Misaligned broken KaMap tiles

[bbrehmer]

If you have a look at the attached screen shot you will see a valid tile (highlighted with firebug) and several broken (pink tiles). The broken tiles are offset in the X and Y direction and are broken because they are referencing an invalid path in the kamap generated cache.

Some other observations:

-All the broken tiles are always in the same row OR the same column

-The broken tiles always load after all the tiles in the viewport have loaded successfully. (ie. an extra row/column is loaded with broken tiles)

-So far I have been able to reproduce this bug in Firefox 2.0, IE 6, IE 7

In the meantime to not display broken pink tiles, I have added a fix to tile.php which returns a single pixel image if the specified image path deosn't exist.

[openlayers]

screen shot

[crschmidt]

If you could confirm this is still happening with 2.5, I'd appreciate it.

[openlayers]

Yes, this is still happening after updating to 2.5

[crschmidt]

Can you provide HTML which reproduces the problem? I haven't been able to get it to happen in my data. Also, the URL of a failing tile and the URL of a working tile alongside it would be good.

[bbrehmer]

I've created a sample page[1] based off the kamap.html example.

I've panned and zoomed around this sample page extensively but haven't been able to produce extra broken offset tiles.

One thing I did notice was that if OpenLayers.IMAGE_RELOAD_ATTEMPTS is set to some larger number (say 50) then IE comes back with a "Stack overflow at line: 0" message and one broken (pink) tile.

It deosn't seem as though this is related to the extra offset tiles since the one broken pink tile is aligned properly in the x & y direction but maybe a side effect?

I will continue to figure out a way to consistently reproduce the invalid extra offset tiles.

[1]  http://ben.simplymap.com/kamap.html

[bbrehmer]

I think this was a false alarm. After updating to 2.5 the broken images appearing are aligned properly in the x & y direction. Setting IMAGE_RELOAD_ATTEMPTS seems to alleviate the problem.