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A new kind of map: it’s about time

blog.mapbox.com

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Re: A new kind of map: it’s about time

#31

Post by sulam »

Isochronic maps are pretty awesome. However, an isochrone-only projection that ignores geography is prone to the same sort of errors that the alternative creates. One simple example that is personal to me -- when I moved from SF to the East Bay, my commute into the city shortened by ~10 minutes because of where I'd been living (out by Ocean Beach) vs where I moved to and the nature of driving and public transit in the SF Bay Area. And yet as far as my friends who lived and worked in SF were concerned, I was now in this mystical place that they didn't really spend any time in or know much about (the perception of Oakland is also contributing here).

It'd be interesting to take travel data and cluster it such that you end up with an isopsychochronic projection. Commute visualizations I've seen end up feeling kind of close.

http://news.nationalgeographic.com/2016/11/us-commutes-revea...

Re: A new kind of map: it’s about time

#33

Post by microcolonel »

qznc wrote: post #11
microcolonel wrote: post #8

Earlier quoted context omitted.

For what it's worth, I think it would be computationally quite hard. You would have to pick a set of points and maybe isomap them from three dimensions (x, y, and time) to two, then find a visually acceptable cage transformation using those points as anchors. You'd have to do this for each query.

The Isochrones [0] mentioned in the article include basically all the necessary information. I guess a capable GPU-shader programmer could easily render the distortion in real time. (Hint Hint Hacker News for a cool weekend project) [0] https://www.mapbox.com/bites/00156/#10/51.6840/-0.1480

That looks pretty good! It seems like the transformation could be done reasonably quickly, maybe with a two-component texture (not sure how efficient texture sampling in vertex shaders is), in the vertex shader(s) in that Mapbox GL instance right after the basic projection. I might give this a go. It might get a bit weird around the edges though, gotta make sure to have a margin of additional geometry.

Re: A new kind of map: it’s about time

#35

Post by nkoren »

microcolonel wrote: post #8
qznc wrote: post #6

Earlier quoted context omitted.

This. I was hoping for some weird pictures of distorted maps.

For what it's worth, I think it would be computationally quite hard. You would have to pick a set of points and maybe isomap them from three dimensions (x, y, and time) to two, then find a visually acceptable cage transformation using those points as anchors. You'd have to do this for each query.

I suspect it would be relatively straightforward. Treat each datapoint as origin of a voronoi cell, in both realspace and travel-timespace. This would give you appropriate cage boundaries on both maps, and the transformation between them should be easy.

Re: A new kind of map: it’s about time

#36

Post by danso »

Pretty neat. I frequently use the example of Yelp's list and map views as an example of how maps aren't always better, even as they are more appealing compared to a text list. But I frequently use the list view because I can sort by distance, while still seeing the other important info (such as star rating, cost, food type).

But distance isn't the only important geospatial factor. Frequently I want to find a place to eat/drink that's on the way to another destination (such as a movie theater). This kind of chrono map would be more useful in a new city in which I don't know that a place 0.2 mi away to the west involves crossing an interstate. In a setting I'm familiar with, it's probably not particularly useful on mobile (given the limited dimensions for showing points and text labels), but could be great on print displays. It'd allow designers to show geospatial/time info without also having to render a full map.

On the topic of Yelp and other listing services, maybe some refinements could be made to make lists more geospatially useful. No reason why the list view has to show just distance, rather than time traveled. Or to include a filter option for direction, so that I can just see things west or south of me. It's pretty frustrating sometimes having to switch back and forth between list and map.

Re: A new kind of map: it’s about time

#37

Post by danso »

wavefunction wrote: post #20

Removing the geography seems great until you are trying to cross rivers or highways.

Ostensibly, these kind of maps imply the time-cost of those obstacles more accurately than a standard map in which as-the-bird-flies distances are more explicitly shown.

Re: A new kind of map: it’s about time

#38

Post by peteretep »

peatmoss wrote: post #23
hnnsj wrote: post #19

How is this more useful than an ordered list of search results, exactly? Once you've picked your destination, based on travel time, you still want figure out how to get there.

If you were interested in trip chaining, you could still pick the direction you wanted to head.

The map doesn't guarantee that at all. Two items on the map can appear next to each other and take a very long time to get between -- perhaps they're separated by a freeway that you can't cross, for example.
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