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> |