I have managed to get a 3d model of the track surroundings using Google Earth 3D view. The main purpose is I can use it as a 3D template for the actual low-poly modelling – measuring dimensions of buildings and distances between objects should be much easier and more accurate now.
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Even there are some DirectX / WebGL rippers available, they cannot handle the latest versions of Google Earth so I had to use the photogrammetry method.
It is really simple – you just take screenshots of a 3D scene from various angles & distances so you cover all the area you want to “rip” and then load those images to a photogrammetry software (I find Agisoft Photoscan the best) which detects common points in the images, calculates distances between them and these data are used to reconstruct the 3D scene.
Just don’t ask me about that black magic algorithms behind that… thank you 🙂
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Of course the model you get cannot be used directly in the game because it is too high-poly and if you try to decimate it you will still get really bad mesh layout which would be pain to work with. The second reason is that the reconstructed scene uses one extra-large texture and as you know you must be as efficient as possible to get good performance of the game. One of the basic method is to create all those 3D assets the way that they can be textured with a repetitive images and models you get from those photogrammetry tools simply does not allow that.
But I think I will be able to use low-quality photogrammetry scene for the far scenery though.
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