A threejs based CAD viewer

Overview

The CAD viewer can visualize low level threejs objects (tessellated objects)

Live Examples

Shape and Shapes

A Shape contains the attributes

vertices (the BufferGeometry attribute position)
triangles (the triangle index of the BufferGeometry)
normals (the BufferGeometry attribute normal)

as described e.g. in BufferGeometry or Three.js Custom BufferGeometry

plus additionally the attribute

edges

to define which edges of the mesh should be shown.

The 4 attributes (vertices, triangles, normals, edges) define an object called Shape, see Class Shape

Multiple Shapes can be arranged as an hierarchical tree. This tree is modelled as Shapes object, see Class Shapes

The ids on each level define a path to each node and leaf of tree, e.g. /level1/level2_obj1/level3_object7 and so on.

States

For each leaf of the tree a 2 dim tuple needs to be provided to define whether shape and edges should be shown

0 = shape/edges hidden
1 = shape/edges shown
3 = shape/edges does not exist

The value 2 is reserved for nodes and shows a mixed state, i.d. some of the children are show, some not.

For the States object, see Class States

Skeleton:

<html>
  <head>
    <link rel="stylesheet" href="./dist/three-cad-viewer.esm.css" />
    <script type="module">
      import { Viewer, Display, Timer } from "./dist/three-cad-viewer.esm.js";

      function nc(change) {
        console.log("NOTIFY:", JSON.stringify(change, null, 2));
      }

      const options = {
        theme: "light",
        ortho: true,
        control: "trackball", // "orbit",
        normalLen: 0,
        cadWidth: 800,
        height: 600,
        treeWidth: 240,
        ticks: 10,
        normalLen: 0,
        ambientIntensity: 0.9,
        directIntensity: 0.12,
        transparent: false,
        blackEdges: false,
        axes: true,
        grid: [false, false, false],
        timeit: false,
        rotateSpeed: 1,
      };

      const shapes = {}; // a Shapes object, see example or API docs
      const states = {}; // a States object, see example or API docs

      // 1) get the container
      const container = document.getElementById("cad_view");

      // 2) Create the CAD display in this container
      const display = new Display(container, options);

      // 3) Create the CAD viewer
      const viewer = new Viewer(display, true, options, nc);

      // 4) Render the shapes and provide states for the navigation tree in this viewer
      viewer.render(shapes, states);
    </script>
  </head>

  <body>
    <div id="cad_view"></div>
  </body>
</html>

Examples

To understand the data format, a look at the simple 1 unit sized box might be helpful:

1 unit sized box source code

APIs of Viewer, Display, Camera and Controls

API docs

Back to Github repo

Development

Run a web server in watch mode

yarn run start

For the deployment, see Release.md

Changes

v1.7.0

Changed Z orientation to follow standard CAD programs. The old behaviour can be still used by using uo="L" (legacy)

v1.6.4

add support for color alpha channel

v1.6.3

Introduce a new parameter "up" that determines whther camera up is Y (up="Y") or Z (up="Z")

v1.6.2

Fixed bounding box max_dist_from_center algorithm

v1.6.1

Increase minimum width to 970
Handle more button in glassMode function
Allow resizing after view is created

v1.6.0

Disable jupyter cell select on shift mousedown in cad tree
Remove bounding box for isolate mode and improve click states
Center isolated objects around bounding box center
Extend help for picking/hiding/isolating
highlight tree node when element picked
A new bounding box algorithm (AABB)

v1.5.9

fixed a regression from v1.5.8 around initial zoom value handling)

v1.5.8

fixed glass and tools paramewter handling
fixed initial zoom for wide cad views with low height

v1.5.7

fixed ids of checkboxes to be unique across the document

cristhiand3/three-cad-viewer