Please note: OpenJsCad currently only runs reliably on Google Chrome!
Create an STL file for 3D printing using constructive solid modeling in Javascript.
Playground
Try it by entering some code below. Anything you enter will be lost as soon as this page is reloaded;
to build your own models you should instead store them in a .jscad file on your computer
and use the OpenJsCad parser.
About
This is intended to become a Javascript based alternative to OpenSCAD,
for 3D solid modeling.
CSG model is contructed using Javascript. For example: var cube = CSG.cube(); return cube; creates a cube with a radius of 1 and centered at the origin.
The code should always end in a return statement, returning a CSG solid.
To build your own modes, create a .jscad file with your javascript code and parse the file using the
OpenJsCad parser. When finished you can generate an .stl file,
ready to be printed on your 3d printer.
License
Copyright (c) 2012 Joost Nieuwenhuijse.
Uses CSG.js, original copyright (c) 2011 Evan Wallace,
extensively modified, copyright (c) 2012 Joost Nieuwenhuijse.
Uses lightgl.js by Evan Wallace for WebGL rendering.
All code released under MIT license.
Contributions are welcome! It's all written in Javascript, so if you know how to use it you
know how to modify it as well.
Click and drag to rotate the model around the origin.
Shift+Drag moves the model around.
Alt+drag zooms (by changing the distance between camera and model).
Primitive solids
Currently the following solids are supported. The parameters are passed in an object; most
parameters are optional. 3D vectors can be passed in an array. If a scalar is passed
for a parameter which expects a 3D vector, it is used for the x, y and z value.
In other words: radius: 1 will give radius: [1,1,1].
All rounded solids have a 'resolution' parameter which controls tesselation. If resolution
is set to 8, then 8 polygons per 360 degree of revolution are used. Beware that rendering
time will increase dramatically when increasing the resolution. For a sphere the number of polygons
increases quadratically with the resolution used.
// a cube:
var cube = CSG.cube({
center: [0, 0, 0],
radius: [1, 1, 1]
});
// a sphere:
var sphere = CSG.sphere({
center: [0, 0, 0],
radius: 2, // must be scalar
resolution: 32
});
// a cylinder:
var cylinder = CSG.cylinder({
start: [0, -1, 0],
end: [0, 1, 0],
radius: 1,
resolution: 16
});
// like a cylinder, but with spherical endpoints:
var roundedCylinder = CSG.roundedCylinder({
start: [0, -1, 0],
end: [0, 1, 0],
radius: 1,
resolution: 16
});
// a rounded cube:
var cube = CSG.roundedCube({
center: [0, 0, 0],
radius: 1,
roundradius: 0.2,
resolution: 8,
});
CSG operations
The 3 standard CSG operations are supported. All CSG operations return a new solid; the source solids
are not modified:
var csg1 = cube.union(sphere);
var csg2 = cube.intersect(sphere);
var csg3 = cube.subtract(sphere);
Transformations
Solids can be translated, scaled and rotated. Multiple transforms can be combined into a single matrix transform:
var cube = CSG.cube();
// translation:
var cube2 = cube.translate([1, 2, 3]);
// scaling:
var largecube = cube.scale(2.0);
var stretchedcube = cube.scale([1.5, 1, 0.5]);
// rotation:
var rotated1 = cube.rotateX(-45); // rotate around the X axis
var rotated2 = cube.rotateY(90); // rotate around the Y axis
var rotated3 = cube.rotateZ(20); // rotate around the Z axis
// combine multiple transforms into a single matrix transform:
var m = new CSG.Matrix4x4();
m = m.multiply(CSG.Matrix4x4.rotationX(40));
m = m.multiply(CSG.Matrix4x4.rotationZ(40));
m = m.multiply(CSG.Matrix4x4.translation([-.5, 0, 0]));
m = m.multiply(CSG.Matrix4x4.scaling([1.1, 1.2, 1.3]));
// and apply the transform:
var cube3 = cube.transform(m);
Expansion and contraction
Expansion can be seen
as the 3D convolution of an object with a sphere. Contraction is the reverse: the area outside the solid
is expanded, and this is then subtracted from the solid.
Expansion and contraction are very powerful ways to get an object with nice smooth corners. For example
a rounded cube can be created by expanding a normal cube.
Note that these are expensive operations: spheroids are created around every corner and edge in the original
object, so the number of polygons quickly increases. Expansion and contraction therefore are only practical for simple
non-curved objects.
expand() and contract() take two parameters: the first is the radius of expansion or contraction; the second
parameter is optional and specififies the resolution (number of polygons on spherical surfaces, per 360 degree revolution).
var cube1 = CSG.cube({radius: 1.0});
var cube2 = CSG.cube({radius: 1.0}).translate([-0.3, -0.3, -0.3]);
var csg = cube1.subtract(cube2);
var rounded = csg.expand(0.2, 8);
Determining the bounds of an object
The getBounds() function can be used to retrieve the bounding box of an object.
This can be useful if you want to align two objects to each other. getBounds() returns
an array with two elements specifying the minimum x,y,z coordinate and the maximum x,y,z coordinate:
var cube1 = CSG.cube({radius: 10});
var cube2 = CSG.cube({radius: 5});
// get the right bound of cube1 and the left bound of cube2:
var deltax = cube1.getBounds()[1].x - cube2.getBounds()[0].x;
// align cube2 so it touches cube1:
cube2 = cube2.translate([deltax, 0, 0]);
return cube1.union(cube2);
2D shapes
Two dimensional shapes can be defined through the Polygon2D class. Currently this requires the polygon to be convex
(i.e. all corners less than 180 degrees). Shapes can be transformed (rotation, translation, scaling).
To actually use the shape it needs to be extruded into a 3D CSG object through the extrude() function. extrude()
places the 2D solid onto the z=0 plane, and extrudes in the specified direction. Extrusion can be done with an optional
twist. This rotates the solid around the z axis (and not necessariy around the extrusion axis) during extrusion.
The total degrees of rotation is specified in the twistangle parameter, and twiststeps determine the number of steps
between the bottom and top surface.
// Create a shape; argument is an array of 2D coordinates
// The shape must be convex, can be specified in clockwise or in counterclockwise direction
var shape2d=new CSG.Polygon2D([[0,0], [5,0], [3,5], [0,5]]);
// Do some transformations:
shape2d=shape2d.translate([-2, -2]);
shape2d=shape2d.rotate(20);
shape2d=shape2d.scale([0.2, 0.2]);
// And extrude. This creates a CSG solid:
var extruded=shape2d.extrude({
offset: [0.5, 0, 2], // direction for extrusion
twistangle: 180, // top surface is rotated 180 degrees
twiststeps: 100 // create 100 slices
});