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3D map of the Czech Republic, made from 12.5cm/px imagery (2017)

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Re: 3D map of the Czech Republic, made from 12.5cm/px imagery (2017)

#31

Post by dividuum »

zokier wrote: post #19

Anyone with MSFS, how does its terrain compare? Both are based on conceptually similar tech?

The raw terrain texture and height data is probably a bit lower res in most cases. Some places have photogrammetry, in which case it looks pretty good and looks similar. Outside those areas, which is limited to mostly major cities, any structure you see is auto-generated using some AI algorithm. It looks at the satellite images, open street map metadata and more and guesses what kind of structure matches best. Cities generated that way look ok, unless you fly too close :)

Re: 3D map of the Czech Republic, made from 12.5cm/px imagery (2017)

#33

Post by yojo »

sorenjan wrote: post #13
dvh wrote: post #9

And the practical application of data like these: https://prehrada.hrach.eu/en.html

This looks very useful and would bring electricity prices way down. The best time to start building would have been years ago, the second best is today!

I assume you’re joking, but in case you’re not - the plan would put the capital city (Prague/Praha) under 200m of water.

Re: 3D map of the Czech Republic, made from 12.5cm/px imagery (2017)

#34

Post by reaperducer »

folli wrote: post #26

Very nice! Obligatory and shameless self promotion everytime the topic of 3D maps comes up: I recently created a web app to visualize GPS tracking files in a 3D terrain. You can upload your GPX or FIT files and it generates the 3D Terrain using Babylon.js It's called https://cubetrek.com

I recently created a web app to visualize GPS tracking files

Off topic, but since you work with GPS tracking files, perhaps you can recommend a GPS tracking device for me.

Until last year, I used one I got around 2005 that was about half the size of a pack of cigarettes. You turned it on, and it would start logging waypoints at 10 minute intervals to a standard text tracking file on a microSD card. I could unload that text file into my computer and plot the route on a map in a bunch of mapping applications.

It was great because when I was going on an adventure off the grid, or traveling overseas or something, I'd clip it to my backpack and then when I got home look at all the fun places I'd been.

I recently tried to find a replacement on Amazon, and nothing is suitable. They are all:

- Built with a big magnet for clamping to the underside a car

- Just a stripped-down Android phone, so large, fragile, and complicated

- Require a subscription

- Require cellular connectivity

- A watch

- A piece of software

I don't want connected. I don't want to subscribe to anything. I don't want it to drain my phone's battery. I don't want to stalk my ex-girlfriend.

I just want something simple that I can turn on and turn off. I know it's possible, because I had one. I just want to find another one.

Re: 3D map of the Czech Republic, made from 12.5cm/px imagery (2017)

#35

Post by 2Gkashmiri »

folli wrote: post #26

Very nice! Obligatory and shameless self promotion everytime the topic of 3D maps comes up: I recently created a web app to visualize GPS tracking files in a 3D terrain. You can upload your GPX or FIT files and it generates the 3D Terrain using Babylon.js It's called https://cubetrek.com

like,mind=blown.

i was on a trek last month and was following a trail from a gpx file. there was no other guide with us so i had to constantly keep the phone on, try to be on the dotted line and more often i would divert to one side and had going up, we diverted a lot, had to face trouble being rimrocked more than once.

one, i felt like a need for voice navigation on OSM for hiking, just a simple "you have diverted from track, move to right 10 meters to be back on track" followed by "you are on track".

then i felt like the app should have 3d elevation data WITH the gpx track so that i can look at the phone, see the contour and look up at the rock and cross reference. This is 100% what i wanted.

1. is this open source ? 2. can this be added to some hiking app or even to osmand? 3. i tried to add a gpx track and got "Track does not contain Timing data.". if the file does not have that data, why not ignore all that and just show the visualization?

Re: 3D map of the Czech Republic, made from 12.5cm/px imagery (2017)

#36

Post by vetinari »

lucgommans wrote: post #12
UltraViolence wrote: post #10

Awesome. Breathtaking. But the imagery isn't from satellite data, is it? Must be from airplanes.

Indeed, something like 25cm or better is typically shot from airplanes. I don't remember what the physical limit is for image quality given a reasonably sized spy satellite (iirc it's around the 20cm mark), but commercially at least, the high quality imagery is all airplanes. Governments often commission such planes to fly ~yearly at something like 10 cm, as well as commissioning height maps[1], but the very good stu…

> but the very good stuff is not released to the public for privacy reasons.

You can buy the data, the agencies responsible for these data make some decent coin. Yes, they are expensive to obtain, but that is paid by taxpayers anyways, so it is kind of double dipping.

The entire area of Czech republic is available at 0,2-0,125 m per pixel for around ~100k EUR. Not unattainable for those who need it, but not hobbyist price either. For the neighboring Slovak republic, the ortophoto at 0,2 m per pixel is available for free.

Re: 3D map of the Czech Republic, made from 12.5cm/px imagery (2017)

#38

Post by baggsie »

reaperducer wrote: post #34
folli wrote: post #26

Very nice! Obligatory and shameless self promotion everytime the topic of 3D maps comes up: I recently created a web app to visualize GPS tracking files in a 3D terrain. You can upload your GPX or FIT files and it generates the 3D Terrain using Babylon.js It's called https://cubetrek.com

I recently created a web app to visualize GPS tracking files Off topic, but since you work with GPS tracking files, perhaps you can recommend a GPS tracking device for me. Until last year, I used one I got around 2005 that was about half the size of a pack of cigarettes. You turned it on, and it would start logging waypoints at 10 minute intervals to a standard text tracking file on a microSD card. I could unload tha…

Garmin Etrex.

Re: 3D map of the Czech Republic, made from 12.5cm/px imagery (2017)

#40

Post by hoseja »

photochemsyn wrote: post #15

Why don't map sites ever publish 3D as topo lines overlaid on a flat 2D map? It's computationally much cheaper, and it's not too hard to learn to read a topo map, as long as the elevations are printed in a reasonably dense manner.

Protip: open the hiking layer.
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