Opened 15 years ago
Closed 15 years ago
#4801 closed defect (wontfix)
WMS doesn't work for Yahoo or Terraserver Urban when set to use UTM projection
| Reported by: | AM909 | Owned by: | team |
|---|---|---|---|
| Priority: | normal | Milestone: | |
| Component: | Core imagery | Version: | tested |
| Keywords: | WMS UTM projection NAD83 WGS84 | Cc: | AM909 |
Description
- In Preferences->Map Settings->Map Projection tab, set:
- Display... = Projected Coordinates
- Projection method = UTM
- UTM Zone 11
- Open "Jump to position" dialog with Ctrl-G and set (in this order)
- URL = http://www.openstreetmap.org/?lat=33.729197&lon=-118.076065&zoom=19
- Zoom (metres) = 26
- Create a new WMS layer with WMS->Terraserver Urban or WMS->Yahoo Sat.
Nothing but red error tiles are displayed.
I believe this is because of 2 issues:
- Looking at the query being sent, one problem appears to be the projection code parameter. It is sending "EPSG:325811" and there appear to be no such 6-digit codes. If I understand everything correctly, it seems that the correct code is EPSG:32611, which is WGS84 datum with UTM zone 11N projection*.
- The X values in the bounding box have an extra 3 at the beginning (X values in this area are in the 400000 range). Note that the coordinates displayed in the JOSM status bar at the bottom of the main window, as well as those displayed in the selection list dialog also have this spurious prefix.
* Note: The capabilities doc (http://msrmaps.com/ogccapabilities.ashx?version=1.1.1&request=getcapabilities&service=wms) shows that it only supports EPSG:4326 geographic projection, which uses the WGS84 datum, and EPSG:269xx UTM projections, which use the NAD83 datum.
However, it _does_ let you specify EPSG:32611, and the image returned is slightly different from that returned with EPSG:26911 - more difference than I would have expected from the very slight difference in the inverse flattening parameters of the two data (~0.000000086%). This expectation may not be correct, or there may be another problem - I'm out of time (at about 90 minutes so far).
EPSG:325811 ist EPSG:25811 with an additional 3000000 offset. It is e.g. used in germany for UTM zone 30. There are many additional projectsion missing and should be implemented.
The red tiles for Yahoo are correct and should correctly state that projection is wrong.
Missing capabilities request (and thus earlier projection tests) is another ticket already. Closing.