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Use GD library to generate images with shadow text_PHP tutorial

Jul 13, 2016 am 09:59 AM
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Use the GD library to generate images with shadow text

This article mainly introduces the method of using the GD library to generate images with shadow text. It is very detailed and recommended to everyone. Friends in need can refer to it

I recently used the GD library to generate images for WeChat public accounts. I studied the generation of text shadow effects in the GD library and also discovered the power of the GD library.

The GD library is an extension library for PHP to process graphics. The GD library provides a series of APIs for processing images. You can use the GD library to process images or generate images. On websites, the GD library is usually used to generate thumbnails, add watermarks to images, generate Chinese character verification codes, or generate reports on website data.

The installation of the GD library is available online, and many virtual spaces now support it, so I won’t go into details here. Below, I will introduce how to use the GD library through examples of my actual application code and related comments.

Original picture:

使用GD库生成带阴影文字的图片    帮客之家

Generate renderings:

The code is as follows:

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$str="北京";

$str2= "空气质量:轻度污染";

// 通过图片生成一个对象$im

$im = imagecreatefromjpeg("images/3.jpg");

//载入字体zt.ttf

$fnt = "zt.ttf";

//创建颜色,用于文字字体的白和阴影的黑

$white=imagecolorallocate($im,222,229,207);

$black=imagecolorallocate($im,50,50,50);

//创建关于相对图片位置的函数,方便调用

$top=100;

$left=60;

$top2=170;

//在图片中添加文字,imagettftext (image,size,angle, x, y,color,fontfile,text)

imagettftext($im,41, 0, $left 1, $top 1, $black, $fnt, $str);

imagettftext($im,41, 0, $left, $top, $white, $fnt, $str);

imagettftext($im,43, 0, $left 1,$top2 1 , $black, $fnt, $str2);

imagettftext($im,43, 0, $left,$top2, $white, $fnt, $str2);

//将$im输出

ImageJpeg($im);

//销毁$im对象

ImageDestroy($im);

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$str="Beijing"; $str2= "Air Quality: Mild Pollution"; // Generate an object $im from the image $im = imagecreatefromjpeg("images/3.jpg"); //Load font zt.ttf $fnt = "zt.ttf"; //Create colors, white for text font and black for shadow $white=imagecolorallocate($im,222,229,207); $black=imagecolorallocate($im,50,50,50); //Create a function about relative image position for easy calling $top=100; $left=60; $top2=170; //Add text to the image, imagettftext (image, size, angle, x, y, color, fontfile, text) imagettftext($im,41, 0, $left 1, $top 1, $black, $fnt, $str); imagettftext($im,41, 0, $left, $top, $white, $fnt, $str); imagettftext($im,43, 0, $left 1,$top2 1 , $black, $fnt, $str2); imagettftext($im,43, 0, $left,$top2, $white, $fnt, $str2); //Output $im ImageJpeg($im); //Destroy the $im object ImageDestroy($im);
Next, let’s explain in detail: Imagettftext (image, size, angle, x, y, color, fontfile, text) Imagettftext() draws the string text onto the image represented by the image, starting from the coordinates x, y (the upper left corner is 0, 0), the angle is angle, the color is color, and the TrueType font specified by fontfile is used document. The coordinates represented by x, y define the basic point of the first character approximately at the lower left corner of the character.  angle is expressed in degrees, with 0 degrees meaning the text is read from left to right and higher values ​​meaning counter-clockwise (i.e. a value of 90 means the text is read from bottom to top).  fontfile is the file name of the TrueType font you want to use. Text is a text string that can contain UTF-8 character sequences. Color is the index value of the color. The above is the entire content of this article, I hope you all like it. http://www.bkjia.com/PHPjc/975123.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/975123.htmlTechArticleUsing the GD library to generate images with shadow text. This article mainly introduces the use of the GD library to generate images with shadow text. The method is very detailed. I recommend it to everyone. Friends who need it can refer to it...
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