three-tube-wireframe

Build a wireframe geometry made of cylinders from the input THREE.Geometry. This is expensive and leads to a lot of vertices, so its best suited for simple geometries.

Motivations:

• Thicker wireframes than what gl.LINES supports
• Volumetric wireframe meshes made up of cylindrical tubes
• Different face organization such as quads or cross-hatching lines

There are some limitations to this approach, including joins (no attempt is made to join the line segments) and occasional issues with different face organizations (this library makes assumptions about the layout of the incoming THREE.Geometry, which may not always be accurate).

Example:

// Create a base geometry
const geometry = new THREE.TorusGeometry(1, 0.25, 8, 16);

// Now build a wireframe geometry out of it
const wireGeometry = createTubeWireframe(geometry, {
  thickness: 0.03, // thickness in world units of tubes
  radiusSegments: 6, // number of segments around the tubes
  mode: 'quad' // face layout, use quads instead of triangles
});

// And finally add it to the scene
const mesh = new THREE.Mesh(
  wireGeometry,
  new THREE.MeshPhysicalMaterial({
    color: 'white',
    roughness: 0.75,
    flatShading: true
  })
);
scene.add(mesh);

Install

Use npm to install.

npm install three-tube-wireframe --save

It assumes three module is already installed and able to be required by your build tool.

Usage

wireGeo = createTubeWireframe(baseGeo, opt = {})

Builds a new THREE.Geometry from baseGeo using the given options:

• thickness (default 1) thickness/radius of each individual tube

• radiusSegments (default 4) number of radial segments around each individual tube

• lengthSegments (default 1) number of segments along each individual tube

• openEnded (default false) whether tubes should be open or closed ended

• matrix (default identity) a THREE.Matrix4 to apply to all segments as the geometry is being built

• filter (default pass-through) a function that accepts (index, mode) parameters and returns true (accept face) or false (discard face). If the mode is anything except 'triangle', the index will be incremented in steps of 2.

• buffer (defualt false) if true, returns a THREE.BufferGeometry with an additional basePosition attribute, which provides the positions of the original input baseGeo before wireframe expansion

• mode (string, default 'triangle') a face layout mode, can be one of the following. Some geometries (such as THREE.IcosahedronGeometry) may produce unusual results with non-triangle modes.

  • 'triangle' build triangles
  • 'quad' attempt to organize into quads
  • 'diagonal0' or 'diagonal1' diagonal lines in different directions
  • 'cross-hatch' a mix of diagonal lines
  • 'horizontal' or 'vertical' straight lines
  • 'diagonal0-horizontal' or 'diagonal1-horizontal' a mix of diagonal and horizontal lines
  • 'diagonal0-vertical' or 'diagonal1-vertical' a mix of diagonal and vertical lines

modes = createTubeWireframe.modes

A list of all the mode names ('triangle', 'quad', etc) that can be passed into the options.

License

MIT, see LICENSE.md for details.