如何使用php垂直/水平翻转文本?

imagerotate :

旋转中心是图像的中心,并且旋转后的图像可能具有与原始图像不同的尺寸。

镜子 this 代码段有帮助(不过,它的性能不是很好,因为它逐像素复制。)

对于快速高级图像编辑操作, ImageMagick

here ,也可以使用 ImageMagick

未经测试。。。但这似乎应该起作用,由其他gd函数组成(可能缓慢):

function flipImageHorizontal($im){
  $width = imagesx($im);
  $height = imagesy($im);

  for($y = 0; $y < $height; $y++){          // for each column
    for($x = 0; $x < ($width >> 1); $x++){  // for half the pixels in the row       

       // get the color on the left side
       $rgb = imagecolorat($im, $x, $y);
       $colors = imagecolorsforindex($im, $rgb);
       $current_color = imagecolorallocate($im, $colors["red"], $colors["green"], $colors["blue"]);

       // get the color on the right side (mirror)
       $rgb = imagecolorat($im, $width - $x, $y);
       $colors = imagecolorsforindex($im, $rgb);
       $mirror_color = imagecolorallocate($im, $colors["red"], $colors["green"], $colors["blue"]);

       // swap the colors
       imagesetpixel($im, $x, $y, $mirror_color);        
       imagesetpixel($im, $width - $x, $y, $color);         
    }
  }
}

function flipImageVertical($im){
  $width = imagesx($im);
  $height = imagesy($im);

  for($x = 0; $x < $width; $x++){           // for each row
    for($y = 0; $y < ($height >> 1); $y++){ // for half the pixels in the col

       // get the color on the top
       $rgb = imagecolorat($im, $x, $y);
       $colors = imagecolorsforindex($im, $rgb);
       $current_color = imagecolorallocate($im, $colors["red"], $colors["green"], $colors["blue"]);

       // get the color on the bottom (mirror)
       $rgb = imagecolorat($im, $x, $height - $y);
       $colors = imagecolorsforindex($im, $rgb);
       $mirror_color = imagecolorallocate($im, $colors["red"], $colors["green"], $colors["blue"]);

       // swap the colors
       imagesetpixel($im, $x, $y, $mirror_color);        
       imagesetpixel($im, $x, $height - $y, $color);         
    }
  }
}

bool imagestring ( resource $image , int $font , int $x , int $y , string $string , int $color ) 从一个文本字符串创建一个图像,然后通过我上面写的适当的翻转函数运行它。。。

要在PHP中将垂直文本添加到现有图像中,请使用函数

imagettftext($im, 10, $angle, $x, $y, $black, $font, $text);

http://www.php.net/manual/en/function.imagettfbbox.php#refsect1-function.imagettfbbox-returnvalues

提示:

也许就这么简单?

function toVertical ($string)
{

   foreach (str_split($string) as $letter)
   {
       $newStr.="$letter\n";
   }
   return $newStr;
}


function toHorizontal($string)
{
   foreach(explode("\n",$string) as $letter)
   {
        $newStr.=$letter;
   }
   return $newStr;
}

$v = toVertical("This string should be printed vertically");
echo $v;
$h = toHorizontal($v);
echo $h;


---------- PHP Execute ----------
T
h
i
s

s
t
r
i
n
g

s
h
o
u
l
d

b
e

p
r
i
n
t
e
d

v
e
r
t
i
c
a
l
l
y
This string should be printed vertically
Output completed (0 sec consumed)