Please run
git clone --recursive https://github.com/ComputerNerd/Retro-Graphics-Toolkit
to checkout the repository.
Retro Graphics Toolkit is a free software (open source) graphics converter, tilemap, blocks, chunks, sprites and level editor. The goal is to make the task of taking an image and converting it to tiles on a tilemap or sprite sheet into many sprites as easy as possible. Also easy chunk editing, block importing from an image. Retro Graphics Toolkit supports many advanced features that many popular graphics editing program support such as undoing and redoing and project files. Retro Graphics Toolkit is also extensible with Lua scripting support.
The compiling instructions are in the file COMPILE.
Retro Graphics Toolkit only needs FLTK and Lua installed. GNU/Linux users may use their system package manager to install these depending on the distribution.
Retro Graphics Toolkit is licensed under the terms of GPL v3 or later. This can be found in the file called COPYING. Any example code that is part of the Retro Graphics Toolkit project is licensed under a one clause BSD style license. This means anything only in the folders called examples and luaExamples all other code is licensed under the terms of the GPLv3 license or later. If you unsure what is part of the Retro Graphics Toolkit project it is anything that the base url (as of writing) is: https://github.com/ComputerNerd/Retro-Graphics-Toolkit If you are still unsure just ask. Here is the license used by example code
Copyright (c) 2014-2015, Sega16 All rights reserved.
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
In other words if you use the sample code in your project that is fine, but don't say I made your project. I would not object to and in fact I would encourage that you say something to the effect of this uses sample code from the Retro Graphics Toolkit project.