NeoTextureEdit is an open source (GNU LGPL v. 3) easy to use graph-based procedural seamless texture editor. Using continuous basis functions it can generate arbitrary resolution images without quality degradation.
Substance Designer is a node-based non-destructive application for material authoring. Edit complete texture sets fast with the non-linear workflow and see your changes apply simultaneously to all your outputs.
Patternshop is a tool to create textures for fabric design.
It functions in a simple and intuitive way.
Import your images into the software and they will repeat instantaneously, adjust proportions, while you arrange them and work in real time.
Preview your work in real time,.
Texture Studio is all you need to produce professional quality textures for use in games and tiled backgrounds. Texture Studio includes a set of integrated tools, all extremely useful for creating high quality seamless textures.Discontinued
Alternative download available here https://sites.google.com/site/gibbagobba/downloads
Symbinode is an easy-to-use material creation program. The program is written in C++ and uses the power of the GPU. It is free and open source.
Symbinode vs TextureLab opinions
Symbinode is simple and powerful, allowing you to create any material with ease.