= class Gdk::Window

== Object Hierarchy
* Object
  * GLib::Instantiatable
    * GLib::Object
      * Gdk::Drawable
        * Gdk::Window

== Instance Methods
--- gl_capable?
    ((*Ruby/GtkGlExt*)) Returns whether the window is OpenGL-capable.
    * Returns: true if the window is OpenGL-capable, false otherwise.

--- gl_drawable
    ((*Ruby/GtkGlExt*)) Returns the Gdk::GLDrawable held by the window. In fact, this is a macro that casts the result of Gdk::Window#gl_window to Gdk::GLDrawable.
    * Returns: the Gdk::GLDrawable.

--- gl_window
    ((*Ruby/GtkGlExt*)) Returns the Gdk::GLWindow held by the window.
    * Returns: the Gdk::GLWindow.

--- set_gl_capability(glconfig)
    ((*Ruby/GtkGlExt*)) Set the OpenGL-capability to the window. This function creates a new Gdk::GLWindow held by the window.
    * glconfig: a Gdk::GLConfig.
    * Returns: the Gdk::GLWindow used by the window if it is successful, nil otherwise.

--- unset_gl_capability
    ((*Ruby/GtkGlExt*)) Unset the OpenGL-capability of the window. This function destroys the Gdk::GLWindow held by the window.
    * Returns: self