Description:
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imagefilledellipse draws a distorted shape when the size is big enough


Test script:
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// Ellipse looks fine - size 500x500
$image = imagecreatetruecolor(500, 500);
$color = imagecolorallocate($image, 255, 0, 0);
imagefilledellipse($image, 250, 250, 500, 500, $color);
imagepng($image, 'D:/pass.png');
imagedestroy($image);

// Ellipse is distorted - size 5000x5000
$image = imagecreatetruecolor(5000, 5000);
$color = imagecolorallocate($image, 255, 0, 0);
imagefilledellipse($image, 2500, 2500, 5000, 5000, $color);
imagepng($image, 'D:/fail.png');
imagedestroy($image);


Expected result:
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Ellipse should look like ellipse

Actual result:
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Ellipse is distorted