From: Scott Worley <ScottWorley@ScottWorley.com>
Date: Wed, 2 Jan 2013 07:44:02 +0000 (-0800)
Subject: Break out parts of go() into separate functions
X-Git-Url: http://git.scottworley.com/nt3d/commitdiff_plain/1378fd96ec4fe514d15de29575040bd78b896f2f?hp=0439f70af938c91e28bf00db0166979757eb428c

Break out parts of go() into separate functions

These things are useful separately, even to the point of including
nt3d.js into random other webpages via the javascript console as a
toolkit to manipulate and export stuff elsewhere on the web.
---

diff --git a/nt3d.js b/nt3d.js
index 7e0fa25..bc11c71 100644
--- a/nt3d.js
+++ b/nt3d.js
@@ -347,41 +347,20 @@ nt3d = {
 		       this.point_equal(b, c, this.degenerate_face_epsilon) ||
 		       this.point_equal(c, a, this.degenerate_face_epsilon);
 	},
-	go: function() {
-		// Remove any previous download links
-		var old_download_link = document.getElementById("nt3d_download");
-		if (old_download_link) {
-			old_download_link.parentNode.removeChild(old_download_link);
-		}
-
-		// Continue in a callback, so that there's not a stale download
-		// link hanging around while we process.
-		setTimeout(function(the_this) { (function() {
-
-		// Get params from form
-		var params = [];
-		for (var i = 0; i < this.user_params.length; i++) {
-			var as_string = this.form.elements["param"+i].value;
-			var as_num = +as_string;
-			params[i] = isNaN(as_num) ? as_string : as_num;
-		}
-
-		// Run user_function
-		this.points = this.user_function.apply(null, params);
-
+	validate: function(points) {
 		// Do a little validation
-		if (this.points.length % 3 != 0) {
+		if (points.length % 3 != 0) {
 			alert("Points list length not divisble by 3!");
 		}
 		var nan_count = 0;
 		var nan_point_count = 0;
 		var nan_face_count = 0;
-		for (var i = 0; i < this.points.length/3; i++) {
+		for (var i = 0; i < points.length/3; i++) {
 			var nan_in_face = false;
 			for (var j = 0; j < 3; j++) {
 				var nan_in_point = false;
 				for (var k = 0; k < 3; k++) {
-					if (isNaN(this.points[i*3+j][k])) {
+					if (isNaN(points[i*3+j][k])) {
 						nan_count++;
 						nan_in_point = true;
 						nan_in_face = true;
@@ -392,16 +371,17 @@ nt3d = {
 			if (nan_in_face) nan_face_count ++;
 		}
 		if (nan_count != 0) {
-			alert(nan_count + " NaNs in " + nan_point_count + " points in " + nan_face_count + " faces (" + (100 * nan_face_count / (this.points.length/3)) + "% of faces).");
+			alert(nan_count + " NaNs in " + nan_point_count + " points in " + nan_face_count + " faces (" + (100 * nan_face_count / (points.length/3)) + "% of faces).");
 		}
-
-		// Remove degenerate faces
+	},
+	remove_degenerate_faces: function(points) {
+		// Note: This modifies points
 		var degenerate_face_count = 0;
-		for (var i = 0; i < this.points.length/3; i++) {
-			if (this.is_degenerate(this.points[i*3+0], 
-			                       this.points[i*3+1], 
-			                       this.points[i*3+2])) {
-				this.points.splice(i*3, 3);
+		for (var i = 0; i < points.length/3; i++) {
+			if (this.is_degenerate(points[i*3+0], 
+			                       points[i*3+1], 
+			                       points[i*3+2])) {
+				points.splice(i*3, 3);
 				i--;
 				degenerate_face_count ++;
 			}
@@ -409,15 +389,16 @@ nt3d = {
 		if (degenerate_face_count != 0) {
 			console.log("Removed " + degenerate_face_count + " degenerate faces");
 		}
-
-		// Make STL
-		this.stl = "solid " + this.user_function.name + "\n";
-		for (var i = 0; i < this.points.length/3; i++) {
-			var a = this.points[i*3+0];
-			var b = this.points[i*3+1];
-			var c = this.points[i*3+2];
+		return points;
+	},
+	to_stl: function(points, name) {
+		var stl = "solid " + name + "\n";
+		for (var i = 0; i < points.length/3; i++) {
+			var a = points[i*3+0];
+			var b = points[i*3+1];
+			var c = points[i*3+2];
 			var normal = this.normal(a, b, c);
-			this.stl += "facet normal " + normal[0] + " " + normal[1] + " " + normal[2] + "\n" +
+			stl += "facet normal " + normal[0] + " " + normal[1] + " " + normal[2] + "\n" +
 				"outer loop\n" +
 				"vertex " + a[0] + " " + a[1] + " " + a[2] + "\n"+
 				"vertex " + b[0] + " " + b[1] + " " + b[2] + "\n"+
@@ -425,8 +406,35 @@ nt3d = {
 				"endloop\n" +
 				"endfacet\n";
 		}
-		this.stl += "endsolid " + this.user_function.name + "\n";
+		stl += "endsolid " + name + "\n";
+		return stl;
+	},
+	go: function() {
+		// Remove any previous download links
+		var old_download_link = document.getElementById("nt3d_download");
+		if (old_download_link) {
+			old_download_link.parentNode.removeChild(old_download_link);
+		}
+
+		// Continue in a callback, so that there's not a stale download
+		// link hanging around while we process.
+		setTimeout(function(the_this) { (function() {
+
+		// Get params from form
+		var params = [];
+		for (var i = 0; i < this.user_params.length; i++) {
+			var as_string = this.form.elements["param"+i].value;
+			var as_num = +as_string;
+			params[i] = isNaN(as_num) ? as_string : as_num;
+		}
+
+		this.points = this.user_function.apply(null, params);
+
+		this.validate(this.points);
+
+		this.remove_degenerate_faces(this.points);
 
+		this.stl = this.to_stl(this.points, this.user_function.name);
 
 		// Offer result as download
 		var download_link = document.createElement("a");