Please note that the information in this section is only an overview of some of the important issues of which a game developer should be aware—it is the responsibility of the developer to ensure that they have the legal right to use assets in their game. Laws vary across states and countries, so be absolutely certain of your legal position prior to using any assets that you have not created yourself. In practice, it is always advisable to obtain written permission from a license holder, prior to using assets in a publicly released game.
The Internet is awash with freely available graphics and sounds assets. However, when an asset is freely available, it does not necessarily mean that the asset can be used legally!
Other than using assets that you have created yourself (or that your development team has created), the other main source of assets is the Internet. Prior to using any assets obtained from the Internet, it is important to understand some of the issues relating to copyright and licensing.
Although copyright is a very complex legal concept, the basics of copyright law are very easy to understand. Copyright gives the creator of a work the exclusive right to use that work. This means that only the creator of a work has the right to decide who can use that work and what they can use it for. When we refer to a work, in this context, we mean an original creation, examples of which include artwork, music, sounds, font designs, written text, and video games.
Although copyright laws vary between countries, most countries have very similar copyright laws. The main variations relate to the length of time for which copyright exists but, as a general rule, we can probably consider that for the purpose of game development, the types of asset that we will be using will almost always fall within those time limits and will, therefore, be subject to copyright laws.
There are very specific legal definitions of the phrase public domain, with variations that may apply in different jurisdictions. However, the principle is that, once copyright has expired, a work enters into the public domain, which means that it can be used for any purpose. Additionally, the creator of a work may voluntarily pass the work into the public domain, therefore forfeiting the right to determine future uses for that work.
When using public domain works in video games, it is important to ensure that they are actually in the public domain and not simply categorized incorrectly! For example, some websites contain libraries of freely available works, but they will not necessarily guarantee that the works are public domain.
There are many different forms of licensing available when using other people's assets in your game.
If the work is in the public domain, then no license is required.
If an asset that is not in the public domain is being used in your game, it is important to ensure that the licensing agreement for that asset is adhered to. For example, some creators of a work will allow the use of their creative work in any other work (such as a video game) as long as they are clearly attributed as the creator of the specific assets.
An example of this kind of licensing has been used for many of the assets that have been used in our game, Monkey Run! Most of the jungle graphics and objects used in the game were created by Vicki Wenderlich (www.vickiwenderlich.com), who has released the graphics under a Creative Commons Attribution license. Although there are several variations of the Creative Commons license, Vicki has chosen to allow free use of the images as long as she is clearly attributed as the original author. The only exception as specified on the licensing page on Vicki's website is that the art may not be sold by itself—it must form part of another work. For legal reasons, it is important to understand that this is my interpretation of the license—if you wish to use the graphics that Vicki has created, please do visit her website and read the license carefully! You will note that on the opening screen of our game, we have clearly displayed credits for the assets we have used, including the graphics and sound track. For more information about Creative Commons licenses, visit the website at www.creativecommons.org.
Google's Advanced Image Search, which can be found at www.google.com/advanced_image_search, is a very useful resource for locating images based on a type of license. For example, the following screenshot shows the Advanced Image Search being used to find images that are free to use, share, or modify, even commercially:
Another useful tool that provides searching by license type is www.iconfinder.com. Although, as its name suggests, this website is a resource for locating icons, many of the images can be used games as long as the license permits.
Very often, when searching for free assets to use in our games, we will find that the term royalty-free is used in an asset's description. It's important to understand that if an asset is royalty-free it doesn't necessarily mean that the asset is free to use!
A royalty is a fee that is paid to the license holder for each use of an asset. For example, if a copyrighted sound-track is used in a game, the license holder may require a fee to be paid for each copy of the video game that is sold. Depending on the size of the royalty fee and the numbers of products sold, the final amount to pay to the license holder could be quite substantial!
If an asset is royalty-free, it means that no royalty is paid for each use—however, a one off payment may be required to use the asset. As always, be sure to read the license agreement carefully, and take legal advice when required.
When collaborating in the creation of a game with other developers, artists, and musicians, it is important to have a written agreement relating to the use of assets that are created for the project. While it is easy to ignore such issues in the excitement of creating a new game, failure to have a formal agreement in place can lead to disagreements and even legal problems at a later stage.
Some questions to consider are:
Who legally owns each asset?
Can the asset be used in other projects? If so, then who can use it?
How will each contributor be rewarded for their work?
It's also important to ensure that ownership of the final product is determined before development work begins. Will each collaborator own an equal share of the work, or will some of the contributors receive a smaller or larger proportion of the rewards based upon their contribution to the project?
Ensure that these decisions are documented and agreed upon prior to starting development!
There is a lot of misunderstanding regarding the subject of copyright and licensing, and it's important to understand which assets can and cannot be used in your game. Following is a discussion of some of the common myths related to the use of game assets.
If a commercial game isn't available for sale anymore, I can use the game's assets in my own games.
If a game is no longer for sale, even if the publisher has gone out of business, copyright will probably still apply to those assets. Ownership of intellectual property (creative works) can be enormously complex, so never assume that game assets are available for use. The only sure way to know is to determine who has ownership of the assets, and then determine from the owner, in writing, whether or not the assets may be used in your games.
The graphics from an old, commercial game are freely-available on the Internet, which means that they are public domain.
Just because game assets are freely available on the Internet, it does not mean that they are free to be used for any purpose. Very often people will copy and share game assets under the misapprehension that they are doing so legally, and they may even state that the assets are free or public domain. Do not believe everything that you read on the Internet! Ensure that you are certain as to the provenance of the information before utilizing any free graphics that you obtain from the Internet.
I'm not making a profit from my game, so the owner of the copyrighted assets that I have used won't/can't take any legal action against me.
This is a very common myth! Although there are some intellectual property owners who are happy for others to use their assets for nonprofit purposes, it is very rare for such permission to be given. Most organizations take great care to protect their intellectual property, and are likely to employ lawyers to pursue legal action in the event that their intellectual property is used without permission.
I copied the assets from someone's game, but I've changed them a bit so no one can take legal action against me.
Changing someone's game assets prior to using them in your own games does not mean that copyright no longer applies. Some intellectual property owners will take legal action, even if there is the slightest resemblance to their copyrighted property. If a court decides that the modified works are too similar to the originals, or that some damage has been done to the public's perception of the owner of the original works, then financial damages are likely to be awarded.
There was no copyright information with the assets, so copyright laws don't apply to it.
In the vast majority of legal jurisdictions, copyright is implicit in all creative works. This means that copyright exists automatically when the work is created, and there is no legal requirement for the creator of a work to display a copyright notice. It is safest to assume that all works are copyrighted unless the legal owner of the intellectual property states otherwise!
I have some classical music on a CD, and it was composed hundreds of years ago, so it must be out of copyright and, therefore, I can use it in my game without permission.
Although there is a lot of classical music that is out of copyright, most of the recordings of that music are still under copyright! If you can perform out of copyright music yourself, and record it, then you can use it in your game!