MVTLayer + ArcLayer

[hyundotio]

Hello,

I am a noobie when it comes to Deck, so I apologize in advance if this question is outright stupid heh.

I'm trying to create a ArcLayer (as a sublayer) from Mapbox Tiles (MVTLayer). When I assign getSourceColor and getTargetColor it starts and ends at tile seams, not the actual beginning + end. This lead me to believe that the object coordinates are localized to tiles. And when I logged the object, that seemed to be the case.

I tried searching and searching and the closest thing I've gotten to was a thread that mentions MVT Loader / Loader Options, and some parameters (modelMatrix, coordinateSystem, coordinateOrigin, clipBounds)... but I had no luck in getting the result I want (a single line that has getSourceColor -> getTargetColor, rather than repeating gradient per tile).

Any help or pointers would be appreciated.

Thank you.

[kylebarron]

Vector tiles are tiled, which means that every tile is loaded and rendered independently. In order to correctly render the ArcLayer, you'd need to find a way to find the actual start and end point of each arc. It would probably be considerably easier to do this without storing the data as vector tiles.

[kylebarron]

You'd have to do something like store a unique index for each start-end pair, but it's not generally possible because you have no idea that start and end are in the viewport.

[Pessimistress]

You can also use an IconLayer to place an arrow at the midpoint of the line segment.

[hyundotio]

@Pessimistress, this means I'd have to calculate the midpoint using the 2 localized coordinates then figure out the angle/rotation too correct?

[Pessimistress]

The localized coordinates are already in cartesian space, so the midpoint will be [(x0+x1)/2, (y0+y1)/2] and the rotation will be Math.atan2(y1-y0, x1-x0).

[hyundotio]

@Pessimistress Thank you. Then the Math.atan2(y1-y0, x1-x0) would be that * 180 / Pi - correct?

(Math.atan2(y1-y0, x1-x0) * 180) / Pi

Cheers!