The above grid demonstrates an orthographic azimuthal projection. The lines are at uniform 10º increments of latitude and longitude.
Part 3 of 3.
- Orthographic Grid
- Orthographic Clipping
- Orthographic Shading
license: gpl-3.0 | |
redirect: https://observablehq.com/@d3/orthographic-shading |
The above grid demonstrates an orthographic azimuthal projection. The lines are at uniform 10º increments of latitude and longitude.
Part 3 of 3.
<!DOCTYPE html> | |
<meta charset="utf-8"> | |
<style> | |
circle, | |
path { | |
fill: none; | |
stroke: #123; | |
stroke-opacity: .5; | |
} | |
circle { | |
stroke-width: 2px; | |
} | |
</style> | |
<body> | |
<script src="//d3js.org/d3.v3.min.js"></script> | |
<script> | |
var width = 960, | |
height = 500; | |
var rotate = [-71.03, 42.37], | |
velocity = [.018, .006]; | |
var projection = d3.geo.orthographic() | |
.scale(240) | |
.clipAngle(90); | |
var path = d3.geo.path() | |
.projection(projection); | |
var graticule = d3.geo.graticule(); | |
var svg = d3.select("body").append("svg") | |
.attr("width", width) | |
.attr("height", height); | |
var gradient = svg.append("defs").append("radialGradient") | |
.attr("id", "gradient") | |
.attr("cx", "75%") | |
.attr("cy", "25%"); | |
gradient.append("stop") | |
.attr("offset", "5%") | |
.attr("stop-color", "#ffd"); | |
gradient.append("stop") | |
.attr("offset", "100%") | |
.attr("stop-color", "#ba9"); | |
var fill = svg.append("circle") | |
.attr("cx", width / 2) | |
.attr("cy", height / 2) | |
.attr("r", 240) | |
.style("fill", "url(#gradient)"); | |
var feature = svg.append("path") | |
.datum(graticule); | |
d3.timer(function(elapsed) { | |
projection.rotate([rotate[0] + elapsed * velocity[0], rotate[1] + elapsed * velocity[1]]); | |
fill.attr("transform", "rotate(" + (rotate[0] + elapsed * velocity[0]) + " " + width / 2 + "," + height / 2 + ")"); | |
feature.attr("d", path); | |
}); | |
</script> |