From: Scott Worley Date: Sat, 29 Dec 2012 08:08:19 +0000 (-0800) Subject: Remove degenerate faces X-Git-Url: http://git.scottworley.com/nt3d/commitdiff_plain/6e5e17591a2a5adac5e4ec016c7bad71505b1e64 Remove degenerate faces --- diff --git a/nt3d.js b/nt3d.js index 33e271b..3ce05be 100644 --- a/nt3d.js +++ b/nt3d.js @@ -297,6 +297,17 @@ nt3d = { angle), center); }, + point_equal: function(a, b, epsilon) { + return Math.abs(a[0] - b[0]) < epsilon && + Math.abs(a[1] - b[1]) < epsilon && + Math.abs(a[2] - b[2]) < epsilon; + }, + degenerate_face_epsilon: 1e-10, + is_degenerate: function(a, b, c) { + return this.point_equal(a, b, this.degenerate_face_epsilon) || + 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"); @@ -323,11 +334,10 @@ nt3d = { if (this.points.length % 3 != 0) { alert("Points list length not divisble by 3!"); } - var n = this.points.length / 3; var nan_count = 0; var nan_point_count = 0; var nan_face_count = 0; - for (var i = 0; i < n; i++) { + for (var i = 0; i < this.points.length/3; i++) { var nan_in_face = false; for (var j = 0; j < 3; j++) { var nan_in_point = false; @@ -346,9 +356,24 @@ nt3d = { alert(nan_count + " NaNs in " + nan_point_count + " points in " + nan_face_count + " faces."); } + // Remove degenerate faces + 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); + i--; + degenerate_face_count ++; + } + } + 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 < n; i++) { + 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];