php gd problem

hi all, i am using GD library of php

Code:

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$x = 200; //largeur de mon image en PIXELS uniquement !
$y = 200; //hauteur de mon image en PIXELS uniquement !

$image = imagecreatetruecolor($x,$y);

$couleur = imagecolorallocate($image,255,0,0);

$coords = array('5','5',          // point 1
                '190', '190',    // point 2
                '160','40');      // point 3

imagefilledpolygon($image,$coords,3,$couleur);
imagepng($image,"1.png");
imagedestroy($image);

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the polygon did not filled with the red color why

You haven't declared that it's output should be an image.

PHP Code:

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header('Content-type: image/png'); 


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