这篇文章主要介绍了关于PHP实现中文圆形印章的特效，有着一定的参考价值，现在分享给大家，有需要的朋友可以参考一下
心血来潮，写了个圆形印章生成器，字体的弧形旋转颇费功夫。总算效果还不错，代码存档。
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);
?>以上就是本文的全部内容，希望对大家的学习有所帮助，更多相关内容请关注PHP中文网！
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