From: Scott Worley <ScottWorley@ScottWorley.com>
Date: Tue, 18 Dec 2012 09:34:16 +0000 (-0800)
Subject: Triangle fans
X-Git-Url: http://git.scottworley.com/nt3d/commitdiff_plain/0ab5ca18fc7c4d26a3a7cf30cd902d2ebc190f4d
Triangle fans
---
diff --git a/box_by_trianglefan.html b/box_by_trianglefan.html
new file mode 100644
index 0000000..1972560
--- /dev/null
+++ b/box_by_trianglefan.html
@@ -0,0 +1,27 @@
+<html>
+ <head>
+ <title>Box by trianglefan</title>
+ <script type="text/javascript" src="nt3d.js"></script>
+ <script type="text/javascript">
+ function box_by_trianglefan(size_as_string) {
+ var size = parseFloat(size_as_string);
+ var origin = [0, 0, 0 ];
+ var x = [size, 0, 0 ];
+ var y = [0, size, 0 ];
+ var z = [0, 0, size];
+ var xy = [size, size, 0 ];
+ var xz = [size, 0, size];
+ var yz = [0, size, size];
+ var xyz = [size, size, size];
+ return [].concat(
+ nt3d.trianglefan([origin, x, xz, z, yz, y, xy, x]),
+ nt3d.trianglefan([xyz, yz, z, xz, x, xy, y, yz]));
+ }
+ var params = [["Size", 1]];
+ </script>
+ </head>
+ <body onload="nt3d.framework(box_by_trianglefan, params)">
+ <h1>Box by trianglefan</h1>
+ <p>Make a box with two triangle fans from opposite corners.</p>
+ </body>
+</html>
diff --git a/nt3d.js b/nt3d.js
index ba2315f..623c0f1 100644
--- a/nt3d.js
+++ b/nt3d.js
@@ -23,6 +23,13 @@ nt3d = {
return this.triangle(a, b, c).concat(
this.triangle(c, d, a));
},
+ trianglefan: function(fan) {
+ var result = [];
+ for (var i = 2; i < fan.length; i++) {
+ result.push(fan[0], fan[i-1], fan[i]);
+ }
+ return result;
+ },
quadstrip: function(strip) {
if (strip.length % 2 != 0) {
alert("quadstrip length not divisble by 2!");