Ade-gp 0.0.38

[GHD]

Continuing the search for differences in lat/long bedtween ADE and the GP editor, I decided on a systematic approach.

Starting with a taxiway network in which I can add nodes and straghten links, I created a series of boxes:



I then locked every node on the taxiway network so that they couldn't move. Then, created polylines and carefully copied/pasted the taxiway nodes to the polylines:





However, if I try to edit the polylines I get an error (see later post)

 

[GHD]

Don,

Could you please recheck the "Reset" button operation?

I used it on my 5 sided polygon to attempt to remove the texture mapping but it didn't.

So, starting from scratch, I redrew the polygon and using only 'resize' with a final move of the two point opposite side, I got a reasonable representation:

 

[scruffyduck]

George

Are the taxi lines coincident in ADE with FSX in your first posr above? We need to be sure if the method used by ADE to generate coordinates is giving an error or whether the problem lies with the GP objects.

Also it would be nice to see if the same problem is present in FS9. If it is not then we can be pretty sure that the issue is in the corrections needed to handle the round earth model in FSX.

 

[GHD]

Are the taxi lines coincident in ADE with FSX in your first posr above? We need to be sure if the method used by ADE to generate coordinates is giving an error or whether the problem lies with the GP objects.

I would say they are pretty much spot-on:

Also it would be nice to see if the same problem is present in FS9. If it is not then we can be pretty sure that the issue is in the corrections needed to handle the round earth model in FSX.

I would rather not test in FS9 since it adds data files to all scenery areas which messes up my defragmentation. Perhaps Tom might like to try it.

 

[scruffyduck]

OK- thanks George. Hopefully Tom can carry out a test

 

[robystar]

fs9 on 0037

Same happens in FS9 (90º true, 3500 ft taxiway, shift =12 ft to the east)

 

[scruffyduck]

Thanks Roby

So on that basis it seems to be something in the way that the GP Library handles coordinates or the way ADE sends them to the library

 

[gadgets]

So on that basis it seems to be something in the way that the GP Library handles coordinates or the way ADE sends them to the library

I hope to have a "handle" on that later today. My suspicions are that ADE is using a flat-earth model to calculate lat/lon from X/Y offset from ARP but that the GP Editor handles those quantities with round earth computation.

A way to find out before I get around to it would be to create two identical objects, one close to the ARP, the other some distance away (>1nm) and check vertex offsets when the user A/C is positioned over vertices on the ADE display.

Should that prove to be the case, Jon, there a couple possible solutions which don't involve changes in ADE.
Don

 

[GHD]

I think my upload is faulty,

After setting all of the vertices to the lat/long of the taxiways, I cannot edit the GP polys.



Send home message sent.

Can Jon please look at the attached project and see whether it is recoverable? If not, I have an awful lot of work to repeat

 

[gadgets]

George, that is an internal GP editor issue and will not have affected ADE (unless an issue in ADE caused it, of course)

Don

 

[GHD]

Thanks Don.

I deleted all of the polylines and recreated them. I then set the vertices to the same as the taxiway nodes. As soon as I try to edit, I get that error.

There is nothing wrong with the uploaded ADE file.

 

[scruffyduck]

So you don't need me to check the file George?

 

[GHD]

So you don't need me to check the file George?

No, as far as I can tell, the ADE file is OK.

I can compile it but the polylines are as they were initially created. I cannot edit the polylines after their vertices have been moved.

 

[tgibson]

Note that I am getting this same error, in my GP Texture Editor thread. I assume you have not touched the GP Texture Editor? If not, then it appears it may be related to the GP Editor and not the GP Texture Editor as I suspected?

 

[GHD]

No, I added my texture directly through the txt file.

 

[gadgets]

Version 0.0.09, just posted, fixes the exception. It was due to something I broke yesterday when making changes to accommodate horizontally-oriented line patterns. (I copied a line of code that didn't work properly in its new location.)

Don

 

[gadgets]

After running only a few tests, it definitely appears that there is an issue between how ADE calculates lat/lon and how ADE_GP uses thouse quantities. But, I'm not sure it's due to flat-earth vs round-earth.

When an object is located close to the ARP and the aircraft is located directly over a corner of the object in FSX, there is little or no offset between the corresponding vertex and the aircraft on the ADE display. When an object is located distant from the ARP and the aircraft is located directly over a corner of the object in FSX, there is a significant difference between the aircraft and the vertex on the ADE display.

In the test case, the distant object was about 600m from the ARP, and the difference was about 1.3 m. That's far more that I would expect from round-earth/flat-earth. What make it even more curious is that the offset is only in the X-plane, i.e., longitude (as George's ellipse example yesterday demonstrates). In the Y-plane, there was no discernable offset.

Now that I know what I'm looking for, my next step is to check the longitude conversions in ADE-GP and run a few tests.

More later.

Don