OpenJsCad demo: Parametric Lamp Shade

Source code

Below is the OpenJsCad script for this demo. To build your own models, create a .jscad script and use the OpenJsCad parser. For more information see the OpenJsCad documentation.

function main(params)
{
  CSG.defaultResolution2D = (params.quality == "DRAFT")? 8:32;

var bottomradius = params.bottomdiameter/2;
  var topradius = params.topdiameter/2;
  var height = params.height;
  var numfaces = params.numfaces;
  var thickness = params.thickness;
  var topholeradius = params.topholediameter/2;
  var cutterRadius = params.cutterdiameter / 2;
  
  var solid = CSG.cube({radius: [1000, 1000, height/2]});
  
  var plane = CSG.Plane.fromPoints([bottomradius, 0, -height/2], [bottomradius, 10, -height/2], [topradius, 0, height/2]);
  for(var i = 0; i < numfaces; i++)
  {
    solid = solid.cutByPlane(plane.rotateZ(i * 360 / numfaces));
  }

var plates = solidToOuterShellPlates(solid, thickness);
  plates = removePlateWithNormal(plates, [0,0,-1]);
  plates = removePlateWithNormal(plates, [0,0,1]);

for(var i = 1; i < numfaces; i++)
  {
    plates[i] = plates[0].rotateZ(i * 360 / numfaces);
  }
  
  var topplate = getStockPlate(1000,1000,thickness)
    .subtract(CSG.cylinder({start: [0,0,-thickness], end:[ 0,0,thickness], radius: topholeradius}))
    .translate([0,0,height/2-thickness/2-10]);
  topplate = topplate.intersect(solid);
  topplate = fixPlate(topplate, thickness);

var fingerjointoptions = {
    margin: 0, cutterRadius: cutterRadius, fingerWidth: 25
  };
  plates = fingerJoint(plates,fingerjointoptions);
  plates = fingerJointAdd(plates, topplate, fingerjointoptions);

if(params.type == "TOPPLATE")
  {
    return plateCSGToCAG(plates[numfaces]);
  }
  else
  {  
    var plate2d = plateCSGToCAG(plates[0]);
    plate2d = addRandomHoles(plate2d); 
    if(params.type == "SIDEPLATE")
    {
      return plate2d;
    }
    else
    {
      for(var i = 0; i < numfaces; i++)
      {
        var plate3d =  plateCAGToCSG(plate2d, plates[i].properties.platebasis, thickness);
        plates[i] = plate3d;
      }
      var result = new CSG().union(plates);
      result = result.rotateX(90);
      return result;
    }
  }
}

function plateCSGToCAG(plate)
{
  if(!("platebasis" in plate.properties))
  {
    throw new Error("Plates should be created using getStockPlate()");
  }
  var plate2d = plate.projectToOrthoNormalBasis(plate.properties.platebasis);
  return plate2d;
}

function plateCAGToCSG(plate2d, platebasis, thickness)
{
  var basisinversematrix = platebasis.getInverseProjectionMatrix();
  var plate_reprojected = plate2d.extrude({offset: [0,0,thickness]}).translate([0,0,-thickness/2]);
  plate_reprojected = plate_reprojected.transform(basisinversematrix);
  plate_reprojected.properties.platebasis = platebasis;
  return plate_reprojected;
}

function fixPlate(plate, thickness)
{
  return plateCAGToCSG(plateCSGToCAG(plate), plate.properties.platebasis, thickness); 
}

function getStockPlate(width, height, thickness)
{
  var result = CSG.cube({radius: [width/2, height/2, thickness/2]});
  result.properties.platebasis = CSG.OrthoNormalBasis.Z0Plane();
  return result;
}

function fingerJointAdd(plates, newplate, options)
{
  var result = plates.slice(0);
  var numplates = plates.length;
  for(var plateindex1 = 0; plateindex1 < numplates; plateindex1++)
  {
    var joined = fingerJointTwo(result[plateindex1], newplate, options);
    result[plateindex1] = joined[0];
    newplate = joined[1];
  }
  result.push(newplate);
  return result;
}

// Finger joint between multiple plates:
function fingerJoint(plates, options)
{
  var result = plates.slice(0);
  var numplates = plates.length;
  var maxdelta = Math.floor(numplates/2);
  for(var delta=1; delta <= maxdelta; delta++)
  { 
    for(var plateindex1 = 0; plateindex1 < numplates; plateindex1++)
    {
      var plateindex2 = plateindex1 + delta;
      if(plateindex2 >= numplates) plateindex2 -= numplates; 
      
      var joined = fingerJointTwo(result[plateindex1], result[plateindex2], options);
      result[plateindex1] = joined[0];
      result[plateindex2] = joined[1];
      if(delta*2 >= numplates)
      {
        // numplates is even
        if(plateindex1*2 >= numplates)
        {
          // and we've done the first half: we're done
          break;
        }
      }
    }
  }
  return result;
}

