General

• If you are submitting an art asset, you must upload the whole art asset in a usable form.
• We cannot accept watermarked submissions (audio, image, or otherwise), as watermarks render the content unusable on its own.
• Specifically, if someone must go to a different website to obtain a usable version of your submitted work, we cannot accept it (however, it is perfectly fine to request that someone go to your website).
• OGA reserves the right to remove 'trivial' submissions -- that is, something that could easily be produced by anyone in a very short amount of time.
• OGA reserves the right to combine groups of small, similar submissions by the same author in order to keep the archive organized.
• Your title and preview images must be descriptive of the content you actually uploaded.  Specifically, if what you uploaded is a sample of a larger pack, the preview image must describe the art you actually uploaded to OGA, and not the additional art that you are advertising.  It is fine to link to the larger pack in your description.

Copyright and Trademarks

• OGA cannot accept content that the owner has not explicitly released under one of the available licenses.
• OGA cannot accept derivative works of content that has not been explicitly released under one of the available licenses, with the exception that you can create a derivative of a work with a CC 2.0 license and release it under the equivalent 3.0 license, provided you maintain the author's credit.
• Derivative works include things like fan art.  Even if you made the art entirely on your own, if the subject of the art doesn't belong to you, it's still a derivative work.  If you create a 3D rendition of Mario, for instance, that's still a derivative of Nintendo's intellectual property, and we cannot accept it here.
• If there could be any reasonable debate over whether something is a derivative work, OGA cannot accept it.
• OGA cannot accept art that contains registered trademarks, unless you can provide proof that the owner of that trademark has specifically licensed it in a way that complies with the art license you choose (they probably haven't -- in fact, it's likely that it might negate the trademark).
• OGA's purpose is not to fight battles over what constitutes fair use and what doesn't -- people downloading the media on OGA need to be certain that it won't cause any copyright problems.  If something is based on a copyrighted work that you don't have a license to use, do not submit it, even if you happen to disagree with the way copyright law is written, applied, or enforced.

Concept Art

• Since the purpose of concept art is to convey an idea, we're not putting any restrictions on concept art except that it convey an original, game-appropriate concept.
• The usefulness of concept art will be weighed more heavily if the art is being used as an advertisement by the artist.  The idea of the loose guidelines in this category isn't to give people a place to dump art that's not really usable -- it's to allow people to post legitimate concept art. :)

2D Character Art

• Character portraits and other character art should be released in a non-lossy format with a transparent background.  The easiest way to do this is use PNG.
• There shouldn't be any evidence of pencil lines in the finished product unless that's the intended style of the work.  Use your pencil sketch as a guide to paint over, then hide the pencil layer before you save the image.
• 2D character art should generally not just be a render of a 3D model, unless the model is already available on the site.

2D Background Art

• PNGs are preferred, but not required.
• Make sure the your art is clean.  As above, if pencil lines aren't part of the art style, be sure to paint on a separate layer and hide them when you're finished.

Music

• Music tracks should be encoded in a high quality format, with a 128kbps MP3 bare minimum.  We prefer OGG or FLAC, as these are higher quality than MP3 and aren't encumbered by patent licensing issues.
• The first preview file should be an audio file, not a graphic. It is acceptable to also include album art on your music submission, but the first preview is displayed in the site's gallery, so it should be something users can hear. That way they can get an idea of what kind of music is being shared.
• For size considerations, please don't upload WAVs of long music tracks.  If you prefer to release your music in a non-lossy format, use FLAC.
• If you are using software to compose your music and you can export a MIDI file, that would be a bonus.
• Volume should be normalized so the music is audible at a typical volume but no clipping occurs.

Sound Effects

• Short sound effects should be released in WAV or FLAC format.  Longer sound effects are acceptable in high quality MP3 or OGG.
• The first preview file should be an audio file, not a graphic. It is acceptable to also include graphics that help convey the sound effect's purpose, but the first preview is displayed in the site's gallery, so it should be something users can hear. That way they can get an idea of what kind of sound effect is being shared.
• Volume should be normalized so the music is audible at a typical volume but no clipping occurs.

Textures

• Loss-less formats are preferred for small textures (1024x1024 or less), but it's okay to use JPGs for particularly large textures.  Please keep the JPG quality high enough to avoid visible artifacts.
• If you're posting photographed textures, it's best to take pictures on an overcast day, because that provides an even, white light without casting obvious shadows.
• If you're making a tiling texture, use a high pass filter to avoid vignetting and brightness variation in your photos.

3D Art

• YOU MUST CREDIT YOUR TEXTURES.  If you don't know where your textures came from, we cannot use them.
• On the subject of textures, we can't accept any textures that come from CGTextures or sites with similar licensing restrictions.  All textures used in your work must be available under one of OGA's allowed licenses.  For legal reasons, we can't make exceptions to this under any circumstances.

Documents

• The documents category is for anything that doesn't currently fit into the other categories.  At this time, the only restriction on documents is that they must be usable in a game on their own.  We may refine and update these guidelines as more documents are submitted.

Art tags

Check out this guide for effective art tagging: https://opengameart.org/content/art-tags

You want tags to help people find your art. If the tag is a word or phrase people have never seen before, they won't know to search for it. Be sure each tag is...

• short and concise
• spelled correctly
• not redundant (things like "game", "3D", "art", "music", "2D", "free", "asset" don't really narrow down the search any)
• words that a reasonable person would know already.
• don't use hashtags (#)
• separated with a comma (,) not just a space or a period.