openlayers/openlayers — pull request #1305 by IvanSanchez (2014-04-15 14:33:14+00:00)
Title: DynamicCluster strategy

New clustering strategy, optimized for a lot of moving features.

Previously, if two features in a clustered layer were moving towards each other, they would never be clustered, and features inside a cluster would never get out of it. Unless all the clusters for all the features (included the ones off-screen) were recalculated, which was taking stupidly high amounts of CPU.