01 $width = 500;
02 $height = 500;
03
04 $im = imagecreatetruecolor($width, $height);
05
06 $red = imagecolorallocate($im, 230, 0, 0);
07 imagefill($im, 0, 0, $red);
08
09 $yellow = imagecolorallocate($im, 255, 255, 0);
10
11 //设定画出五角星的五个顶点形成的 正五边形的边长
12 $b=100;
13 $pi=3.14/180;
14
15 $p1x = 150;
16 $p1y = 250;
17
18 $p2x = 150+(cos(36*$pi)*$b);
19 $p2y = 250-(sin(36*$pi)*$b);
20
21 $p3x = 150+(2*cos(36*$pi)*$b);
22 $p3y = 250;
23
24 $p4x = $p3x-sin(18*$pi)*$b;
25 $p4y = 250+cos(18*$pi)*$b;
26
27 $p5x = 150+sin(18*$pi)*$b;
28 $p5y = 250+cos(18*$pi)*$b;
29
30 //连接相应的点 画线
31 imageline($im, $p1x, $p1y, $p3x, $p3y, $yellow);
32 imageline($im, $p1x, $p1y, $p4x, $p4y, $yellow);
33
34 imageline($im, $p2x, $p2y, $p4x, $p4y, $yellow);
35 imageline($im, $p2x, $p2y, $p5x, $p5y, $yellow);
36
37 imageline($im, $p3x, $p3y, $p5x, $p5y, $yellow);
38
39 header('Content-Type:image/png');
40
41 imagepng($im);
42
43 imagedestroy($im);
44
45 ?>
