Bad rendering at zoom level 1

[sbenthall]

Zoom out to one zoom level and watch the vector rendering go bad. It looks like everything is proportionally distanced from each other as it should, which makes me think that the problem is in the resolution the renderer is using.

I checked to make sure the renderer resolution cache is being reset when it should be. and it appears that that all works.

My best guess now is that the base layer's getResolution method is returning an incorrect number for some reason.

[sbenthall]

From duplicate ticket #380

"The notes WFSV Layer seems to have precision problems between zoom levels whereby OL does not shift the features to the correct location on refresh so they start to "walk" from their initial, correct, position.

To reproduce,

1. Pick any notes popup feature and note its location to a nearby road 2. Zoom in one level, and notice its new spatial location in relation to the previous road ... its moved :) "

[sbenthall]

I've traced this to what I believe to be a GeoServer? error on GeoServer? instance that we have been hitting for this development.

http://jira.codehaus.org/browse/GEOS-2345

When I pointed the base layer towards another geoserver instance, the problem appears to go away.

Chris, I'm not sure if you are rendering the base layer locally or using one of our servers. Let me know if you are doing the former, as it will give us a reason to prioritize that ticket.

[sbenthall]

I've been informed that since this bug isn't on the contract, I need to make it lower priority.

[arneke]

The problem is that the bounds don't line up to the "world wide grid" used for EPSG:900913 on the tiling server.

OpenLayers uses, when not provided with anything else to determine grid layout, maxextent. The values in the current configuration do not line up with the grid.

To make it work nicely you should set maxextent to -2.003750834E7,-2.003750834E7,2.003750834E7,2.003750834E7 or another aligned value, such as -8296780.797031253,4852834.05109375,-8140237.763125002,5009377.085 but either one will zoom you out quite a bit.

So to fix that, Vespucci needs one more parameter, something that zooms to bounds that are not maxextent:

map.zoomToExtent(new OpenLayers.Bounds(-8267550.218915735,4935088.796356421,-8205620.439273276,5000571.233491));

For an example, please have a look at the (trivial) source code of http://geo.openplans.org:8080/geoserver/gwc/demo/topp:nyc_background?srs=EPSG:900913

[sbenthall]

Fixed r815

Thanks, Arne.