Tokyo released point cloud data of the entire city for free | Hacker News Reader

Tokyo released point cloud data of the entire city for free

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314 pointstaubek40 comments

Link: https://info.tokyo-digitaltwin.metro.tokyo.lg.jp/3dmodel/

What do I need to click to get the pointcloud version? I'm just getting regular untextured polygons.

The table "Posted data on 3D Viewer" contains a row "Point cloud data" with several links, e.g. "Viewing the LP point cloud of the Tokyo Metropolitan Government area in the viewer": https://3dview.tokyo-digitaltwin.metro.tokyo.lg.jp/#share=s-...

Supposed to be [1][2] according to [0] but only by lots of clicking through GUI? It's really intuitive. GSI(Geospatial Information Authority of Japan) download site is a lot better, though they're more geography focused.

0: https://twitter.com/tocho_digital/status/1697474739583746474

1: https://catalog.data.metro.tokyo.lg.jp/dataset/t000029d00000...

2: https://catalog.data.metro.tokyo.lg.jp/dataset/t000029d00000...

3: https://fgd.gsi.go.jp/download/menu.php

Free reminder that the USGS is involved in an epic, nearly decade-long collection of mid- and high- density lidar of the entire continental USA, and the QC'd data (point cloud & derived) is published gratis for everyone to use:

https://www.usgs.gov/3d-elevation-program

https://www.usgs.gov/media/images/3d-elevation-program-fy25-...

https://www.usgs.gov/3d-elevation-program/3dep-spatial-metad...

I must say this is tremendous. There are many different AIGC explorations in 3D topics, with such high quality dataset, it will greatly assist current workflow and accelerate the 3D creative evolution.

A couple of cities have been doing this as well. Vancouver Canada has lidar point clouds covering the entire city, going back to 2013.

[0] https://opendata.vancouver.ca/explore/dataset/lidar-2022/inf...

[1] https://x.com/edwardjxli/status/1871676981143875725

https://www.swisstopo.admin.ch/en/switzerland-in-3d

> Switzerland is one of the first countries to possess a detailed 3D buildings model covering the whole country. This digital model of Switzerland consists of approx. 70 million 3D objects. Besides every single building in Switzerland and the Principality of Liechtenstein, bridges, cable cars, forests, individual trees and geographical names are also represented in 3D. Two movement modes enable interactive navigation through space. Discover digital Switzerland from the air in flight mode or take a virtual stroll around a 3D model of your own village or neighbourhood.

Crashed on my old iPhone 6SE, but could tell it was getting cool!

This might be a stupid question, but isn't Switzerland known for its countless hidden bunkers and defense positions? Doesn't mapping and publicly exposing basically the whole country only bring negatives and nothing positive?

One would reasonably assume threats could map surface-level objects from orbit. The Swiss (I hope) would consider this and react accordingly.

I have one of such fortifications, called Toblerone line, running around our place in canton Vaud. The whole line is maybe 15km long from Geneva lake up the Jura mountains, made up from concrete spikes (even raisable in the middle of roads), blowable bridges and around 15 tiny concrete fortresses (fortinettes), all in plain sight, mostly visible on google maps/street view.

All built around 1930s. There is popular hiking trail along all this, since nature and forests around it are pretty and well maintained. No secret really. Same for many other old stuff. New stuff should be hidden on bases/remote places.

Btw checked our building and surrounding ones and its pretty precise but not up to date with 2024 finished construction.

I though Switzerland's defense was more based around being mountainous and having explosives planted in critical tunnels/bridges and having a large percentage of the population armed and trained for national self defense. Basically in a ground invasion would be deadly and slow with no mobility and resistance everywhere.

Besides that it's hard to imagine which foreign power would have incentive and power projection to even try it.

The way I've understood it is that none of their defense is hidden, it uses the natural and societal benefits. Most of that could be gleaned by anyone with access to satellite images and wikipedia.

That might all be outdated info though, it'd be interesting to see where I'm wrong though!

There are laws in Switzerland stating that essentially every cirizen has to have a bunker close by. Thus many homes got a bunker.

https://www.swissinfo.ch/eng/culture/bunkers-for-all/995134

Historically that has been the case for for Sweden as well I think. Every older apartment building I've lived in (built before 1990-ish) has had bunkers in the basement, and usually it seems to be sized for more than just the buildings residents (although it is repurposed for storage these days). Thick steel doors and all the other tell-tales of old civilian bunkers.

