[OpenLayers-Trac] [OpenLayers] #933: Animated transition between views

[OpenLayers]

#933: Animated transition between views
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  Reporter:  openlayers       |       Owner:  pspencer                
      Type:  feature          |      Status:  new                     
  Priority:  minor            |   Milestone:  2.6 Release             
 Component:  general          |     Version:  SVN                     
Resolution:                   |    Keywords:  animated transition time
     State:  Needs More Work  |  
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Comment (by tschaub):

 Ok, I think this is in good shape.  A couple more changes (and way too
 many hours debugging):

  1. The ratio != 1 bit was not a good check for "resolutions changed" or
 "zoomed."  Imagine a scenario where you zoom in (ratio == 2) and then you
 zoom back out (ratio == 1).  So, with the ratio != 1 check the buffer
 tiles were not properly resized and placed when you returned to the
 original resolution (ratio == 1).  By giving tiles a lastRatio property
 (could do this whole thing in a control with it's own grid to avoid
 extending tiles so much), we can check if a change in resolution actually
 occurred (ratio != lastRatio) and resize/reposition accordingly.
  1. There were a number of hide/show sequences that didn't appear to be
 necessary (could have been efforts to get rid of the flicker?)
  1. The flicker looks to be the same issue we just had with SVG flicker
 ([http://trac.openlayers.org/ticket/1390#comment:10 my take]).  It looks
 like Firefox does not reflow in a predictable way when in a sequence of
 code triggered by a browser event.  In this case, image load triggers our
 tile "loaded" event (or layer "loaded") and we try to show the main tile
 before hiding the buffer tile.  This sequence is not always respected.
 The solutions are to continue execution in a separate thread
 (window.setTimeout(func, 0)) or to set some other dom property (without
 actually changing it).  As with #1390, I think this is best done with the
 simple property reset hack.  This means that tile.show gets a check for
 gecko and does the hack to force a reflow before the buffer tile is
 adjusted.

 I updated the example and played around with it for a bit.  All looks good
 on Firefox.

 The Tween tests (2 of them) are failing.  I'm not going to take that on
 right now.

 If someone fixes the Tween tests and confirms that this performs as
 expected, I think it's good to go.

-- 
Ticket URL: <http://trac.openlayers.org/ticket/933#comment:17>
OpenLayers <http://openlayers.org/>
A free AJAX map viewer