php 生成文字png图片的代码

使用GD生成文字图片是php一项比较常用的功能，笔者今天介绍的是生成文字png图片的函数。需要的朋友可以参考下。

 
<? 
/* 
php生成文字png图片，可以使用如下方式调用函数: 
http://www.yourdomian.com/text_png.php3?msg=helloworld+class&rot=15&size=48&font=fonts/ARIAL.TTF 
*/ 
Header("Content-type: image/png"); 
class textPNG { 
var $font = 'fonts/TIMES.TTF'; //默认字体. 相对于脚本存放目录的相对路径. 
var $msg = "undefined"; // 默认文字. 
var $size = 24; 
var $rot = 0; // 旋转角度. 
var $pad = 0; // 填充. 
var $transparent = 1; // 文字透明度. 
var $red = 0; // 在黑色背景中... 
var $grn = 0; 
var $blu = 0; 
var $bg_red = 255; // 将文字设置为白色. 
var $bg_grn = 255; 
var $bg_blu = 255; 
function draw() { 
$width = 0; 
$height = 0; 
$offset_x = 0; 
$offset_y = 0; 
$bounds = array(); 
$image = ""; 
// 确定文字高度. 
$bounds = ImageTTFBBox($this->size, $this->rot, $this->font, "W"); 
if ($this->rot < 0) { 
$font_height = abs($bounds[7]-$bounds[1]); 
} else if ($this->rot > 0) { 
$font_height = abs($bounds[1]-$bounds[7]); 
} else { 
$font_height = abs($bounds[7]-$bounds[1]); 
} 
// 确定边框高度. 
$bounds = ImageTTFBBox($this->size, $this->rot, $this->font, $this->msg); 
if ($this->rot < 0) { 
$width = abs($bounds[4]-$bounds[0]); 
$height = abs($bounds[3]-$bounds[7]); 
$offset_y = $font_height; 
$offset_x = 0; 
} else if ($this->rot > 0) { 
$width = abs($bounds[2]-$bounds[6]); 
$height = abs($bounds[1]-$bounds[5]); 
$offset_y = abs($bounds[7]-$bounds[5])+$font_height; 
$offset_x = abs($bounds[0]-$bounds[6]); 
} else { 
$width = abs($bounds[4]-$bounds[6]); 
$height = abs($bounds[7]-$bounds[1]); 
$offset_y = $font_height;; 
$offset_x = 0; 
} 
$image = imagecreate($width+($this->pad*2)+1,$height+($this->pad*2)+1); 
$background = ImageColorAllocate($image, $this->bg_red, $this->bg_grn, $this->bg_blu); 
$foreground = ImageColorAllocate($image, $this->red, $this->grn, $this->blu); 
if ($this->transparent) ImageColorTransparent($image, $background); 
ImageInterlace($image, false); 
// 画图. 
ImageTTFText($image, $this->size, $this->rot, $offset_x+$this->pad, $offset_y+$this->pad, $foreground, $this->font, $this->msg); 
// 输出为png格式. 
imagePNG($image); 
} 
} 
$text = new textPNG; 
if (isset($msg)) $text->msg = $msg; // 需要显示的文字 
if (isset($font)) $text->font = $font; // 字体 
if (isset($size)) $text->size = $size; // 文字大小 
if (isset($rot)) $text->rot = $rot; // 旋转角度 
if (isset($pad)) $text->pad = $pad; // padding 
if (isset($red)) $text->red = $red; // 文字颜色 
if (isset($grn)) $text->grn = $grn; // .. 
if (isset($blu)) $text->blu = $blu; // .. 
if (isset($bg_red)) $text->bg_red = $bg_red; // 背景颜色. 
if (isset($bg_grn)) $text->bg_grn = $bg_grn; // .. 
if (isset($bg_blu)) $text->bg_blu = $bg_blu; // .. 
if (isset($tr)) $text->transparent = $tr; // 透明度 (boolean). 
$text->draw(); 
?>