Reflection Tealight

thingiverse

This is a tealight created with ShapeJS. Sized to accept standard LED lights. The code takes an image and tiles it around a sphere to make interesting patterns. Instructions Goto shapejs.shapeways.com and use this code. It takes one file parameter which is the image to tile around the sphere. // // Tealight example using polyhedra reflection // // author Vladimir Bulatov // author Alan Hudson // var TAU = (Math.sqrt(5)+1)/2; // golden ratio var PI = Math.PI; // Returns plane via 3 points (v1, 0, v2) // external normal points in the direction from where points are ordered counter clockwise function getPlane(v1,v2){ var n = new Vector3d(); n.cross(v2,v1); n.normalize(); return ReflectionSymmetry.getPlane(n, 0); } function getIcosahedralSymmetry( ){ var v5 = new Vector3d(1,0,TAU); // vertex of icosahedron var v3 = new Vector3d(0,1/TAU,TAU); // vertex of dodecahedron var p35 = new Vector3d(); // normal to plane via (0, v3, v5) p35.cross(v3, v5); p35.normalize(); var splanes = new Array(); var count = 0; splanes[count++] = new ReflectionSymmetry.getPlane(new Vector3d(-1,0,0), 0.); splanes[count++] = new ReflectionSymmetry.getPlane(new Vector3d(0,-1,0), 0.); splanes[count++] = new ReflectionSymmetry.getPlane(p35, 0.); return new ReflectionSymmetry(splanes); } function getSphereBend(fixedRadius, bendAmount, offset){ var center = fixedRadius*fixedRadius/bendAmount; var radius = Math.sqrt(center*center + fixedRadius*fixedRadius); var cp = new CompositeTransform(); cp.add(new PlaneReflection(new Vector3d(0,0,1), new Vector3d(0,0,offset))); cp.add(new SphereInversion(new Vector3d(0,0,-center + offset), radius)); return cp; } function getImage(radius, thickness, path){ var s = radius/Math.sqrt(1 + 1./(TAU*TAU)); var v5 = new Vector3d(s/TAU,0,s); // vertex of icosahedron var v3 = new Vector3d(0,s/(TAU*TAU),s); // vertex of dodecahedron var union = new Union(); var correction = 1.1; // correction to get var ypnt = v3.y*correction; var xpnt = v5.x; var image = new ImageBitmap(path, xpnt, ypnt, thickness); var vs = 0.1*MM; image.setBaseThickness(0); image.setVoxelSize(vs); image.setUseGrayscale(false); image.setBlurWidth(vs); image.setTransform(new Translation(xpnt/2,ypnt/2,v5.z)); union.add(image); union.setTransform(getSphereBend(v5.x, radius - v5.z, v5.z)); var dt = new DataTransformer(); dt.setSource(union); return dt; } // Create a hole for the tea light to be placed through function getLightHole(hole,outside) { var cyl = new Cylinder(new Vector3d(0,0,0), new Vector3d(0,-outside,0), hole); return cyl; } // Create a rim around the light hole function getRim(hole,radius,thickness) { var cr = hole + thickness; // Calculate intersection location of cylinder with sphere var loc = -radius +(radius - Math.sqrt(radius * radius - cr * cr)) - thickness; var outer = new Cylinder(new Vector3d(0,loc,0), new Vector3d(0,loc-thickness,0), hole + thickness); var inner = new Cylinder(new Vector3d(0,loc,0), new Vector3d(0,loc-thickness,0), hole); var rim = new Subtraction(outer,inner); return rim; } function main(arg){ var radius = 31.1*MM; var thickness = 1.0*MM; var voxelSize = 0.2*MM; var holeRadius = 20*MM; // a bit larger then a typical 1.5" / 38.1mm tea light var rimThickness = 1.25*MM; var a = radius + 2*thickness; var path = arg[0]; var image = getImage(radius,thickness, path,voxelSize); var reflectedImage = new Union(); reflectedImage.add(image); reflectedImage.setTransform(getIcosahedralSymmetry( )); var subtract = new Subtraction(reflectedImage, getLightHole(holeRadius,a)); var rim = getRim(holeRadius,radius,rimThickness); var tealight = new Union(subtract, rim); var maker = new GridMaker(); maker.setSource(tealight); var dest = createGrid(-a,a,-a,a,-a,a,voxelSize); maker.makeGrid(dest); return dest; }