/*

* 中文圆形印章类

* @example:

* $seal = new circleSeal('你我他坐站走东西南北中',75,6,24,0,0,16,40);

* $seal->doImg();

*/

class circleSeal {

private $sealString; //印章字符

private $strMaxLeng; //最大字符长度

private $sealRadius; //印章半径

private $rimWidth; //边框厚度

private $innerRadius; //内圆半径

private $startRadius; //五角星半径

private $startAngle; //五角星倾斜角度

private $backGround; //印章颜色

private $centerDot; //圆心坐标

private $img; //图形资源句柄

private $font; //指定的字体

private $fontSize; //指定字体大小

private $width; //图片宽度

private $height; //图片高度

private $points; //五角星各点坐标

private $charRadius; //字符串半径

private $charAngle; //字符串倾斜角度

private $spacing; //字符间隔角度

//构造方法

public function __construct($str ='', $rad = 75, $rmwidth = 6, $strad = 24, $stang = 0, $crang = 0, $fsize = 16, $inrad =0){

$this->sealString = empty($str) ? '印章测试字符串' : $str;

$this->strMaxLeng = 12;

$this->sealRadius = $rad;

$this->rimWidth = $rmwidth;

$this->startRadius = $strad;

$this->startAngle = $stang;

$this->charAngle = $crang;

$this->centerDot = array('x'=>$rad, 'y'=>$rad);

$this->font = dirname(__FILE__) .'/simkai.ttf';

$this->fontSize = $fsize;

$this->innerRadius = $inrad; //默认0,没有

$this->spacing = 1;

}

//创建图片资源

private function createImg(){

$this->width = 2 * $this->sealRadius;

$this->height = 2 * $this->sealRadius;

$this->img = imagecreate($this->width, $this->height);

imagecolorresolvealpha($this->img,255,255,255,127);

$this->backGround = imagecolorallocate($this->img,255,0,0);

}

//画印章边框

private function drawRim(){

for($i=0;$irimWidth;$i++){

imagearc($this->img,$this->centerDot['x'],$this->centerDot['y'],$this->width - $i,$this->height - $i,0,360,$this->backGround);

}

}

//画内圆

private function drawInnerCircle(){

imagearc($this->img,$this->centerDot['x'],$this->centerDot['y'],2*$this->innerRadius,2*$this->innerRadius,0,360,$this->backGround);

}

//画字符串

private function drawString(){

//编码处理

$charset = mb_detect_encoding($this->sealString);

if($charset != 'UTF-8'){

$this->sealString = mb_convert_encoding($this->sealString, 'UTF-8', 'GBK');

}

//相关计量

$this->charRadius = $this->sealRadius - $this->rimWidth - $this->fontSize; //字符串半径

$leng = mb_strlen($this->sealString,'utf8'); //字符串长度

if($leng > $this->strMaxLeng) $leng = $this->strMaxLeng;

$avgAngle = 360 / ($this->strMaxLeng); //平均字符倾斜度

//拆分并写入字符串

$words = array(); //字符数组

for($i=0;$i

$words[] = mb_substr($this->sealString,$i,1,'utf8');

$r = 630 + $this->charAngle + $avgAngle*($i - $leng/2) + $this->spacing*($i-1); //坐标角度

$R = 720 - $this->charAngle + $avgAngle*($leng-2*$i-1)/2 + $this->spacing*(1-$i); //字符角度

$x = $this->centerDot['x'] + $this->charRadius * cos(deg2rad($r)); //字符的x坐标

$y = $this->centerDot['y'] + $this->charRadius * sin(deg2rad($r)); //字符的y坐标

imagettftext($this->img, $this->fontSize, $R, $x, $y, $this->backGround, $this->font, $words[$i]);

}

}

//画五角星

private function drawStart(){

$ang_out = 18 + $this->startAngle;

$ang_in = 56 + $this->startAngle;

$rad_out = $this->startRadius;

$rad_in = $rad_out * 0.382;

for($i=0;$i<5;$i++){

//五个顶点坐标

$this->points[] = $rad_out * cos(2*M_PI/5*$i - deg2rad($ang_out)) + $this->centerDot['x'];

$this->points[] = $rad_out * sin(2*M_PI/5*$i - deg2rad($ang_out)) + $this->centerDot['y'];

//内凹的点坐标

$this->points[] = $rad_in * cos(2*M_PI/5*($i+1) - deg2rad($ang_in)) + $this->centerDot['x'];

$this->points[] = $rad_in * sin(2*M_PI/5*($i+1) - deg2rad($ang_in)) + $this->centerDot['y'];

}

imagefilledpolygon($this->img, $this->points, 10, $this->backGround);

}

//输出

private function outPut(){

header('Content-type:image/png');

imagepng($this->img);

imagedestroy($this->img);

}

//对外生成

public function doImg(){

$this->createImg();

$this->drawRim();

$this->drawInnerCircle();

$this->drawString();

$this->drawStart();

$this->outPut();

}

}