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.
imageellipse
(PHP 4 >= 4.0.6, PHP 5)
imageellipse — Draw an ellipse
Opis
bool imageellipse
( resource $image
, int $cx
, int $cy
, int $width
, int $height
, int $color
)
Draws an ellipse centered at the specified coordinates.
Parametry
- obraz
-
Zasób obrazu, zwrócony przez jedną z funkcji tworzących obrazy, taką jak 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().
Zwracane wartości
Zwraca TRUE w przypadku powodzenia, FALSE w przypadku błędu.
Przykłady
Przykład #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);
?>
Powyższy przykład wyświetli coś podobnego do:
Notatki
Informacja: This function requires GD 2.0.2 or later.
imageellipse
themountainlion at gmail dot com
13-Jul-2008 04:28
13-Jul-2008 04:28
simon_nuttall at hotmail dot com
07-Jun-2006 08:36
07-Jun-2006 08:36
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 02:23
16-Jan-2005 02:23
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
05-Dec-2002 04:56
05-Dec-2002 04:56
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);
----------------------------------------------------
