imageantialias(3) [php man page]

IMAGEANTIALIAS(3)							 1							 IMAGEANTIALIAS(3)

imageantialias - Should antialias functions be used or not

SYNOPSIS

       bool imageantialias (resource  $image, bool  $enabled)

DESCRIPTION

	Activate  the fast drawing antialiased methods for lines and wired polygons. It does not support alpha components. It works using a direct
       blend operation. It works only with truecolor images.

	Thickness and styled are not supported.

	Using antialiased primitives with transparent background color can end with some unexpected results. The blend method uses the	background
       color as any other colors. The lack of alpha component support does not allow an alpha based antialiasing method.

PARAMETERS

	      o $
		image -An image resource, returned by one of the image creation functions, such as imagecreatetruecolor(3).

	      o $enabled
		- Whether to enable antialiasing or not.

RETURN VALUES

	Returns TRUE on success or FALSE on failure.

EXAMPLES

       Example #1

	      A comparison of two lines, one with anti-aliasing switched on

	      <?php
	      // Setup an anti-aliased image and a normal image
	      $aa = imagecreatetruecolor(400, 100);
	      $normal = imagecreatetruecolor(200, 100);

	      // Switch antialiasing on for one image
	      imageantialias($aa, true);

	      // Allocate colors
	      $red = imagecolorallocate($normal, 255, 0, 0);
	      $red_aa = imagecolorallocate($aa, 255, 0, 0);

	      // Draw two lines, one with AA enabled
	      imageline($normal, 0, 0, 200, 100, $red);
	      imageline($aa, 0, 0, 200, 100, $red_aa);

	      // Merge the two images side by side for output (AA: left, Normal: Right)
	      imagecopymerge($aa, $normal, 200, 0, 0, 0, 200, 100, 100);

	      // Output image
	      header('Content-type: image/png');

	      imagepng($aa);
	      imagedestroy($aa);
	      imagedestroy($normal);
	      ?>

	      The  above  example  will output something similar to:[NOT DISPLAYABLE MEDIA]Output of example : A comparison of two lines, one with
	      anti-aliasing switched on

NOTES

SEE ALSO

       imagecreatetruecolor(3).

PHP Documentation Group 													 IMAGEANTIALIAS(3)

IMAGECOLORALLOCATEALPHA(3)						 1						IMAGECOLORALLOCATEALPHA(3)

imagecolorallocatealpha - Allocate a color for an image

SYNOPSIS

       int imagecolorallocatealpha (resource  $image, int  $red, int  $green, int  $blue, int  $alpha)

DESCRIPTION

       imagecolorallocatealpha(3) behaves identically to imagecolorallocate(3) with the addition of the transparency parameter $alpha.

PARAMETERS

	      o $
		image -An image resource, returned by one of the image creation functions, such as imagecreatetruecolor(3).

	      o $red
		-Value of red component.

	      o $green
		-Value of green component.

	      o $blue
		-Value of blue component.

	      o $alpha
		- A value between 0 and 127.  0 indicates completely opaque while 127 indicates completely transparent.

	The $red, $green and $blue parameters are integers between 0 and 255 or hexadecimals between 0x00 and 0xFF.

RETURN VALUES

	A color identifier or FALSE if the allocation failed.

       Warning

	      This function may return Boolean FALSE, but may also return a non-Boolean value which evaluates to FALSE. Please read the section on
	      Booleans for more information. Use the === operator for testing the return value of this function.

CHANGELOG

       +--------+---------------------------------------------------+
       |Version |						    |
       |	|						    |
       |	|		     Description		    |
       |	|						    |
       +--------+---------------------------------------------------+
       | 5.1.3	|						    |
       |	|						    |
       |	|  Returns FALSE if the allocation  failed.  Previ- |
       |	| ously -1 was returned.			    |
       |	|						    |
       +--------+---------------------------------------------------+
EXAMPLES

       Example #1

	      Example of using imagecolorallocatealpha(3)

	      <?php
	      $size = 300;
	      $image=imagecreatetruecolor($size, $size);

	      // something to get a white background with black border
	      $back = imagecolorallocate($image, 255, 255, 255);
	      $border = imagecolorallocate($image, 0, 0, 0);
	      imagefilledrectangle($image, 0, 0, $size - 1, $size - 1, $back);
	      imagerectangle($image, 0, 0, $size - 1, $size - 1, $border);

	      $yellow_x = 100;
	      $yellow_y = 75;
	      $red_x	= 120;
	      $red_y	= 165;
	      $blue_x	= 187;
	      $blue_y	= 125;
	      $radius	= 150;

	      // allocate colors with alpha values
	      $yellow = imagecolorallocatealpha($image, 255, 255, 0, 75);
	      $red    = imagecolorallocatealpha($image, 255, 0, 0, 75);
	      $blue   = imagecolorallocatealpha($image, 0, 0, 255, 75);

	      // drawing 3 overlapped circle
	      imagefilledellipse($image, $yellow_x, $yellow_y, $radius, $radius, $yellow);
	      imagefilledellipse($image, $red_x, $red_y, $radius, $radius, $red);
	      imagefilledellipse($image, $blue_x, $blue_y, $radius, $radius, $blue);

	      // don't forget to output a correct header!
	      header('Content-Type: image/png');

	      // and finally, output the result
	      imagepng($image);
	      imagedestroy($image);
	      ?>

	      The above example will output something similar to:[NOT DISPLAYABLE MEDIA]Output of example : Example of using imagecolorallocateal-
	      pha()

NOTES

       Note

	      This function requires GD 2.0.1 or later (2.0.28 or later is recommended).

SEE ALSO

       imagecolorallocate(3), imagecolordeallocate(3).

PHP Documentation Group 												IMAGECOLORALLOCATEALPHA(3)