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Eduard: Swiss-Style Relief Shading for Maps Using Machine Learning

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Re: Eduard: Swiss-Style Relief Shading for Maps Using Machine Learning

#61

Post by mistrial9 »

stdbrouw wrote: post #52

My first impression was also "huh, why would you need a neural net for that?" but I suppose it's a little like brute force calculations in science in cases where probably with some effort you could find an analytic solution -- at a certain point just throwing computation at the problem beats finessing a tidy understandable algorithm to account for e.g. for the small differences in the direction of the shading that se…

hmm this is important and deserves more clarity. Algorithmic computer science is used and taught widely, in a hundred programming languages. Machine Learning is a statistics-based group of techniques using data to guess reliably the values in new data. Machine Learning is often called a subset of AI, but there is no real definition of AI except "doing something with a computer that previously required a human"

So the change here is .. instead of pre-written rules to determine outcomes.. use a lot of data, read and build a model from that data, to predict with statistics what the new result should look like given similar inputs.

Machine Learning is data-driven to predict, while algorithms use math and loops to derive answers.

Re: Eduard: Swiss-Style Relief Shading for Maps Using Machine Learning

#62

Post by detourdog »

shrx wrote: post #25

I don't get it why ML is needed. Just download a DEM (for example, an aerial LIDAR map or SRTM), import it in QGIS along with your base map raster, choose the appropriate shading parameters and combine the two with appropriate blending. edit: and if you're feeling fancy, you can render the relief shading in blender: https://somethingaboutmaps.wordpress.com/2017/11/16/creating...

I don't think it is that ML is needed. I think the point is to use a very sophisticated/nuanced rendering system for topographical maps. Could be Blender is too big of dependency for what they have planned. This seemed like an above average use for ML of an HN submission to me.

Re: Eduard: Swiss-Style Relief Shading for Maps Using Machine Learning

#63

Post by detourdog »

folli wrote: post #55
martopix wrote: post #47

Earlier quoted context omitted.

> the light comes from North West, which is impossible in the northern hemisphere that is technically not correct, in the summer for sufficiently high latitudes, the sun sets in the northwest.

I agree, I misworded the statement, the sun does indeed shine from northwest for a couple of hours in the summer months in Switzerland as well. The point in the linked article is that the grandseigneurs of Swiss topography didn't like that the usually sunny and warm south slopes show up dark and shaded in the map (and the other way around). They felt this to be unnatural and an error to be corrected. That was back in…

Could it be that it renders the sunlight at the appropriate time of year to be on that face of the mountain? I always want to be on the sunny side of the mountain in summer...

Re: Eduard: Swiss-Style Relief Shading for Maps Using Machine Learning

#64

Post by billfruit »

folli wrote: post #56
steve1977 wrote: post #45

Earlier quoted context omitted.

As a Swiss guy, I had no idea this was a thing. But then again, I'm also not surprised we needed to have our own special way of doing it.

I think it's a very interesting bit of Swiss history. All the work of Dufour (the General of the Swiss Confederation Forces in the Sonderbundskrieg) and his team in measuring, mapping and producing one of the highest quality topographical maps that still holds up today.

But Dufour maps use "hachure" [0] lines for relief, not this type of shading, I think.

[0] https://en.wikipedia.org/wiki/Hachure_map?wprov=sfla1

Re: Eduard: Swiss-Style Relief Shading for Maps Using Machine Learning

#65

Post by c3534l »

steve1977 wrote: post #45
folli wrote: post #14

In Swiss-Style Relief shading, the light comes from North West, which is impossible in the northern hemisphere. This makes sunny south facing slopes shaded and shaded north facing slopes light. Legend says that this was an intentional design decision, because right handed people usually have their desk lighting on the top left of their desk, giving the map a 3D like appearance. Here's an article on the topic (german…

As a Swiss guy, I had no idea this was a thing. But then again, I'm also not surprised we needed to have our own special way of doing it.

It seems natural that people living in the mountains would have a robust topographical tradition.

Re: Eduard: Swiss-Style Relief Shading for Maps Using Machine Learning

#66

Post by brendan8229 »

Very interesting. We've worked on implementing a UI to choose settings for hill shade tiles and then use gdal on the fly using the MapZen Terrain tiles (https://www.clockworkmicro.com/terrain-tile-styler). But of course in this case the settings are still applied globally. It certainly makes sense to change the light source and azimuth regionally.

Re: Eduard: Swiss-Style Relief Shading for Maps Using Machine Learning

#67

Post by mthoms »

sorenjan wrote: post #60
folli wrote: post #20

Earlier quoted context omitted.

Thanks for trying it out! I like the idea about the dynamic center of rotation, I have not thought about this. Let me know if you have any other suggestions: contact@cubetrek.com

One of my pet peeves is when I zoom in to a 3D model and the rotation is somewhere far off screen, most of the time the model center. It makes it very difficult to orient yourself when rotation also moves what I was looking at off screen. I think Google Earth (desktop) does it well, it rotates around the point where the mouse cursor is pushed. So you push the center button, it shows a marker where the pointer was, an…

I think Google Earth has two options - you can keep the "camera" fixed and change the direction it's looking, or - you can rotate around a point on earth. I can't remember the details but this is accomplished using different modifier keys + the arrow keys.

Re: Eduard: Swiss-Style Relief Shading for Maps Using Machine Learning

#68

Post by nestorD »

mdp2021 wrote: post #26
nestorD wrote: post #11

Earlier quoted context omitted.

It does look like it would be doable without neural networks. My guess (having read their paper but not worked in the domain) is that it would be doable but requires a lot of iterations, tweaking parameters and dealing with corner cases. That would give you something running almost instantaneously but it would take a year to develop with tight feedback from domain experts. Or, you can throw a (relatively standard for…

The chances of the problem not having being already tackled with deterministic algorithms is the thinnest - and in fact, yes, there do exist tools, as expected. See the sections about 'hillshade' at the OpenTopoMap "from scratch" instructions, at https://github.com/der-stefan/OpenTopoMap/blob/master/mapnik...

It has but I am hoping that a paper accomplishing the task with machine learning will move the goalpost (it has happened in other areas of computer vision).

Re: Eduard: Swiss-Style Relief Shading for Maps Using Machine Learning

#69

Post by mdp2021 »

nestorD wrote: post #68
mdp2021 wrote: post #26

Earlier quoted context omitted.

The chances of the problem not having being already tackled with deterministic algorithms is the thinnest - and in fact, yes, there do exist tools, as expected. See the sections about 'hillshade' at the OpenTopoMap "from scratch" instructions, at https://github.com/der-stefan/OpenTopoMap/blob/master/mapnik...

It has but I am hoping that a paper accomplishing the task with machine learning will move the goalpost (it has happened in other areas of computer vision).

> move the goalpost

I don't think I understand your expression there: do you mean that "the problem of producing relief bitmaps from elevation data could lead to new achievements in our knowledge relevant to Neural Nets"? I am not sure why.

If you mean, more consistently with your original parent post, "lead to improvements in the past traditional techniques towards the same goal" - I would say that I don't see much space for leaping better results than those already possible.

Re: Eduard: Swiss-Style Relief Shading for Maps Using Machine Learning

#70

Post by momirlan »

folli wrote: post #14

In Swiss-Style Relief shading, the light comes from North West, which is impossible in the northern hemisphere. This makes sunny south facing slopes shaded and shaded north facing slopes light. Legend says that this was an intentional design decision, because right handed people usually have their desk lighting on the top left of their desk, giving the map a 3D like appearance. Here's an article on the topic (german…

the map is not the territory
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