[PHP] GD, Text and Transparency

[eastman.uk]

Ok, here we go...

I have a script that generates a PNG image, sets the background as transparent, then puts a string in the center of the image. The only problem is that the text looks horrible when the background is transparent...

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

$fontsize = 12;
$font = 'verdana.ttf';
$text = $_GET['text'];

$size = imagettfbbox($fontsize, 0, $font, $text);
$width = $size[2] + $size[0] + 8;
$height = abs($size[1]) + abs($size[7]) + 5;

$im = imagecreatetruecolor($width, $height);

$white = imagecolorallocate($im, 255, 255, 255);
$black = imagecolorallocate($im, 0, 0, 0);

imagefilledrectangle( $im, 0, 0, $width, $height, $white );
imagecolortransparent($im, $white);

$xcoord = 0;
$ycoord = $height - 3;

imagefttext($im, $fontsize, 0, $xcoord, $ycoord, $black, $font, $text);

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

With a plain white background:

With a transparent background:

I want the text to appear as it does in the image with the white background, though with a transparent background! Any help?

[eastman.uk]

Well, seems like I didn't think this one through very well...

Just set the initial background colour to one which is close to the background colour on the page... Works for me since the image is all based around one colour!

No idea if there is another way around it, like if the page had two contrasting background colours... But that's a problem for another day! Problem solved :)

[apairet]

Did someone found any decent solution to that problem?

[apairet]

  apairet said:

Did someone found any decent solution to that problem?

I just found the solution...

<?php
	include("imgConst.php"); // contains font linkage and fontSize
	$text = $_GET[text];
	$arrayCoord = imagettfbbox($fontSize, 0, $font, $text);

	// Cr?ation ayant la taille du texte ? inclure
	$Neg = -1;
	$x = $arrayCoord[4];
	$baseLine = $arrayCoord[5] * $Neg;
	$y = $baseLine + 20;

	$imgTxt = @imagecreatetruecolor($x, $y);

	// Important stuff
	// Allocate a transparent background color
	$bgColor = ImageColorAllocateAlpha($imgTxt, 255, 255, 255, 127);
	// ..and a non-transparent text color
	$textColor = ImageColorAllocate($imgTxt, 0xFF, 0x00, 0x00);	

	// Turn on full alpha channel saving for PNG images
	imageSaveAlpha($imgTxt,true);



	// Fill with transparent and text with the other
	ImageFill($imgTxt, 0, 0 , $bgColor); 
	imagefttext($imgTxt, $fontSize, 0, 0, $baseLine, $textColor, $font, $text);

	// Affichage de l'image sur le navigateur
	header('Content-Type: image/png');

	imagepng($imgTxt);
	imagedestroy($imgTxt);
?>