On Thu, Jan 27, 2011 at 4:40 AM, bratliff <bratl...@umich.edu> wrote:
> On Jan 26, 1:23 pm, John Laur <johnl...@gmail.com> wrote: > > > Your response does reinforce though how much work it would be to > reimplement an ImageMapType equivalent -- we will hang tight and see what > happens on the issue tracker. > > You might find > > http://www.polylib.us/sparse > > http://www.polylib.us/sparsetile.js > > to be useful. It preceded ImageMapType overlay layers. > > I faced the same situation you have with too many zoom changes > happening in rapid succession. I solved it with deferred rendering. > I will be glad to extract the relevant pieces of code from PolyCluster > to incorporate in "sparsetile.js". Also, "sparsetile.js" is missing > the code to handle spanning of the International date line. > > For what it is worth, I believe aborting tiles in-flight & 50% > complete on average is not optimal. Instead, the tile ought to be > allowed to continue in an "IMG" element not attached to the DOM. A > perfectly good tile will be cached for future visits to the same zoom > level. It does not involve the overhead of aborting an http request. > No, the behavior you recommend is the cause of the slowness that John observes. > In conjunction, the API cannot dispatch all tile requests > immediately. A throttle or queue is required. It restricts the tiles > in flight simultaneously to some number like four. If the map > position changes, the queue is reprioritized to match the map > position. Tiles out of view are discarded. The tile's "onload" event > & "onerror" event are used to keep the pipeline flowing. It works > will with flight simulation where course corrections can occur > rapidly. > We have implemented tile queues in the past but they add significant latency to load a new viewport. "Optimal" depends on your goal. Most Maps API sites are not a flight simulator. -- > You received this message because you are subscribed to the Google Groups > "Google Maps JavaScript API v3" group. > To post to this group, send email to > google-maps-js-api-v3@googlegroups.com. > To unsubscribe from this group, send email to > google-maps-js-api-v3+unsubscr...@googlegroups.com<google-maps-js-api-v3%2bunsubscr...@googlegroups.com> > . > For more options, visit this group at > http://groups.google.com/group/google-maps-js-api-v3?hl=en. > > -- You received this message because you are subscribed to the Google Groups "Google Maps JavaScript API v3" group. To post to this group, send email to google-maps-js-api-v3@googlegroups.com. To unsubscribe from this group, send email to google-maps-js-api-v3+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-maps-js-api-v3?hl=en.
