The avatar for @jjhembd
Jeshurun Hembd
I want to help more people experience the excitement of exploring Earth's subsurface
Published
Edited
Aug 3, 2019
1 fork
7 stars
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visibleYextent = 2 * altitude * Math.tan(0.5 * fieldOfView * Math.PI / 180)
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scale = earthRadius * numPixelsY / visibleYextent;
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snyderP = 1 + altitude / earthRadius;
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projection = d3.geoSatellite()
.translate([width / 2, numPixelsY / 2])
.scale(scale)
.rotate([-longitude, -latitude, 0])
.distance(snyderP)
.clipAngle(Math.acos(1 / snyderP) * 180 / Math.PI)
.precision(0.1);
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numPixelsY = width * 0.6;
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earthRadius = 6371; // Spherical approximation: average radius in km
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horizon = ({type: "Sphere"})
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graticuleMinor = d3.geoGraticule().step([5,5])()
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graticuleMajor = d3.geoGraticule().step([15,15])()
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land = topojson.feature(world, world.objects.land)
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world = fetch("https://cdn.jsdelivr.net/npm/world-atlas@1/world/50m.json").then(response => response.json())
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topojson = require("topojson-client@3")
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import {number} from "@jashkenas/inputs"
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d3 = require("d3-geo@1", "d3-geo-projection@2")
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