[Openstreetmap] deagging interface

[SteveC]

* @ 19/10/05 02:46:35 PM lars at aronsson.se wrote:
> 
> > > > > > http://www.openstreetmap.org/edit/view-map2.html
> > > > > wow!
> 
> This new viewer is very nice, but there are some issues.

It's still beta, thanks for the bug reports :-)

> 1. When I recenter the map by double-clicking, the next zoom moves 
> to a different center point.

Double clicking is a known bug. It doesn't work in IE at the moment.

> 2. It is very slow.  Aren't tiles cached on the server?  The 
> zooming in and out seems to result in fixed levels of scale, e.g. 
> 0.703125, 0.17578125, 0.0439453125, 0.010986328125, 
> 0.00274658203125, 0.0006866455078125.  But I can also set (in the 
> URL) any arbitrary level of scale (e.g. 0.01000, 0.01001) and zoom 
> in and out from there, resulting in larger or smaller rounding 
> errors.  If tiles are cached at every arbitrary scaling level, 
> there would be no end to the storage need.

scale maps to a integer zoom level that (should) round off errors but it
might be mapping to a non-integer zoom level which would be bad.

Any WMS image requested is cached, simply.

As for speed, you should only see tiles taking time when they're being
rendered for the first time. Why is this slow? Because of three things,
in order of my estimate:

1) the NASA Landsat server can be very, very, very slow when the
americans wake up and start using it. And we backend to that for sat
imagery.

2) MapServer is a piece of junk which I've almost replaced.

3) SQL calls for loading some of the street data isn't totally optimised

have fun,

SteveC steve at asklater.com http://www.asklater.com/steve/