return this.closed_trianglefan([apex].concat(base)).concat(
this.trianglefan(base.reverse()));
},
+ sphere: function(center, radius, latitude_steps, longitude_steps) {
+ return this.oriented_sphere(center, radius, [0,0,1], [1,0,0], latitude_steps, longitude_steps);
+ },
+ oriented_sphere: function(center, radius, north, greenwich, latitude_steps, longitude_steps) {
+ var unit_north = this.unit(north);
+ var north_pole = this.translate_point(this.scale(unit_north, radius), center);
+ var south_pole = this.translate_point(this.scale(unit_north, -radius), center);
+ return this.spheroid(north_pole, south_pole, radius, greenwich, latitude_steps, longitude_steps);
+ },
+ spheroid: function(north_pole, south_pole, radius, greenwich, latitude_steps, longitude_steps) {
+ var delta = this.sub(north_pole, south_pole);
+ var path = [];
+ for (var i = 0; i < latitude_steps-1; i++) {
+ path.push(this.translate_point(south_pole, this.scale(delta, (1-Math.cos(Math.PI*i/(latitude_steps-1)))/2)));
+ }
+ path.push(north_pole);
+ function shape(i) {
+ return nt3d.circle(radius*Math.sin(Math.PI*i/(latitude_steps-1)), longitude_steps);
+ }
+ return this.extrude(path, shape, delta, greenwich);
+ },
shapenormals_from_closed_path: function(path) {
return function(i) {
var prev = (i == 0) ? path.length-1 : i-1;
--- /dev/null
+<html>
+ <head>
+ <title>Sphere primitive</title>
+ <script type="text/javascript" src="nt3d.js"></script>
+ <script type="text/javascript">
+ function sphere_primitive(radius, lattitude_steps, longitude_steps) {
+ return nt3d.sphere([0,0,0], radius, lattitude_steps, longitude_steps);
+ }
+ var params = [["Radius", 1],
+ ["Lattitude steps", 20],
+ ["Longitude steps", 20]];
+ </script>
+ </head>
+ <body onload="nt3d.framework(sphere_primitive, params)">
+ <h1>Sphere primitive</h1>
+ <p>There's a sphere primitive.</p>
+ </body>
+</html>
projects / nt3d / commitdiff