Draw a string vertically

bool imagestringup ( resource $image , int $font , int $x , int $y , string $string , int $color )

Draws a string vertically at the given coordinates.

image: An image resource, returned by one of the image creation functions, such as imagecreatetruecolor().
font: Can be 1, 2, 3, 4, 5 for built-in fonts in latin2 encoding (where higher numbers corresponding to larger fonts) or any of your own font identifiers registered with imageloadfont().
x: x-coordinate of the upper left corner
y: y-coordinate of the upper left corner
sring: The string to be written
color: A color identifier created with imagecolorallocate()

Returns TRUE on success or FALSE on failure.

imagestringup