optimizePanAnimation. It was a single bullet point in a long list so a follow-up post was in order to explain why we added it and what it does.
map.centerAt() was used to pan the map large distances when the map was at medium to large scales (think zoom level 10 and greater). Calling
centerAt() was causing the map to request and load hundreds of tiles to accommodate the default map pan animation. As I’m sure you’ve guessed, loading hundreds of tiles is slow and in turn makes the map look and feel slow. Using
map.setExtent() could have the same result if the new extent does not cause a zoom level change.
To address this, we decided to add a configuration option to the map. We threw around a few different names, I suggested
abuseTiledServices but that seemed a little too opinionated. We settled on
optimizePanAnimation and made it true by default. If you’d like to get the pre-3.7 behavior back because you or your users prefer the pan animation as it provides some orientation of where the map is going, use
optimizePanAnimation: false when you create a map.
To really drive home the difference this makes, I’ve put together two demo pages: one to show a map with optimizePanAnimation set to true and the same page with optimizePanAnimation set to false. Try both by clicking the city names in the side bar to see the difference in time it takes to move between cities and how many tiles are loaded in each case.