如何在PHP中将字符串转换为小型大写字母？

I am trying to convert a strint composed of "standard" upper and lower case letters to small capitals, in PHP. There is no information about small caps in the php.net docs.

Small capitals are, in my understanding, this thing :

Hᴇʟʟᴏ ᴛʜᴇʀᴇ

(generated with this site : https://fsymbols.com/generators/smallcaps/)

For instance, here is the small cap version of a t : http://www.fileformat.info/info/unicode/char/1d1b/index.htm

I searched the web for a longtime and found nothin in PHP. I know that CSS let you do that by using

font-variant: small-caps;

But I need to do this on the server side for what I do. Is this possible in PHP ?

EDIT: To complete my question, I am trying to generate plain text. So no HTML, images or CSS is possible in my case.

EDIT 2: On the website linked, a Javascript function is used to convert the text

Here is the code :

function encool() {
    var _0xce74x20 = location[_0x804c[82]],
        _0xce74x21;
    if (_0xce74x20[_0x804c[84]](_0x804c[83]) == -1 && _0xce74x20[_0x804c[84]](_0x804c[85]) == -1 && _0xce74x20[_0x804c[84]](_0x804c[86]) == -1 && _0xce74x20[_0x804c[84]](_0x804c[87]) == -1 && _0xce74x20[_0x804c[84]](_0x804c[88]) == -1) {
        _0xce74x21 = document[_0x804c[91]][_0x804c[90]][_0x804c[89]]
    } else {
        _0xce74x21 = change(decomposeAString(document[_0x804c[91]][_0x804c[90]][_0x804c[89]]))
    };
    document[_0x804c[91]][_0x804c[92]][_0x804c[89]] = _0xce74x21
}

Pretty sure he is using a character mapping. I will look into that and post the solution if I find it.