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Nicolas Lambert
Hi. I'm Nicolas Lambert, research engineer in geographic information science at CNRS (France). My job is to draw maps and teach cartography at the university. I am a geographer 🌎, and not really a developer 🖥️
Public
Geographic libraries
Edited
Jun 20, 2023
2 stars
1
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proj4 = require("proj4")
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firstProjection = 'PROJCS["NAD83 / Massachusetts Mainland",GEOGCS["NAD83",DATUM["North_American_Datum_1983",SPHEROID["GRS 1980",6378137,298.257222101,AUTHORITY["EPSG","7019"]],AUTHORITY["EPSG","6269"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.01745329251994328,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4269"]],UNIT["metre",1,AUTHORITY["EPSG","9001"]],PROJECTION["Lambert_Conformal_Conic_2SP"],PARAMETER["standard_parallel_1",42.68333333333333],PARAMETER["standard_parallel_2",41.71666666666667],PARAMETER["latitude_of_origin",41],PARAMETER["central_meridian",-71.5],PARAMETER["false_easting",200000],PARAMETER["false_northing",750000],AUTHORITY["EPSG","26986"],AXIS["X",EAST],AXIS["Y",NORTH]]'
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secondProjection = "+proj=gnom +lat_0=90 +lon_0=0 +x_0=6300000 +y_0=6300000 +ellps=WGS84 +datum=WGS84 +units=m +no_defs"
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proj4(firstProjection, secondProjection, [-122.305887, 58.9465872, 10])
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proj4(secondProjection, [-71, 41])
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transform = proj4(firstProjection, secondProjection)
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transform.forward([-71, 41])
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transform.inverse([-2690599.9886444192, 3662814.7663661353])
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proj4.defs([
[
"EPSG:4326",
"+title=WGS 84 (long/lat) +proj=longlat +ellps=WGS84 +datum=WGS84 +units=degrees"
],
[
"EPSG:4269",
"+title=NAD83 (long/lat) +proj=longlat +a=6378137.0 +b=6356752.31414036 +ellps=GRS80 +datum=NAD83 +units=degrees"
]
])
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proj4("EPSG:4326")
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proj4("EPSG:4326").oProj
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world = d3
.json(
"https://cdn.jsdelivr.net/npm/visionscarto-world-atlas@0.1.0/world/110m.json"
)
.then((d) => topojson.feature(d, d.objects.countries))
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bertin = require("bertin")
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bertin.draw({
params: { projection: prj },
layers: [
{ geojson: world, fill: "#909ede" },
{ type: "graticule" },
{ type: "outline" }
]
})
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d3 = require("d3", "d3-geo-projection")
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import { proj4d3 } from "@fil/proj4js-d3"
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worldMollweide = d3.geoProject(world, proj4d3(prj).reflectY(true))
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button(worldMollweide, "worldMollowoide.geojson")
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bertin.draw({
params: { projection: "user" },
layers: [{ geojson: worldMollweide, fill: "#909ede" }]
})
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