imagettftext() does not properly render combining chars

Description

I'm forwarding this from the ancient https://bugs.php.net/34670; I had reported that a couple of years ago upstream (https://github.com/libgd/libgd/issues/758), where the ticket had been closed as WONTFIX; however, that was a week after libgd 2.3.3 had been released, which has optional support for libraqm, which solves the issue, as I found out while investigating on https://github.com/libgd/libgd/issues/861.

The following code:

<?php
$im = imagecreatetruecolor(64, 32);
imagefilledrectangle($im, 0, 0, imagesx($im) - 1, imagesy($im) - 1, 0x000000);
imagettftext($im, 16, 0, 10, 20, 0xffffff, "Arial", hex2bin("c3a461cc88"));
imagegif($im, __DIR__ . "/out.gif");

Resulted in this output (bundled libgd):

But I expected this output instead (libgd 2.3.3 with libraqm):

So to solve this for our bundled libgd, we would need to add support for libraqm (probably that wouldn't be a big deal, if especially gdft.c hadn't been diverged between bundled and external libgd, and I believe there are a couple of important fixes only in bundled libgd). For Windows users, we would also need to build and ship libraqm and its dependencies (at least harfbuzz in this case).

PHP Version

any

Operating System

any

Bắt đầu với triển khai gdft.c đi kèm và tái hiện ví dụ PHP được cung cấp bằng một ký tự kết hợp. So sánh đầu ra của nó với libgd 2.3.3 được cấu hình với libraqm, sau đó xác định các yêu cầu về tích hợp và dependency trên Windows. Hoàn thành có nghĩa là imagettftext() kết xuất chính xác các ký tự kết hợp bằng libgd đi kèm trên tất cả các build được hỗ trợ.