gl-shape

[![NPM version][npm-image]][npm-url]
![experimental][experimental-image]
[![js-standard-style][standard-image]][standard-url]

Create 3d shapes for use with stack.gl.

This module provides a constructor that wraps gl-geometry and gl-mat4, making it simpler to create a geometry from a simplicial complex and update its transforms.

install

``
npm install gl-shape
`

example

Define data for your shape

`javascript
var data = {
complex: require('bunny'),
position: [0, 10, 20],
scale: [1, 2, 1]
}
`

Then create it

`javascript
var shape = require('gl-shape')(data)
`

You can bind its geometry to a shader

`javascript
shape.attributes.geometry.bind(shader)
`

Use its matrices to set uniforms

`javascript
shader.uniforms.model = shape.attributes.model
`

And update its position (which updates its underlying model matrix)

`javascript
shape.position([0, 10, 0])
`

See example.js for a complete example of a rendered 3d shape, and call npm start to run it.

usage

#### shape = require('gl-shape')(gl, data)

Create a shape by providing a gl context and shape data.

The following properties on data are required
- complex the simplicial complex, must have positions and faces, may also have uvs and normals. If normals are not provided, vertex normals will be computed using normals.

And the following are optional
- position an 3 vector with a position
- scale an 3 vector with a scale in each dimension or a scalar
- rotation an object with rotation angle theta and 3 vector axis
- model a 4x4 matrix for directly specifying the model matrix
- flatten a boolean flag that if true will convert indexed meshes to triangles for non-interpolated geometries

If position, scale, or rotation are specified they will be used to set the model matrix.

#### shape.attributes

All derived attributes are stored on shape.attributes, and include
- geometry the renderable geometry
- model the 4x4 model matrix
- modelNormal the normal vector for the model

#### shape.position(vector)

Update the position.

#### shape.scale(vector)

Update the scale along each dimension. Can also pass a single value.

#### shape.rotation(angle, axis)`

Update the rotation.

[npm-image]: https://img.shields.io/badge/npm-v1.0.0-lightgray.svg?style=flat-square
[npm-url]: https://npmjs.org/package/gl-shape
[standard-image]: https://img.shields.io/badge/code%20style-standard-lightgray.svg?style=flat-square
[standard-url]: https://github.com/feross/standard
[experimental-image]: https://img.shields.io/badge/stability-experimental-lightgray.svg?style=flat-square