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Returns whether the specified extension is available.

function glfwExtensionSupported(string $extension) : int

This function returns whether the specified API extension is supported by the current OpenGL or OpenGL ES context. It searches both for client API extension and context creation API extensions.

A context must be current on the calling thread. Calling this function without a current context will cause a GLFW_NO_CURRENT_CONTEXT error.

As this functions retrieves and searches one or more extension strings each call, it is recommended that you cache its results if it is going to be used frequently. The extension strings will not change during the lifetime of a context, so there is no danger in doing this.

This function does not apply to Vulkan. If you are using Vulkan, see @ref glfwGetRequiredInstanceExtensions, vkEnumerateInstanceExtensionProperties and vkEnumerateDeviceExtensionProperties instead.

  1. string $extension The ASCII encoded name of the extension.

int GLFW_TRUE if the extension is available, or GLFW_FALSE otherwise.


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