On Wed, Nov 28, 2012 at 02:26:56PM +0100, Stephan Houben wrote: > Apart from introducing a bounding box check, I would > suggest converting each scanline into a single exact integer > with 1 bits corresponding to alpha unequal 0. Then for each scanline, > you can use arithmetic-shift and bitwise-and, and then check the result for > being non-zero. > > Stephan
When the situation gets intense (i.e., lots and lots of objects) one of the big wins is not even to prefilter with bounding boxes, but to find ways of sorting objects by location (bearing in mind they aren't point masses) and managing never to even consider objects that are nowhere near each other. Sometimes the most efficient way to accomplish something is not to do it. -- hendrik ____________________ Racket Users list: http://lists.racket-lang.org/users
