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Comment by LeonM | Hacker News Reader

I'm really impressed by the amount of detail in the 3D views (hold middle mouse button to look around).

Even the fair at the field near my house [0] can be viewed in 3D!. Coincidentally they are currently building that same fair today, so for a moment I thought the images were live...

[0] https://earth.google.com/web/@52.08511654,4.31805086,0.37952...

View on HN

Same place on google maps, that works on every browser that supports WebGL: https://www.google.pt/maps/@52.0849891,4.3169948,78a,35y,77....

How are they building the 3D views? Mapping cars driving around with sensors? I was under the impression that the shapes were inferred from satellite images, but the moment I step outside the major cities, it's back to flat maps. Even the couple hand-modelled buildings previously present in maps seem to be missing here.

This is exactly what I want to know. There's several towns in the UK that have all the houses in really good 3D (mostly the coastal towns) - I struggle to believe that there's a team of humans making these...

There's a (yuuuge) public Lidar dataset for the UK:

https://environmentagency.blog.gov.uk/2015/09/18/laser-surve...

One of the motivations for the collection was flood analysis, which overlaps with your observation about coastal towns.

I'm not sure that's it's only LIDAR data. There are e.g. some cranes and scaffolding that also are 3D modeled. I assume it's some magical machine learning pipeline that accumulates the aerial and street view imagery, LIDAR where available, and generates a 3D model.

It's done by plane, though I'm not sure what sensors. More than just photography.

It is possible to use satellite imagery for photogrammetry [1], but Google is using imagery from airplanes, possibly combining it with ground level data from their street view cars.

[1] http://www.vricon.com/

SLAM techniques allow reconstruction of a scene from video+position data. As the aircraft takes video of the terrain, it is logging its position. Large-scale batch processing can recover the 3D positions for each image feature that will minimize some error metric.

Rural areas probably have lower-quality image data (or noisier aircraft position data).

Google Earth’s Incredible 3D Imagery, Explained https://www.youtube.com/watch?v=suo_aUTUpps

Maybe I'm just in an area where buildings are a tad more complicated than simple boxes, but around here the results vary between acceptable and catastrophic. As if buildings were haphazardly thrown together in all kinds of weird angles and shapes. I know there are limits to what technology can do, but overall I liked the combination of flat texturing and hand-modelled buildings better.

They also seem to have lots of trouble with pieces floating in the air, which imho could just be pruned (e.g. lots of floating train tracks here, presumably where there also has been a train at the point of geometry capture: https://earth.google.com/web/@48.51659545,9.06299404,316.491...)

The detail is great but the coverage seems limited. There's no 3D in Moscow, Kiev, Beijing or Singapore as far as I can tell, for example.

How can you look around on a Mac trackpad?

Hold shift/ctrl then click+drag.

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