Add "direction" to viewpoint and other POIs

[nvkelso]

OSM allows the direction to be set on viewpoints and other POIs, and Tangram can orient icons.

• https://wiki.openstreetmap.org/wiki/Tag:tourism%3Dviewpoint
• https://taginfo.openstreetmap.org/tags/?key=tourism&value=viewpoint
• https://wiki.openstreetmap.org/wiki/Key:direction
• https://taginfo.openstreetmap.org/keys/direction

[nvkelso]

Looks like ~1000 of the 86,000 node features have direction, says TagInfo.

Direction values need to be normalized to degrees (°), sometimes they come in form of north or N or NE, see below.

Probably needs a TileStashe transform to ensure:

• Number should be in range of 0-359, where 0 is equal to north, using a clockwise rotation.
• Cardinal values (N, W, S, E, NE, NW, SE, and SW) are converted to their ° int values.

[nvkelso]

Lookup for cardinal > degrees from OSM wiki:

[nvkelso]

Tangram supports setting an angle on icons now, let's add this to tiles!

/cc @dmvaldman.

[dmvaldman]

Since Tangram support angles on icons, is the part that needs implementing on the Tangram side the conversion of cardinal values to degrees?

[nvkelso]

I think that conversion should be on Tilezen, not Tangram. So as long as Tangram supports sourcing the angle value from a feature property, &/or a function, we should be good on your side.

…

On Tue, Mar 7, 2017 at 5:09 PM, David Valdman ***@***.***> wrote: Since Tangram support angles on icons, is the part that needs implementing on the Tangram side the conversion of cardinal values to degrees? — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#598 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AA0EOznTRXuzvTUWDshhvaojo876tf-gks5rjf_UgaJpZM4Hvbei> .

[nvkelso]

Let's use a consistent property name as #1219 (direction versus angle).

[nvkelso]

Here's a fun one, backward pointing stop signs:

• https://www.openstreetmap.org/node/3477023168