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[Unca-Fester]

Woah  your using X-Plane's Apt dat!

So can users of this editor also add their own custom fields?

[Stainless]

Yes, the apt.dat file gives me 34000 airports we can work with without major work, so it was a no brainer really.

What sort of custom fields would you like?

[Stainless]

Well a bloody frustrating day.

I found a site which said it had complete Lidar data for the British Isles. So of course I grabbed a load of it. What could be better for the terrain. 

So I wrote a parser and converted the data into several useful formats.... which is where things went horribly wrong.

First I noticed that because it's Lidar, it picks up buildings.



NOT GOOD..... NOT GOOD....

Then I noticed the data was not complete at all. Large areas have not been scanned......




So I went away and had a cig. While on the balcony, looking at the snow falling, I had a brain wave. Maybe the objects in the airport editor were in geocentric coordinates instead of geodetic.

So I wrote some code to convert between the coordinate systems, and yes they were different.... but now my objects are a few kilometres out of position instead of a few metres......

Not a good day.

Stainless needs beer badly.

[sniperton]

Now imagine that you're pleanning a precision bombing strike based on coordinates...
A beer won't suffice, you'll need a whiskey in addition. 

[Stainless]

Still frustrated.

I now parse the terrain files from flightgear and display the terrain around the airport.

This has shown up some more problems.




The white areas are patches of untextured terrain. You can see they don't join up... which they should.

You can also see a second copy of the airport, this is a BTG (terrain object).

It has a different alignment than the one generated from the apt.dat and is a different size...... WTF is going on.

[Stainless]

Well I got fed up with trying to figure out what the hell was going on.

So I just did a major rewrite of the code to use ECEF coordinates. So far I have done the terrain and the objects as the data for them is already in ECEF coordinates.

Already looking sensible.




The terrain is white because the texture is set to "SomeSort" .... which seems to be a generic material.

The objects look to be sensibly aligned, and positioned. The runway in the back is a BTG file not the one I generated from the apt.dat file.

That is my next task

[Pursuivant]

So I wrote a parser and converted the data into several useful formats.... which is where things went horribly wrong.

Silver lining:

That LIDAR data with all the buildings could somehow be edited to allow (partial) photoreal autopopulation - at least for the UK ca. 2018.

As a temporary overlay, it can also be used to double check placement of roads, railways, etc.

Obviously, jobs for another time or even another person, but my initial reaction when I saw all those ghostly buildings was, "that looks incredible!"

I've always thought that for historical flight sims, rather than attempting to use modern STRM data, the better thing to do might be to scan in old photo recon photos or ordinance survey maps, use AI to train the computer to recognize various terrain features (and, maybe even estimate altitudes in the case of stereoscopic photos), and build a map based on that data. The map based on historical data could then be cross-checked against modern STRM data for general accuracy.

[Stainless]

There is a program on the history channel that has used stereographic photography from WWII to create 3D recreations, so I guess it would be possible.

IF you could get access to the stereographic data. 

[Unca-Fester]

Yes, the apt.dat file gives me 34000 airports we can work with without major work, so it was a no brainer really.

What sort of custom fields would you like?

Well in FG you have to be adept at using the terrain editor TerraGear to add in anachronistic airfields like old WWI ones for France, even though several if not a dozen or more of the modern fields were once WWI, their size was smaller and outlines different.  I added Stow Maries to the UK, ( just the buildings, the 'field' it's located on is a crop_grass landclass mesh and works for a WWI era field.) even though it's not given a location in apt.dat, it would be nice to add custom airfields without resorting to a tedious external program.

[Pursuivant]

There is a program on the history channel that has used stereographic photography from WWII to create 3D recreations, so I guess it would be possible.

Most photo recce pictures from WW2 were taken using stereographic cameras, specifically so that intelligence analysts could see the combined images in 3d using stereographic imagers. Basically, fancier versions of the Victorian/early 20th century "stereoscopes."

If you had the images properly set up, you could view them through a pair of digital cameras and possibly have a computer automatically set up 3d images based on interpolating the two different images. Obviously, not a project for this flight sim but the technology seems fairly straightforward.

Even better, in addition to all the archived USAAF and RAF photo recon images from WW2, the US and UK also snaffled up all the Luftwaffe PR images after the war (Operation Dick Tracy). All those millions of lovely photos are currently sitting in national archives near Washington and London, just waiting for someone to make a detailed 3d maps of Europe, North Africa, etc. ca. 1942.

[Stainless]

This week I started a tool to convert IL2 meshes to game meshes.

Designed to be easy to use.



There are only two settings, source directory where all you IL2 mods are, and the destination directory you want to store the converted objects.



Just hit load and navigate to the him file





Then load it.



You can rotate the object with the left mouse button, and rotate the light source with the right mouse button. The mouse wheel zooms in and out.



Then just hit save.

The result is a directory containing a large text file which is the game object. This can be loaded into the game object editor and tweaked.

[DarkBlueBoy]

Bloody Hell Stainless! That is brilliant.