vector-field

A data structure and lookup for 3D vector fields (flow fields).

See the example and its source.

Installation

npm install vector-field

Usage

import VectorField from "vector-field";

let time = 0;
const directionFn = ([x, y, z]) => {
  const n = myNoise4D(x, y, z, time);
  const theta = n;
  const phi = n;

  return [
    Math.sin(theta) * Math.cos(phi),
    Math.sin(theta) * Math.sin(phi),
    Math.cos(theta),
  ];
};
const vectorField = new VectorField(directionFn, [12, 6, 6], 1);

const frame = () => {
  time += 0.001;
  vectorField.update();
  requestAnimationFrame(frame);
};

requestAnimationFrame(() => {
  frame();
});

API

Classes

Typedefs

VectorField

A data structure and lookup for 3D vector fields (flow fields).

Kind: global class Properties

| Name | Type | | ----------- | -------------------------------------------------------------- | | directionFn | VectorFieldDirectionFn | | steps | vec3 | | bounds | vec3 | | halfBounds | vec3 | | field | Array.<VectorFieldCell> |

• VectorField
  • new VectorField(directionFn, [steps], [bounds])
  • .update()
  • .lookup(cell) ⇒ VectorFieldCell | undefined

new VectorField(directionFn, [steps], [bounds])

Creates an instance of VectorField.

| Param | Type | Default | Description | | ----------- | -------------------------------------------------------------- | --------------- | ------------------------------------------------------------------------------------------------------------------------------------------ | | directionFn | VectorFieldDirectionFn | | The custom function to compute the cell direction (often a noise function) | | [steps] | number | vec3 | 10 | The number of steps on each dimension (all positive integer). Use integer for identical dimensions. | | [bounds] | number | vec3 | 1 | The size of a containing box for the field. Is divided into steps for each dimension (all positive). Use integer for identical dimensions. |

vectorField.update()

Create/update the field according to the provided noise function.

Kind: instance method of VectorField

vectorField.lookup(cell) ⇒ VectorFieldCell | undefined

Find a VectorFieldCell at specified position. Useful to compute a particle's velocity for instance.

Kind: instance method of VectorField

| Param | Type | Description | | ----- | -------------------------- | ------------ | | cell | vec3 | [cx, cy, cz] |

vec3 : Array.<number>

Kind: global typedef

VectorFieldCell : object

Kind: global typedef Properties

| Name | Type | | --------- | -------------------------- | | position | vec3 | | direction | vec3 |

VectorFieldDirectionFn : function

The custom function to compute the cell direction (often a noise function)

Kind: global typedef

| