This manual describes the Fast Light Tool Kit ("FLTK") version 1.1.10, a C++ Graphical User Interface ("GUI") toolkit for UNIX, Microsoft Windows and MacOS. Each of the chapters in this manual is designed as a tutorial for using FLTK, while the appendices provide a convenient reference for all FLTK widgets, functions, and operating system interfaces.

This manual may be printed, modified, and/or used under the terms of the FLTK license provided in Appendix A.


This manual is organized into the following chapters and appendices:


The following typeface conventions are used in this manual:


The following abbreviations are used in this manual:

The X Window System version 11.
The X Window System interface library.
The Microsoft Windows 32-bit Application Programmer's Interface.
The Apple Macintosh OS 8.6 and later, including OS X.

Copyrights and Trademarks

FLTK is Copyright 1998-2009 by Bill Spitzak and others. Use and distribution of FLTK is governed by the GNU Library General Public License, located in Appendix H.

UNIX is a registered trademark of the X Open Group, Inc. Microsoft and Windows are registered trademarks of Microsoft Corporation. OpenGL is a registered trademark of Silicon Graphics, Inc. Apple, Macintosh, MacOS, and Mac OS X are registered trademarks of Apple Computer, Inc.