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Hengefinder: Finding when the sun aligns with your street

victoriaritvo.com

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Re: Hengefinder: Finding when the sun aligns with your street

#41

Post by analog31 »

normie3000 wrote: post #13

I lived a long time in a city near the equator with a prominent east-west street. Commuting west to east in the morning and east to west in the evening meant frequent hengings. The roads don't feel particularly safe when you can't see anything. The town planners might have considered this.

Living in the US Midwest, there are lots of towns that are laid out on north-south grids, including portions of mine. As a cyclist, I take note of the days when the sun is coming up over east-west streets, because the car drivers can barely see where they're going. I once saw a multi-car crash on my own street (fortunately at very low speed) that I attributed to this effect.

Re: Hengefinder: Finding when the sun aligns with your street

#42

Post by TeMPOraL »

TeMPOraL wrote: post #25

I need the inverse of that - an app that predicts how badly a given street will be baked by the sun at current or near-future time, will there be any shadow zone from the buildings, how far will the usable extent of it reach (e.g. not much use of shadow if my head or body stick up beyond the shaded volume). Ideally available on a smartphone. Bonus points for being able to route navigation paths to minimize direct sun…

Update: I just vibe coded myself one, gave me an excuse to play with Antigravity (and then cleaned up/improved with Claude Code). Not posting a link yet because it serves 12MB worth of geo JSON up to the client on first page load, and I'm not eager to wake up tomorrow with a bill for upload traffic spike. But it pretty much does its job as well as it could given quality of available data (OSM), so now I'm looking at improving the data itself.

It currently runs A* for routing between two points on map (no address lookups yet), using either local A* or an OSMR endpoint for base path, and then A* for shadow-aware routing, and shows both, + stats (total time exposed, how much it saves in sunlight exposure and loses in time relative to base), plus has a bunch of debugging overlays so I can validate and diagnose pathfinding and data quality. But I tested it live today, and it mostly checks out with reality (big gap: no data on trees).

Re: Hengefinder: Finding when the sun aligns with your street

#43

Post by DANmode »

cholmdomsky wrote: post #31
russdill wrote: post #26

Earlier quoted context omitted.

Really wish mobile browsers were better liars when it comes to "desktop mode"

Seriously. Plus, what is the problem that some websites are 'fixing' by denying me a choice in how the website loads?

That they’ve chosen gaps between components that are larger than your device screen,

and they either functionally can’t,

or simply don’t want to,

adapt their poorly-designed webapp frontend to.

Re: Hengefinder: Finding when the sun aligns with your street

#44

Post by vritvo »

lefra wrote: post #3

It would be nice to be able to access the website on a smartphone (even if the experience is suboptimal), instead of denying access.

Thanks! This is updated now, and you should be able to access the website https://hengefinder.rcdis.co/ on mobile. You can also download the app with more features at https://hengefinder.com/

Re: Hengefinder: Finding when the sun aligns with your street

#46

Post by vritvo »

fuzzfactor wrote: post #6

It would be good to also have the option for alignment with sunrises in addition to sunsets. For instance in Houston the sunrise aligns with Texas Avenue around the June solstice. Consequently, there are no sunset alignments for the downtown skyscrapers.

Hello, thank you! That option already exists: On the website version, it's available in the "Henge Near Me" tab. You can toggle between Sunrise and Sunset.

There are more features on the mobile version, and it also includes Sunrise and Sunset. Just hit the gear icon on the top right, and toggle between Sunrise and Sunset. Hope that helps!

Re: Hengefinder: Finding when the sun aligns with your street

#47

Post by vritvo »

donfuzius wrote: post #22

Nice, and awesome that it works internationally. One little feature request: provide an .ics download, so that I can add a calendar event, add a link to the original calculation to the the calendar entry.

Hi, thank you! The feature to add to your calendar exists!

In the mobile app: long tap on map to drop the pin + alignment arrow. Move the arrow to the line of the road. The "Henge Information" panel slides up from the bottom and has an option to export the henge date to the calendar.

If you're using the website version: it's in the "find a henge" tab. Once the henge is found, you hit "Add to Calendar"

Re: Hengefinder: Finding when the sun aligns with your street

#48

Post by ben_w »

TeMPOraL wrote: post #42
TeMPOraL wrote: post #25

I need the inverse of that - an app that predicts how badly a given street will be baked by the sun at current or near-future time, will there be any shadow zone from the buildings, how far will the usable extent of it reach (e.g. not much use of shadow if my head or body stick up beyond the shaded volume). Ideally available on a smartphone. Bonus points for being able to route navigation paths to minimize direct sun…

Update: I just vibe coded myself one, gave me an excuse to play with Antigravity (and then cleaned up/improved with Claude Code). Not posting a link yet because it serves 12MB worth of geo JSON up to the client on first page load, and I'm not eager to wake up tomorrow with a bill for upload traffic spike. But it pretty much does its job as well as it could given quality of available data (OSM), so now I'm looking at…

If you hadn't already, I would have suggested vibe coding this.

I've done a different thing also with OSM data (isochrone rather than point-to-point routing) and put it on github to avoid needing to care about bandwidth on my domain, because also around ten megabytes for Berlin's data, despite having a step to convert JSON to a much more compact form with only the data I needed:

https://github.com/BenWheatley/Isochrone

https://benwheatley.github.io/Isochrone/web/?region=berlin&n...

Re: Hengefinder: Finding when the sun aligns with your street

#49

Post by fuzzfactor »

vritvo wrote: post #46
fuzzfactor wrote: post #6

It would be good to also have the option for alignment with sunrises in addition to sunsets. For instance in Houston the sunrise aligns with Texas Avenue around the June solstice. Consequently, there are no sunset alignments for the downtown skyscrapers.

Hello, thank you! That option already exists: On the website version, it's available in the "Henge Near Me" tab. You can toggle between Sunrise and Sunset. There are more features on the mobile version, and it also includes Sunrise and Sunset. Just hit the gear icon on the top right, and toggle between Sunrise and Sunset. Hope that helps!

This looks good and now I think my memory was about 180 degrees off, in Houston it must have been the winter solstice when I saw this one morning.

Your app gets very close but not quite there on the 22 DEC inflection point, I would think the date is correct but the angle is a couple degrees short when the limit is approached. At this latitude it looks like the effect is visible for a day or two before & after the closest alignment.

I'll be checking when the time comes but I was hoping it was only going to be a month from now :\

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