imageellipse

(PHP 4 >= 4.0.6, PHP 5)

imageellipse — Draw an ellipse

Beschreibung

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

Draws an ellipse centered at the specified coordinates.

Parameter-Liste

image: Eine von den verschiedenen Erzeugungsfunktionen wie imagecreatetruecolor() gelieferte Grafikressource.
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().

Rückgabewerte

Gibt bei Erfolg TRUE zurück. Im Fehlerfall wird FALSE zurückgegeben.

Beispiele

Beispiel #1 imageellipse() example


<?php

// Create a blank image.
$image = imagecreatetruecolor(400, 300);

// Select the background color.
$bg = imagecolorallocate($image, 0, 0, 0);

// Fill the background with the color selected above.
imagefill($image, 0, 0, $bg);

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

?>

Das oben gezeigte Beispiel erzeugt eine ähnliche Ausgabe wie:

Anmerkungen

Hinweis:
This function requires GD 2.0.2 or later.

Siehe auch

imagefilledellipse() - Draw a filled ellipse
imagearc() - Draws an arc

4 BenutzerBeiträge:
- Beiträge aktualisieren...

themountainlion at gmail dot com
13.07.2008 18:28


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
7.06.2006 22:36


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
16.01.2005 15:23


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
5.12.2002 5:56


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); 

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