X-Git-Url: http://git.scottworley.com/nt3d/blobdiff_plain/ec5f883deb58becde856368829a76385c6e85470..0ee732b2898771d951a5dc4b79c1aaa3ce47b48b:/nt3d.js?ds=inline diff --git a/nt3d.js b/nt3d.js index 4cec096..a4d3977 100644 --- a/nt3d.js +++ b/nt3d.js @@ -46,8 +46,25 @@ nt3d = { closed_quadstrip: function(strip) { return this.quadstrip(strip.concat([strip[0], strip[1]])); }, - extrude: function(shape, path, shapenormals, pathnormals) { - var guts_result = nt3d._extrude_guts(shape, path, shapenormals, pathnormals); + circle: function(r, n) { + var points = []; + for (var i = 0; i < n; i++) { + points.push([r*Math.cos(2*Math.PI*i/n), + r*Math.sin(2*Math.PI*i/n), + 0]); + } + return points; + }, + cone: function(base_center, apex, radius, steps) { + var base = this.circle(radius, steps); + base = this.rotate_onto(base, [0,0,1], this.sub(apex, base_center)); + base = this.translate(base, base_center); + return this.closed_trianglefan([apex].concat(base)).concat( + this.trianglefan(base.reverse())); + }, + extrude: function(path, shape, shapenormals, pathnormals) { + + var guts_result = nt3d._extrude_guts(path, shape, shapenormals, pathnormals); // Add the end-caps // XXX: This doesn't work if shape is not convex return guts_result.points.concat( @@ -55,8 +72,8 @@ nt3d = { nt3d.trianglefan(guts_result.last_loop)); }, - closed_extrude: function(shape, path, shapenormals, pathnormals) { - var guts_result = nt3d._extrude_guts(shape, path, shapenormals, pathnormals); + closed_extrude: function(path, shape, shapenormals, pathnormals) { + var guts_result = nt3d._extrude_guts(path, shape, shapenormals, pathnormals); // Stitch the ends together return guts_result.points.concat( nt3d.closed_quadstrip(nt3d.zip(guts_result.first_loop, guts_result.last_loop))); @@ -72,7 +89,7 @@ nt3d = { } return fixedpathnormals; }, - _extrude_guts: function(shape, path, shapenormals, pathnormals) { + _extrude_guts: function(path, shape, shapenormals, pathnormals) { var fixedpathnormals = this._fix_pathnormals(shapenormals, pathnormals); var result = { points: [] }; var prev_loop; @@ -80,31 +97,25 @@ nt3d = { // loop is shape in 3d with (0,0) at path[i], shape's // z axis in the direction of shapenormals[i], and // shape's x axis in the direction of pathnormals[i]. - var loop = shape; + // We tack [1,0,0] onto the end as a hack to see where + // it ends up after rotation. This is removed later. + var loop = shape.concat([[1,0,0]]); // This is done in three steps: // 1. Rotate shape out of the xy plane so that [0,0,1] - // becomes shapenormals[i] by crossing [0,0,1] and - // shapenormals[i] to get a rotation axis and taking - // their dot product to get a rotation angle. This - // puts the shape in the correct plane, but does not - // constrain its rotation about shapenormals[i]. - var rot1axis = this.unit(this.cross([0,0,1], shapenormals[i])); - var rot1angle = this.angle_between([0,0,1], this.unit(shapenormals[i])); - if (rot1angle > 1e-7) { - loop = this.rotate_about_origin(loop, rot1axis, rot1angle); - } + // becomes shapenormals[i]. This puts the shape in + // the correct plane, but does not constrain its + // rotation about shapenormals[i]. + loop = this.rotate_onto(loop, [0,0,1], shapenormals[i]); + var shapex = loop.pop(); // 2. Rotate around shapenormals[i] so that [1,0,0] // becomes fixedpathnormals[i]. - var rot2axis = this.unit(shapenormals[i]); - var rot2angle = this.angle_between([1,0,0], this.unit(fixedpathnormals[i])); - if (rot2angle > 1e-7) { - loop = this.rotate_about_origin(loop, rot2axis, rot2angle); - } - // This would probably be faster and more numerically stable + loop = this.rotate_onto(loop, shapex, fixedpathnormals[i]); + + // (This would probably be faster and more numerically stable // if the two rotations were applied as one combined operation - // rather than separate steps. + // rather than separate steps.) // 3. Translate to path[i]. loop = this.translate(loop, path[i]); @@ -188,6 +199,19 @@ nt3d = { } return rotated; }, + rotate_onto: function(points, a, b) { + // Rotate points such that a (in points-space) maps onto b + // by crossing a and b to get a rotation axis and using + // angle_between to get a rotation angle. + var angle = this.angle_between(this.unit(a), this.unit(b)); + if (Math.abs(angle) < 1e-15) { + // No siginificant rotation to perform. Bail to avoid + // NaNs and numerical error + return points; + } + var axis = this.unit(this.cross(a, b)); + return this.rotate_about_origin(points, axis, angle); + }, rotate: function(points, center, axis, angle) { // axis must be a unit vector return this.translate( this.rotate_about_origin( @@ -197,6 +221,16 @@ nt3d = { center); }, 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++) { @@ -229,11 +263,6 @@ nt3d = { } this.stl += "endsolid " + this.user_function.name + "\n"; - // 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); - } // Offer result as download var download_link = document.createElement("a"); @@ -244,6 +273,8 @@ nt3d = { download_link.setAttribute("href", "data:application/sla," + encodeURIComponent(this.stl)); this.ui.appendChild(download_link); setTimeout(function() { download_link.setAttribute("style", "-webkit-transition: background-color 0.4s; -moz-transition: background-color 0.4s; -o-transition: background-color 0.4s; -ms-transition: background-color 0.4s; transition: background-color 0.4s; background-color: inherit"); }, 0); + + }).call(the_this); }, 0, this); // (We were in a callback this whole time, remember?) }, framework: function (f, params) { this.user_function = f;