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Sets the opacity of the whole window.

function glfwSetWindowOpacity(\GLFWwindow $window, float $opacity) : void

This function sets 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.

The initial opacity value for newly created windows is one.

A window created with framebuffer transparency may not use whole window transparency. The results of doing this are undefined.

  1. \GLFWwindow $window The window to set the opacity for.
  2. float $opacity The desired opacity 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