The Tesla 3D Engine is 100% open source and FREE to use for any type of project, may it be commercial or personal as long as you abide by the licensing terms. The software is available under the terms of the MIT license, which states the following:
Copyright (c) 2010-2013 Tesla 3D Engine - Nicholas Woodfield Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
Any content assets (e.g. artwork, logos, textures, audio, models, shaders) are further licensed under Creative Commons Attribution-Share Alike 3.0 , which states the following:
You are free: * To Share: to copy, distribute, display, and perform the work * To Remix: to make derivative works Under the following conditions: * Attribution - You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work). * Share Alike - If you alter, transform, or build upon this work, you may distribute the resulting work only under the same, similar or a compatible license. For any reuse or distribution, you must make clear to others the license terms of this work.The best way to do this is with a link to the above web page. Any of the above conditions can be waived if you get permission from the copyright holder. Apart from the remix rights granted under this license, nothing in this license impairs or restricts the author's moral rights.