FL-Essentials (FLE) is a FLTK based software system which provides extreme easiness in building (responsive) GUI applications. It consists of C++ class library and gives thread-safe image processing support for OpenCV. It also provides OpenGL based 3D classes to create computer graphics applications with fully featured GUI.

Repository structure

FLE Library is implemented in C++ (but provides both a C and a C++ish interface). The directory structure is:



Take a look into the INSTALL file. The build system is CMake, if you already used CMake before there is a good chance you know what to do.

Video tutorial that explains the build procedure using CMake (three libraries OpenCV, FLTK, and FLE are compiled in this video):

How to Build OpenCV, FLTK, FL-Essentials using CMake

Required Libraries


Written by Dr. Furqan Ullah.

Reporting Bugs

Report bugs to drfurqan@users.noreply.github.com.


Copyright (c) 2017 Dr. Furqan Ullah.

See Also

Source code at: https://github.com/drfurqan/FL-Essentials.


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