PHP实现中文圆形印章特效

方法一：

<?php
/*
 * 中文圆形印章类
 * @author lkk/lianq.net
 * @create on 10:03 2012-5-29
 * @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($i=0;$i<$this->rimWidth;$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;$i<$leng;$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();
 }
}

方法二：

<?php
@$hos=iconv("GBK", "UTF-8", $_GET["hos"]);
if(!isset($hos))
exit;

$im=ImageCreate(150,150);
$gray=ImageColorResolveAlpha($im,200,200,200,127);
$red=ImageColorAllocate($im,230,150,150);

for($i=0;$i<6;$i++)
ImageArc($im,75,75,148-$i,148-$i,0,360,$red);

$stock='C:\WINDOWS\Fonts\simkai.ttf';
$point="★";
$size=30;
ImageTTFText($im,$size,0,72-$size/2,72+$size/2,$red,$stock,$point);

$a=75;$b=-75;//中心点坐标
$r=65;$m=40;//半径，角度
$size=16;//字体大小
$r=$r-$size;

$word=array();
$max=18;
$count=mb_strlen($hos,'utf8');
if($count>$max)$count=$max;
if($count>12)
$m=floor(360/$count);
else if($count>5)
$m-=$count;

for($i=0;$i<$count;$i++)
$word[]=mb_substr($hos,$i,1,'utf8');

$j=floor($count/2);
if($j!=$count/2)
{
 for($i=$j;$i>=0;$i--)
 {
 $arc=$m*($j-$i)+$size/2;
 $x=round($r*cos((90+$arc)*M_PI/180))+$a;
 $y=-1*(round($r*sin((90+$arc)*M_PI/180))+$b);
 if($arc<10)$arc=0; 
 ImageTTFText($im,$size,$arc,$x,$y,$red,$stock,$word[$i]);
 $arc=$m*($j-$i)-$size/2;
 $x=round($r*cos((90-$arc)*M_PI/180))+$a;
 $y=-1*(round($r*sin((90-$arc)*M_PI/180))+$b);
 if($arc<10)$arc=0; 
 ImageTTFText($im,$size,-$arc,$x,$y,$red,$stock,$word[$j+$j-$i]);
 }
}
else
{
 $j=$j-1;
 for($i=$j;$i>=0;$i--)
 {
 $arc=$m/2+$m*($j-$i)+$size/2;
 $x=round($r*cos((90+$arc)*M_PI/180))+$a;
 $y=-1*(round($r*sin((90+$arc)*M_PI/180))+$b);
 ImageTTFText($im,$size,$arc,$x,$y,$red,$stock,$word[$i]); 
 $arc=$m/2+$m*($j-$i)-$size/2;
 $x=round($r*cos((90-$arc)*M_PI/180))+$a;
 $y=-1*(round($r*sin((90-$arc)*M_PI/180))+$b);
 ImageTTFText($im,$size,-$arc,$x,$y,$red,$stock,$word[$j+$j+1-$i]);
 }
}

header('Content-Type:image/png');
ImagePNG($im);
?>

以上所述就是本文的全部内容了，希望大家能够喜欢