Skip to content


This function sets the character callback of the specified window, which is called when a Unicode character is input.

function glfwSetCharCallback(\GLFWwindow $window, callable $callback) : void


glfwSetCharCallback($window, function($codepoint) {
    echo "Character: " . mb_chr($codepoint) . PHP_EOL;

The character callback is intended for Unicode text input. As it deals with characters, it is keyboard layout dependent, whereas the key callback is not. Characters do not map 1:1 to physical keys, as a key may produce zero, one or more characters. If you want to know whether a specific physical key was pressed or released, see the key callback instead.

The character callback behaves as system text input normally does and will not be called if modifier keys are held down that would prevent normal text input on that platform, for example a Super (Command) key on macOS or Alt key on Windows.

  1. \GLFWwindow $window The window whose callback to set.
  2. callable $callback



This documentation page is prased from the glfw3.h header file, and only modified to fit the PHP-GFLW extension bindings. The original documentation copyright is as follows:

Copyright (c) 2002-2006 Marcus Geelnard
Copyright (c) 2006-2019 Camilla Löwy