During the last two weeks, the dev team was working on support for full sample anti-aliasing. At the moment, full sample anti-aliasing does not work well with Freestyle. Strokes are drawn only in one of multiple samples, which results in very faint strokes in the final anti-aliased render. The full sample anti-aliasing issue has been demanding a considerable amount of code reading with regard to the render pipeline of Blender’s internal renderer, and so far no major coding has been done. A proper implementation of full sample anti-aliasing for Freestyle seems a non-trivial task due to the complexity of the render pipeline. The internal renderer is multithreaded through a tile-based data decomposition in which an image to be rendered is split into a two-dimensional grid of tiles. Each tile is a small portion of the entire image, and multiple threads work on different tiles in parallel. When full sample anti-aliasing is enabled, the render pipeline also involves external file I/O in the EXR image format. These implementation details make it difficult to enhance the internal renderer so that full sample anti-aliasing works properly with Freestyle. We will further look into this issue in the next weeks.
March 14, 2010
Weekly update March 2-14