nuttall at hotmail dot com
07-Jun-2006 01:36


This is an optimised and bug fixed version of nojer at yahoo dot com's rotatedellipse function. I've changed it so that the arguments are compatible with imageellipse. See notes on imagearc for original version.



<?php



function rotatedellipse($im, $cx, $cy, $width, $height, $rotateangle, $colour, $filled=false) {

  // modified here from nojer's version

  // Rotates from the three o-clock position clockwise with increasing angle.

  // Arguments are compatible with imageellipse.



  $width=$width/2;

  $height=$height/2;



  // This affects how coarse the ellipse is drawn.

  $step=3;



  $cosangle=cos(deg2rad($rotateangle));

  $sinangle=sin(deg2rad($rotateangle));



  // $px and $py are initialised to values corresponding to $angle=0.

  $px=$width * $cosangle;

  $py=$width * $sinangle;

  

  for ($angle=$step; $angle<=(180+$step); $angle+=$step) {

    

    $ox = $width * cos(deg2rad($angle));

    $oy = $height * sin(deg2rad($angle));

    

    $x = ($ox * $cosangle) - ($oy * $sinangle);

    $y = ($ox * $sinangle) + ($oy * $cosangle);

 

    if ($filled) {

      triangle($im, $cx, $cy, $cx+$px, $cy+$py, $cx+$x, $cy+$y, $colour);

      triangle($im, $cx, $cy, $cx-$px, $cy-$py, $cx-$x, $cy-$y, $colour);

    } else {

      imageline($im, $cx+$px, $cy+$py, $cx+$x, $cy+$y, $colour);

      imageline($im, $cx-$px, $cy-$py, $cx-$x, $cy-$y, $colour);

    }

    $px=$x;

    $py=$y;

  }

}



function triangle($im, $x1,$y1, $x2,$y2, $x3,$y3, $colour) {

   $coords = array($x1,$y1, $x2,$y2, $x3,$y3);

   imagefilledpolygon($im, $coords, 3, $colour);

}



?>

julian
16-Jan-2005 06:23


if you want to display an ellipse in the upper left corner of an image, you can easily calculate the corresponding cx and cy values. this example will draw an ellipse having the same width and height as the image.



<?php



$ellipse_width = 100;

$ellipse_height = 200;



$ellipse_cx = ($ellipse_width / 2);

$ellipse_cy = ($ellipse_height / 2);



$img_x = $ellipse_width;

$img_y = $ellipse_height;



$img = imagecreate($img_x, $img_y);

$bg = imagecolorallocate($img, 255,255,255);



$ellipse_color = imagecolorallocate($img, 0, 0, 0);



imageellipse($img, $ellipse_cx, $ellipse_cy, $ellipse_width, $ellipse_height, $ellipse_color);



header("Content-type: image/png");

imagepng($img);

imagedestroy($img);



?>

agentyoungsoo at hanmail dot net
04-Dec-2002 08:56


When you wana use "ImageEllipse" function 

in under GD 2.0.2 version, you can use "ImageArc" like bellow



----------------------------------------------------

$file_name = "test.png";



$screen_x = 300;

$screen_y = 200;



$x1 = $screen_x / 2;

$y1 = $screen_y / 2;



$radius = 30;



$image = ImageCreate($screen_x, $screen_y);

$black = ImageColorAllocate($image, 0,0,0);



ImageArc($image, $x1, $y1, $radius , $radius , 0, 360, $black);



ImagePng($image, $file_name); 

ImageDestroy($image); 

----------------------------------------------------

add a note

imagefill

imagedestroy

Last updated: Sat, 24 Mar 2007