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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

#51

Post by mdp2021 »

pixelesque wrote: post #37
mdp2021 wrote: post #32

Earlier quoted context omitted.

> depends In fact it works with the provided example but, empirically, it does not on area detail of detailed maps. Crests and valleys will switch. > computer UI buttons That is a consequence of consolidated established style, not a cause. > the whole of Africa It will work on the view of the full shape but it will not on the area detail, where the viewer will lose the notion of global position and attempt to interpr…

> In fact it works with the provided example but, empirically, it does not on area detail of detailed maps. Crests and valleys will switch. I don't think that's always the case though: I think it's likely similar to optical illusions: you can technically correctly see it both ways, but it depends on the person's brain and what they're used to as to how their brain sees it. > That is a consequence of consolidated esta…

> always the case

Try it. In my initial experiments as a cartographer, as is normal for learners I did "fix it", and tried "boreal morning or afternoon real light directions": the effect will be wrong, in an actual map. ...Learners "make it the right way" and learn that the """right""" way is wrong.

> more readily

Sure consolidated UIs will contribute in the spiral of circular consolidation of natural ("brain") patterns and conventions, but the "light from top-left" use predates UIs by very many centuries: when we read a document it is more typical to have it lit, not darkened by one's own shadow from a body interposed between sun and document; when we gather around a fire we face it.

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

#52

Post by stdbrouw »

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 seem to define good manual shading.

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

#53

Post by _nalply »

mytailorisrich wrote: post #49
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.

Yes, not sure in Switzerland but that's indeed the case in the UK.

It happens in Switzerland, too, at least perhaps west-northwest. We have a north-facing window (at latitude of almost 47° North) and in summer the room gets sun both early morning after sunrise and late evening before sunset.

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

#54

Post by avidphantasm »

As a primarily macOS user who works with geospatial data, and laments the lack of native GIS tools on macOS, it’s nice to see this in the app store. However, it seems like releasing this as a QGIS plugin would make more sense (though it would be harder to monetize I guess).

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

#55

Post by folli »

martopix wrote: post #47
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 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 the 1920s and obviously has not been changed.

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

#56

Post by folli »

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.

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.

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

#57

Post by eloisant »

mdp2021 wrote: post #23
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…

But if you try using the factually correct angle (light from some angle in the south), the result is misleading to the eye.

Why is that misleading?

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

#58

Post by orbital-decay »

flohofwoe wrote: post #36
TJSomething wrote: post #33

Earlier quoted context omitted.

The biggest thing that I'm seeing that Singh has over Huffman is the adjustable detail-preserving terrain smoothing. Detail-preserving blur algorithms don't generalize well. Application-specific NN solutions tend to excel at this problem, by having a model of what details are important vs incidental. I would like to see a combination of the two, with the terrain pre-processed before being used in Blender.

This is a similar problem as automatic LOD computation for 3D game assets though, and that has been done for a long time without ML (but maybe ML may actually help there too, no idea). I still find the 'human touch' argument a bit unconvincing for this type of problem.

ML is absolutely being used in automatic LoD computation for far better results, as well as in other geometry transformations (with Unreal Engine introducing the generic "ML Deformer", for example).

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

#59

Post by contravariant »

eloisant wrote: post #57
mdp2021 wrote: post #23

Earlier quoted context omitted.

But if you try using the factually correct angle (light from some angle in the south), the result is misleading to the eye.

Why is that misleading?

Probably because the predominant direction of light is the south. That would mean lighting it from below, which looks unnatural because we're used to stuff being lit from above.

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

#60

Post by sorenjan »

folli wrote: post #20
antipotoad wrote: post #19

Earlier quoted context omitted.

Looks really nice. One comment from a usability perspective: it would be nice if the center of rotation were a point on the trail, rather than a point somewhere underneath the landscape. Better still if that center point was dynamic as you pan around the map, such that it’s always the ‘middle’ point of the trail segment that’s in the viewport (at least, I think that’s what my brain is telling me it wants, I might be…

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, and then you rotate by moving the mouse.

At the very least I think the rotation center should be on the surface and on screen.

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