I'm guessing other European countries did this too.

I visited a friend in Zurich recently who has such a bunker in their house. ( now a wine cellar)

Surely this was before nukes? After reading “nuclear war: a scenario”, I’m really not sure there’s much use surviving the initial blast anyway.

Non-nuclear invasions are still happening around the world.

I've definitely seen clips of heavy artillery tucked away into friendly barns and garden sheds. Maybe there's just wealthy people who like to collect large guns and there's some pride in turning away a Nazi invasion with their defenses.

Here's a cute video I found discussing the line of 12 fortresses protecting a little bottleneck of a river valley - he explains that the two camouflaged as villas are done so as not to be eyesores for the tourists.

https://youtu.be/tPL9-L2gwzo

https://www.slate.com/blogs/atlas_obscura/2015/06/12/the_vil...

EDIT a few more examples here

  A former infantry bunker is camouflaged as a medieval house in the town of Duggingen. Notice the half-circle windows, which appear to have been painted on

  Nearby mountains have been made so porous that whole divisions can fit inside them. There are weapons and soldiers under barns. There are cannons inside pretty houses. 

  If you look closely, you can see a massive door in the hillside that would swing open - A Swiss Air Force Mirage III RS outside its mountain hanger.

https://mathewingram.com/work/2022/02/14/switzerlands-hidden...

Map says it's a building, not what's in the building or how sturdy the building is. The thing that looks like a barn might not be a barn.

I wonder if this dataset has been added to OpenStreetMap (or what the legal restrictions could be). If I look at Zurich on https://osmbuildings.org/ it seems like it has all the buildings in 3d.

In france, the national geodata institute (IGN) has captured lidar data of the whole country (20 points per km2 if memory serves, in the OP it’s 30p per km2).

https://diffusion-lidarhd.ign.fr/visionneuse/?copc=https:%2F...

Background on the Tokyo government’s digital twin program, including sourcing and maintenance efforts

https://github.com/tokyo-digitaltwin/roadmap_v1.0/blob/main/...

xcancel.com with proxy enabled in its setting for media seems to work

So fun to explore, it has to be the greatest city on earth, just a marvel in so many ways.

I would love to use point cloud data like this to make a map for a video game. What is the state of the art for turning point cloud data into 3D models?

Anyone know what the best of the best is?

What would the game be like? There are many ways to get as-built buildings at scale from existing datasets. For example there are cesium tiles. OSM data contains footprint polygons with height which means extrusion is trivial.

To explore know production algorithms for pointcloud-to-mesh check out the ones provided in cloudcompare and meshlab and see if any fit your purpose. Afaik there is no one objectively best recipe so you need to know what you want and be aware of the tradeoffs and constraints.

Note that for real time large scale cityscapes for complex buildings you likely need lods, impostors etc - which you don’t get for free. If you use just polygon extrusions you can likely bucket like a square kilometer of buildings to a drawcall (or more).

Simplygon is used in MS Flight Simulator bcs it can generate seamless LODs. LOD 0 can simply be a Delaunay triangulation.

some parts of germany are also available. some buildings are simple, some have a really good 3d model. for example here is the data for bavaria https://geodaten.bayern.de/opengeodata/OpenDataDetail.html?p...

How do they collect point cloud data at scale?

speculating: Lidar from a plane?

https://www.reddit.com/r/Albany/comments/1hdxkz0/comment/m1z...

Imagine a route like this, except many lanes. I was trying to find a pic I saw the other day of one over NYC

slightly better:

https://www.reddit.com/r/flightradar24/comments/u59zc2/off_t...

https://www.yellowscan.com/knowledge/drone-flight-planners-t...

I do this sort of stuff for work. Plane borne lidar is typically only part of the answer, and usually a hybrid acquisition model is required.

Are there drones that can provide similar products at parity (versus needing aircraft)?

Here's a link to the people out of Huntsville, AL who do a lot of survey acquisition work in America, and did the collection effort noted in the Reddit post below. [1]

The About Us video shows some of the planes, equipment, collection flights, survey patterns, and data applications for the collection efforts. Other pages have notes on the planes and work done.

[1] Revolution Flight, Survey Subunit, https://www.surveyaircraft.com/about-us

Great for cgi and video games

Feels like where Google Earth was 22 years ago

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