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Returns the opacity of the whole window.

function glfwGetWindowOpacity(\GLFWwindow $window) : float

This function returns the opacity of the window, including any decorations.

The opacity (or alpha) value is a positive finite number between zero and one, where zero is fully transparent and one is fully opaque. If the system does not support whole window transparency, this function always returns one.

The initial opacity value for newly created windows is one.

  1. \GLFWwindow $window The window to query.

float The opacity value of the specified window.


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