Awesome Gamedev

A curated list of good stuff related to the development of games. This list contains only free software for code, sellers who aren't evil for physical resources, and free cultural works for assets.

This is released under the GNU Free Documentation License - its text is provided in the LICENSE file.

Audio

Editors

• Audacity - Free software for recording and editing sounds. GNU GPLv2.
• MilkyTracker - Multi-platform application for creating .mod and .xm module files. GNU GPLv3
• Musagi - A large and sophisticated music editor. Expat.

Music

• Musopen - A site dedicated to copyright-free (and culturally free) music. Various licenses, all copyright-free (varies by piece).

Sound Effects

• Freesound.org - A collection of CC-licensed sound effects. Various licenses, all CC.
• SoundBible's Royalty-free section - A collection of CC or public-domain-licensed sounds. Various licenses, all CC or public domain.

Graphics

Assorted

This is a section for everything else that doesn't fit in some other graphics category.

• CanTree - Free online tree generator. Generates PNG files. Expat.
• Yobi3D - A search engine for 3D models that aims to display license information when possible. Various licenses, including free ones.

Collections

This category contains any 'grab-bags' of different kinds of art assets.

• Free stuff by 7Soul1 - A collection of various game-related assets. Available in PNG. Public domain.
• openclipart - A collection of various clip art. Available in PNG. Public domain.
• OpenGameArt.org - A large collection of art intended for game development. Various licenses, including free ones.
• Vecteezy - A collection of vector art. Various Creative Commons licenses.

Icons

• Game-icons.net - A constantly-growing collection of black-and-white icons. Available in SVG or PNG. CC-BY-3.0.

Sprites

• SpriteLib - A big collection of sprites. Available in PNG. CPL 1.0.

Graphics Tools

Bitmap Compression

• pngquant - A command-line utility for lossy compression of PNG images. Has various front-ends available. FreeBSD.
• Trimage- A cross-platform tool for losslessly optimizing PNG and JPG files. Expat.

Editors

• Blender - A 3D modelling and rendering editor. GNU GPLv2.
• GIMP - The GNU Image Manipulation Program. Designed for photo retouching, image composition and similar tasks. GNU GPLv3.
• Inkscape - A vector image editing program. GNU GPLv2.
• Krita - A digital painting and illustration program. GNU GPLv2.
• MakeHuman - A tool for making 3D characters. GNU AGPLv3.
• Overlap2D - An engine-agnostic game level and UI editor. Apache2.0.
• Tiled - Easy-to-use and flexible tile map editor. GNU GPLv2 and FreeBSD.

Spritesheet Tools

• Aseprite - Animated sprite editor and pixel art tool. GNU GPLv2.
• Piskel - Online pixel art and animated sprite creator. 'Do whatever you want' license.

Voxel Editors

• Sproxel - A 3D interface for quickly editing and creating voxel-based 3D models. 3-clause BSD.