TUTORIAL Race Track Builder - Inject elevation data and terrain texture

[Wurstkoffer]

Response from WMS will be slower than from google, but it shouldn't deliver zeros, if the requested location is within it's coverage (Saxony, Germany in my example code - https://www.google.com/maps/place/Saxony/).
Google should always deliver, coze it's coverage contains the whole world.

I assume, you replaced "MYAPIKEY" with your api key? What errors you get when you click the WMS und Google links in logfiles?

 

[Les Neilson]

Yes, I put MYAPIKEY to hide my real one. I was using the example location from your original config.php. The API key was the only thing I changed in it. On the localhost page everything seemed okay, and the elevation was 517, I think. I won't be back at my pc until sunday night, so for now I can't look at the log files

 

[Les Neilson]

This is what my log file looks like:

 

[Wurstkoffer]

Click the links above some json errors and paste the response here.

 

[Les Neilson]

Okay, this is what I see...

...which seems okay

 

[Wurstkoffer]

Hm yeah, looks good. Change the following in config: ini_set('display_errors', 1). And please send the log file as attatchment.

 

[Les Neilson]

Okay, here they are:

I appreciate you taking the time to help me out: I really would like to use this. I've been over the instructions again carefully, but I can't see anything I've missed. Should I look again at the steam page where you also posted this?

 

[Wurstkoffer]

I think i found the problem. There is a space or %20 in front of your API key. Delete that in RTB Settings.

 

[Les Neilson]

Okay, let me give that a try...

 

[Les Neilson]

Cool! It's working! Thank you so much..

 

[Wurstkoffer]

Nice

 

[Les Neilson]

Any chance you could give any tips on how to extract the necessary info from a WMS server to modify config.php? (maybe using QGis to search the various layers?) For example I've been looking at this site:

https://eo.jncc.gov.uk/geoserver/scotland/wms?service=wms&version=1.3.0&request=GetCapabilities
https://eo.jncc.gov.uk/geoserver/scotland/wms?service=wms&version=1.3.0&request=GetCapabilities
I can figure out how to find the elevation values, but there's no ortho layer as far as I can see. Can I leave it blank?

Thanks once again...

 

[Les Neilson]

I would replace it with a Google Maps image in any case, probably

 

[Wurstkoffer]

yeah, leave it blank and ...

$wms_orto_fetch = false;

I'm not sure how the config test page behaves. I've only ever tested it, i think, with ortho fetch from WMS enabled.

 

[Les Neilson]

It's almost working, but look at this screenshot

The problem is there's no end string to the elevation value, so it doesn't pick up the value correctly. I tried putting something from the following line, but it doesn't seem to be working. Any ideas?

 

[Wurstkoffer]

hmmm, try "\n" as end string. it stands for line break.

 

[Les Neilson]

Thanks again, it seems to be working now... On to the next problem I'm getting a lot of negative numbers outside of the sampled area (-9999) Where in the code can I limit the elevations to zero? (or only slightly negative)

 

[Wurstkoffer]

Oh, apparently the WMS server you're using provides extreme values outside the covered area. The WMS server from my example returned NULL values there. Therefore, the script decides: If WMS does not return a value - take the value from Google. I'll check it out and get back to you.

 

[Wurstkoffer]

Can't reproduce this behaviour. I set up the elevation part in my config as follows:

$wms_elevation_url = "https://eo.jncc.gov.uk/geoserver/scotland/wms?";
$wms_elevation_layer = "scotland-lidar-2-dtm";
$wms_elevation_querylayers = "scotland-lidar-2-dtm";
$wms_elevation_format = "text/plain";
$wms_elevation_response_start_str = "GRAY_INDEX = ";
$wms_elevation_response_end_str = "\n";

... didn't changed the LAT/LON so it requested the location from my example (Saxony, Germany). The Scotland WMS delivered "no features were found". I now remember, the script validates if the response is a number. So in this case, no number is delivered. Therefore the Google value will be used and sent to RTB, as you can see in the screenshot.

 

[Les Neilson]

The elevation url line I use is

$wms_elevation_url = "https://eo.jncc.gov.uk/geoserver/scotland/wms?service=wms&version=1.3.0&request=GetCapabilities";