// Create a rectangular cutout in 2D
// minx, miny, maxx, maxy: boundaries of the rectangle
// cutterRadius: if > 0, add extra cutting margin at the corners of the rectangle
// plate2d is the 2d shape from which the cutout will be subtracted
// it is tested at the corners of the cutout rectangle, to see if do need to add the extra margin at that corner
function createRectCutoutWithCutterRadius(minx, miny, maxx, maxy, cutterRadius, plate2d)
{
  var deltax = maxx-minx;
  var deltay = maxy-miny;  
  var cutout = CAG.rectangle({radius: [(maxx-minx)/2, (maxy-miny)/2], center: [(maxx+minx)/2, (maxy+miny)/2]});
  var cornercutouts = [];
  if(cutterRadius > 0)
  {
    var extracutout = cutterRadius * 0.2;
    var hypcutterradius = cutterRadius / Math.sqrt(2.0);
    var halfcutterradius = 0.5 * cutterRadius;
    var dcx, dcy;
    if(deltax > 3*deltay)
    {
      dcx = cutterRadius + extracutout/2;
      dcy = extracutout / 2;
    }
    else if(deltay > 3*deltax)
    {
      dcx = extracutout / 2;
      dcy = cutterRadius + extracutout/2;
    }
    else
    {
      dcx = hypcutterradius-extracutout/2;
      dcy = hypcutterradius-extracutout/2;
    }
    for(var corner = 0; corner < 4; corner++)
    {
      var cutoutcenterx = (corner & 2)? (maxx-dcx):(minx+dcx);
      var cutoutcentery = (corner & 1)? (maxy-dcy):(miny+dcy);
      var cornercutout = CAG.rectangle({radius: [cutterRadius+extracutout/2, cutterRadius+extracutout/2], center: [cutoutcenterx, cutoutcentery]});
      var testrectacenterx = (corner & 2)? (maxx-halfcutterradius):(minx+halfcutterradius);
      var testrectbcenterx = (corner & 2)? (maxx+halfcutterradius):(minx-halfcutterradius);
      var testrectacentery = (corner & 1)? (maxy+halfcutterradius):(miny-halfcutterradius);
      var testrectbcentery = (corner & 1)? (maxy-halfcutterradius):(miny+halfcutterradius);
      var testrecta = CAG.rectangle({radius: [halfcutterradius, halfcutterradius], center: [testrectacenterx, testrectacentery]}); 
      var testrectb = CAG.rectangle({radius: [halfcutterradius, halfcutterradius], center: [testrectbcenterx, testrectbcentery]});
      if( (plate2d.intersect(testrecta).sides.length > 0)  
       && (plate2d.intersect(testrectb).sides.length > 0) )
      {
        cornercutouts.push(cornercutout);
      }
    }
  }
  if(cornercutouts.length > 0)
  {
    cutout = cutout.union(cornercutouts);
  } 
  return cutout;
}

function getParameterDefinitions()
{
  return [
    {name: 'topdiameter', type: 'float', default: 160, caption: "Top diameter:"},
    {name: 'bottomdiameter', type: 'float', default: 300, caption: "Bottom diameter:"},
    {name: 'height', type: 'float', default: 170, caption: "Height:"},
    {name: 'numfaces', type: 'int', default: 5, caption: "Number of faces:"},
    {name: 'thickness', type: 'float', default: 4, caption: "Thickness of stock material:"},
    {name: 'topholediameter', type: 'float', default: 42, caption: "Diameter of top hole:"},
    {name: 'cutterdiameter', type: 'float', default: 3.2, caption: "Diameter of CNC cutter / laser beam:"},

{
      name: 'type',
      type: 'choice',
      values: ["ASSEMBLED", "TOPPLATE", "SIDEPLATE"],               // these are the values that will be supplied to your script
      captions: ["Assembled", "Top plate (DXF output)", "Side plate (DXF output)"],  // optional, these values are shown in the listbox
                                                   // if omitted, the items in the 'values' array are used
      caption: 'Show:',                           // optional, displayed left of the input field
      default: "ASSEMBLED",                              // optional, default selected value
                                                   // if omitted, the first item is selected by default
    },
    {
      name: 'quality',
      type: 'choice',
      values: ["DRAFT", "HIGH"],               // these are the values that will be supplied to your script
      captions: ["Draft", "High"],  // optional, these values are shown in the listbox
                                                   // if omitted, the items in the 'values' array are used
      caption: 'Quality:',                           // optional, displayed left of the input field
      default: "DRAFT",                              // optional, default selected value
                                                   // if omitted, the first item is selected by default
    },

];
}