Allan Brito has published a mini-tutorial on how to use FreeStyle rendering in the current 2.50 builds.
Allan writes:
The integration between Blender 3D and FreeStyle render, which is capable of create great NPR images is one of the features develop as part of the SoC 2008. It is still in development by Maxime Curione, but now the development is aimed to use FreeStyle with Blender 2.50. This a useful feature for architectural visualization artists, especially if you don’t want to make presentations using realistic renders. With FreeStyle we can create animations and renderings with a cartoon or sketch style.
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