/// <summary>
/// Sets the special keyboard up (key release) callback for the current window.
/// </summary>
/// <param name="func">
/// The new special keyboard up callback function.
/// <see cref="SpecialUpCallback" />.
/// </param>
/// <remarks>
/// <para>
/// <b>glutSpecialUpFunc</b> sets the special keyboard up (key release) callback
/// for the current window. The special keyboard up callback is triggered when
/// keyboard function or directional keys are released. The <i>key</i> callback
/// parameter is a GLUT_KEY_* constant for the special key pressed. The <i>x</i>
/// and <i>y</i> callback parameters indicate the mouse in window relative
/// coordinates when the key was pressed. When a new window is created, no
/// special up callback is initially registered and special key releases in the
/// window are ignored. Passing <c>null</c> to <b>glutSpecialUpFunc</b> disables
/// the generation of special up callbacks.
/// </para>
/// <para>
/// During a special up callback, <see cref="glutGetModifiers" /> may be called to
/// determine the state of modifier keys when the key release generating the
/// callback occurred.
/// </para>
/// <para>
/// To avoid the reporting of key release/press pairs due to auto repeat, use
/// <see cref="glutIgnoreKeyRepeat" /> to ignore auto repeated keystrokes.
/// </para>
/// <para>
/// An implementation should do its best to provide ways to generate all the
/// GLUT_KEY_* special keys. The available GLUT_KEY_* values are:
/// </para>
/// <para>
/// <list type="table">
/// <listheader>
/// <term>Value</term>
/// <description>Description</description>
/// </listheader>
/// <item>
/// <term><see cref="GLUT_KEY_F1" /></term>
/// <description>F1 function key.</description>
/// </item>
/// <item>
/// <term><see cref="GLUT_KEY_F2" /></term>
/// <description>F2 function key.</description>
/// </item>
/// <item>
/// <term><see cref="GLUT_KEY_F3" /></term>
/// <description>F3 function key.</description>
/// </item>
/// <item>
/// <term><see cref="GLUT_KEY_F4" /></term>
/// <description>F4 function key.</description>
/// </item>
/// <item>
/// <term><see cref="GLUT_KEY_F5" /></term>
/// <description>F5 function key.</description>
/// </item>
/// <item>
/// <term><see cref="GLUT_KEY_F6" /></term>
/// <description>F6 function key.</description>
/// </item>
/// <item>
/// <term><see cref="GLUT_KEY_F7" /></term>
/// <description>F7 function key.</description>
/// </item>
/// <item>
/// <term><see cref="GLUT_KEY_F8" /></term>
/// <description>F8 function key.</description>
/// </item>
/// <item>
/// <term><see cref="GLUT_KEY_F9" /></term>
/// <description>F9 function key.</description>
/// </item>
/// <item>
/// <term><see cref="GLUT_KEY_F10" /></term>
/// <description>F10 function key.</description>
/// </item>
/// <item>
/// <term><see cref="GLUT_KEY_F11" /></term>
/// <description>F11 function key.</description>
/// </item>
/// <item>
/// <term><see cref="GLUT_KEY_F12" /></term>
/// <description>F12 function key.</description>
/// </item>
/// <item>
/// <term><see cref="GLUT_KEY_LEFT" /></term>
/// <description>Left directional key.</description>
/// </item>
/// <item>
/// <term><see cref="GLUT_KEY_UP" /></term>
/// <description>Up directional key.</description>
/// </item>
/// <item>
/// <term><see cref="GLUT_KEY_RIGHT" /></term>
/// <description>Right directional key.</description>
/// </item>
/// <item>
/// <term><see cref="GLUT_KEY_DOWN" /></term>
/// <description>Down directional key.</description>
/// </item>
/// <item>
/// <term><see cref="GLUT_KEY_PAGE_UP" /></term>
/// <description>Page up directional key.</description>
/// </item>
/// <item>
/// <term><see cref="GLUT_KEY_PAGE_DOWN" /></term>
/// <description>Page down directional key.</description>
/// </item>
/// <item>
/// <term><see cref="GLUT_KEY_HOME" /></term>
/// <description>Home directional key.</description>
/// </item>
/// <item>
/// <term><see cref="GLUT_KEY_END" /></term>
/// <description>End directional key.</description>
/// </item>
/// <item>
/// <term><see cref="GLUT_KEY_INSERT" /></term>
/// <description>Insert directional key.</description>
/// </item>
/// </list>
/// </para>
/// <para>
/// Note that the escape, backspace, and delete keys are generated as an ASCII
/// character.
/// </para>
/// </remarks>
/// <seealso cref="SpecialUpCallback" />
/// <seealso cref="glutButtonBoxFunc" />
/// <seealso cref="glutGetModifiers" />
/// <seealso cref="glutIgnoreKeyRepeat" />
/// <seealso cref="glutKeyboardFunc" />
/// <seealso cref="glutKeyboardUpFunc" />
/// <seealso cref="glutMouseFunc" />
/// <seealso cref="glutSpaceballButtonFunc" />
/// <seealso cref="glutSpecialFunc" />
/// <seealso cref="glutTabletButtonFunc" />
// GLUTAPI void APIENTRY glutSpecialUpFunc(void (GLUTCALLBACK *func)(int key, int x, int y));
public static void glutSpecialUpFunc([In] SpecialUpCallback func) {
specialUpCallback = func;
__glutSpecialUpFunc(specialUpCallback);
}
private static extern void __glutSpecialUpFunc(SpecialUpCallback func);
