IMAGELINE(3) 1 IMAGELINE(3)
imageline - Draw a line
SYNOPSIS
bool imageline (resource $image, int $x1, int $y1, int $x2, int $y2, int $color)
DESCRIPTION
Draws a line between the two given points.
PARAMETERS
o $
image -An image resource, returned by one of the image creation functions, such as imagecreatetruecolor(3).
o $x1
- x-coordinate for first point.
o $y1
- y-coordinate for first point.
o $x2
- x-coordinate for second point.
o $y2
- y-coordinate for second point.
o $color
- The line color. A color identifier created with imagecolorallocate(3).
RETURN VALUES
Returns TRUE on success or FALSE on failure.
EXAMPLES
Example #1
Drawing a thick line
<?php
function imagelinethick($image, $x1, $y1, $x2, $y2, $color, $thick = 1)
{
/* this way it works well only for orthogonal lines
imagesetthickness($image, $thick);
return imageline($image, $x1, $y1, $x2, $y2, $color);
*/
if ($thick == 1) {
return imageline($image, $x1, $y1, $x2, $y2, $color);
}
$t = $thick / 2 - 0.5;
if ($x1 == $x2 || $y1 == $y2) {
return imagefilledrectangle($image, round(min($x1, $x2) - $t), round(min($y1, $y2) - $t), round(max($x1, $x2) + $t), round(max($y1, $y2) + $t), $color);
}
$k = ($y2 - $y1) / ($x2 - $x1); //y = kx + q
$a = $t / sqrt(1 + pow($k, 2));
$points = array(
round($x1 - (1+$k)*$a), round($y1 + (1-$k)*$a),
round($x1 - (1-$k)*$a), round($y1 - (1+$k)*$a),
round($x2 + (1+$k)*$a), round($y2 - (1-$k)*$a),
round($x2 + (1-$k)*$a), round($y2 + (1+$k)*$a),
);
imagefilledpolygon($image, $points, 4, $color);
return imagepolygon($image, $points, 4, $color);
}
?>
SEE ALSO
imagecreatetruecolor(3), imagecolorallocate(3).
PHP Documentation Group IMAGELINE(3)