imageline
(PHP 4, PHP 5, PHP 7, PHP 8)
imageline — 畫一條線段
說明
imageline(
resource
int
int
int
int
int
): bool
resource
$image,int
$x1,int
$y1,int
$x2,int
$y2,int
$color): bool
imageline() 用 color
顏色在影象 image 中從座標
x1，y1 到
x2，y2（影象左上角為
0, 0）畫一條線段。
示例 #1 畫一條粗線
<?php
function imagelinethick($image, $x1, $y1, $x2, $y2, $color, $thick = 1)
{
/* 下面兩行只在線段直角相交時好使
imagesetthickness($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);
}
?>