Font-Render-Tester is a tool that shows previews of text in a given font and different settings. It supports font features like font size and font variations (font width, weight, etc.). You can also turns on and off OpenType shaping to see how the give text would render with specific OpenType settings like direction, script and language.
Font-Render-Tester also shows some of the basic font metrics information like Ascend or Decend.
Also, you can change fonts imediately from the list make it's quite useful to preview differnt font files.
Font-Render-Tester is written in modern C++ and uses FreeType2 for glyph rendering and Harfbuzz for OpenType shaping.
On my personal website, I'm maintaining a small list of games that support Thai and how they perform in that regards. I need to create screenshot to shows how Thai text should looks like comparing to the actual text in game. At first I was using Microsoft Word for that task. Later on I wants to learn more on how to properly implement the text rendering so I created my own tool.
Also in my game engine, I need to specify the settings of the font metrics I'm using instead of reading the value from the font file. Since the tool can shows some basic font metrics value, I can use this to choose the font I'm going to use along with its metrics values.
At the first run, the application works on its own font directory (the one used on the GUI). You can
change the font directory by choose menu File->Change font directory.
Once the font directory is set you can start playing with the toolbar on the right hand side.
You can play with OpenType text shaping, either enable or disable. For my use I usually uses it to find if font can render Thai correctly when either text shaping is off or on, and when it's on does it need the specific algorithm for the language or not.
You can also change the text direction in certains lanuage, like vertical text in Japanese.
Notes: screenshot contains lyrics from the song Sakura Iro Mau Koro by Mika Nakashima ℗2005 Sony Music Labels Inc.
For variable fonts, you can change any of the 5 common axis, depends on whether or not the axis is supported by the given font.
Notes: screenshot contains lyrics from the song [Slow Dancing in a Burning Room by John Mayer(https://www.youtube.com/watch?v=5MkfBNl_3pw) ℗2006 Aware Records LLC.
