Submitted my GUADEC paper last Friday, in time for the deadline. Although I finished it at 2am. It’s online here as a .tex and a .pdf, as well as a trivial plug-in that does very little, but does it reasonably correctly.
A couple of factual inaccuracies – shadow tiles have nothing to do with render speed as I say in the paper. It simply means that you are drawing on a copy of a tile, rather than the tile itself, and then all of the tiles get merged up to the “real” tiles in one, undoable, step. Otherwise, if we don’t use shadow tiles when drawing in a plug-in, and we cancel, we are drawing directly on the image’s tiles. Bad stuff.
Also, a consequence of marking tiles as not dirty, even if we are going to draw to them, is that the data for those tiles doesn’t get passed back to the core. This is interesting for multi-pass algorithms like Gaussian IIR, which is the application of a decomposable convolution matrix. So we have an intermediate drawable where we apply a horizontal vector, and on which we apply a vertical vector afterwards.
