this path contains the excellent µgui library from achim döbler.
this code can be obtained from github.com/achimdoebler/UGUI. the license follows.
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/* -- µGUI - Generic GUI module (C)Achim Döbler, 2015 -- */
/* -------------------------------------------------------------------------------- */
// µGUI is a generic GUI module for embedded systems.
// This is a free software that is open for education, research and commercial
// developments under license policy of following terms.
//
// Copyright (C) 2015, Achim Döbler, all rights reserved.
// URL: http://www.embeddedlightning.com/
//
// * The µGUI module is a free software and there is NO WARRANTY.
// * No restriction on use. You can use, modify and redistribute it for
// personal, non-profit or commercial products UNDER YOUR RESPONSIBILITY.
// * Redistributions of source code must retain the above copyright notice.
//
/* -------------------------------------------------------------------------------- */
/* -- MY SPECIAL THANKS GO TO -- */
/* -------------------------------------------------------------------------------- */
// Andrey Filimonov (-->https://github.com/Sermus)
// for giving valuable suggestions, reporting bugs and adding several new features.
// Andrey also put a lot of work in the implementaion of anti-aliased font support.
//
// Mikhail Podkur (-->https://github.com/MikhailPodkur)
// for adding cyrillic 8x12 font, checkbox feature and RGB565 support.
//
// Gustavo Denardin
// for giving valuable suggestions regarding real-time os support.
//
// Samuel Kleiser
// for reporting bugs and giving examples how to improve µGUI.
/* -------------------------------------------------------------------------------- */
/* -- REVISION HISTORY -- */
/* -------------------------------------------------------------------------------- */
// Dec 20, 2015 V0.31 Checkbox component with all funtions added.
// Cyrillic font 8x12 added.
// RGB565 color schema added.
// Windows components font could be getted from current GUI by default
// Mar 18, 2015 V0.3 Driver support added.
// Window and object support added.
// Touch support added.
// Fixed some minor bugs.
//
// Oct 20, 2014 V0.2 Function UG_DrawRoundFrame() added.
// Function UG_FillRoundFrame() added.
// Function UG_DrawArc() added.
// Fixed some minor bugs.
//
// Oct 11, 2014 V0.1 First release.
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