Map Scale (ie, representative fraction)

[jfuehner]

Hi all! Does deck provide a way to get the map scale and/or corresponding representative fraction based on the current zoom level?

Or… Will it need to be calculate manually? Perhaps using the WebMercatorViewport?

Thanks!

[Pessimistress]

Scale is 2 ** zoom

[jfuehner]

@Pessimistress I think I am following your response.

In terms of calculating the RF from the scale (2**zoom). Assuming I have 256x256 tiles I could calculate total meters per pixels…

equatorCircumferenceMeters = 40_075_000
zoom = 0
mapWidthPixels = ( 256 * (2**zoom) ) = 256
scalePerPixel = (equatorCircumferenceMeters / mapWidthPixels) = 156_543
metersPerPixel = (1 / scalePerPixel)

RF = 1:metersPerPixel (ie, 1:156_543)

I am probably way off… Or perhaps overly complicating it.