基于@AlecRust的想法，我实现了png文本服务。
演示在这里：
http://lingtalfi.com/services/pngtext?color=cc0000&size=10&text=Hello%20World
有四个参数：
- text：要显示的字符串
- 字体：不使用，因为在此演示中我只有Arial.ttf。
- fontSize：一个整数（默认为12）
- 颜色：6个字符的十六进制代码
请不要直接使用此服务（测试除外），而应使用我创建的提供该服务的类：
https://github.com/lingtalfi/WebBox/blob/master/Image/PngTextUtil.php
class PngTextUtil
{
/**
* Displays a png text.
*
* Note: this method is meant to be used as a webservice.
*
* Options:
* ------------
* - font: string = arial/Arial.ttf
* The font to use.
* If the path starts with a slash, it's an absolute path to the font file.
* Else if the path doesn't start with a slash, it's a relative path to the font directory provided
* by this class (the WebBox/assets/fonts directory in this repository).
* - fontSize: int = 12
* The font size.
* - color: string = 000000
* The color of the text in hexadecimal format (6 chars).
* This can optionally be prefixed with a pound symbol (#).
*
*
*
*
*
*
* @param string $text
* @param array $options
* @throws \Bat\Exception\BatException
* @throws WebBoxException
*/
public static function displayPngText(string $text, array $options = []): void
{
if (false === extension_loaded("gd")) {
throw new WebBoxException("The gd extension is not loaded!");
}
header("Content-type: image/png");
$font = $options['font'] ?? "arial/Arial.ttf";
$fontsize = $options['fontSize'] ?? 12;
$hexColor = $options['color'] ?? "000000";
if ('/' !== substr($font, 0, 1)) {
$fontDir = __DIR__ . "/../assets/fonts";
$font = $fontDir . "/" . $font;
}
$rgbColors = ConvertTool::convertHexColorToRgb($hexColor);
//--------------------------------------------
// GET THE TEXT BOX DIMENSIONS
//--------------------------------------------
$charWidth = $fontsize;
$charFactor = 1;
$textLen = mb_strlen($text);
$imageWidth = $textLen * $charWidth * $charFactor;
$imageHeight = $fontsize;
$logoimg = imagecreatetruecolor($imageWidth, $imageHeight);
imagealphablending($logoimg, false);
imagesavealpha($logoimg, true);
$col = imagecolorallocatealpha($logoimg, 255, 255, 255, 127);
imagefill($logoimg, 0, 0, $col);
$white = imagecolorallocate($logoimg, $rgbColors[0], $rgbColors[1], $rgbColors[2]); //for font color
$x = 0;
$y = $fontsize;
$angle = 0;
$bbox = imagettftext($logoimg, $fontsize, $angle, $x, $y, $white, $font, $text); //fill text in your image
$boxWidth = $bbox[4] - $bbox[0];
$boxHeight = $bbox[7] - $bbox[1];
imagedestroy($logoimg);
//--------------------------------------------
// CREATE THE PNG
//--------------------------------------------
$imageWidth = abs($boxWidth);
$imageHeight = abs($boxHeight);
$logoimg = imagecreatetruecolor($imageWidth, $imageHeight);
imagealphablending($logoimg, false);
imagesavealpha($logoimg, true);
$col = imagecolorallocatealpha($logoimg, 255, 255, 255, 127);
imagefill($logoimg, 0, 0, $col);
$white = imagecolorallocate($logoimg, $rgbColors[0], $rgbColors[1], $rgbColors[2]); //for font color
$x = 0;
$y = $fontsize;
$angle = 0;
imagettftext($logoimg, $fontsize, $angle, $x, $y, $white, $font, $text); //fill text in your image
imagepng($logoimg); //save your image at new location $target
imagedestroy($logoimg);
}
}
注意：如果不使用Universe框架，则需要替换以下行：
$rgbColors = ConvertTool::convertHexColorToRgb($hexColor);
使用此代码：
$rgbColors = sscanf($hexColor, "%02x%02x%02x");
在这种情况下，您的十六进制颜色必须正好为6个字符长（不要在其前面加上井号（＃））。
注意：最后，我没有使用此服务，因为我发现字体难看且更糟：无法选择文本。但是为了进行讨论，我认为该代码值得共享...
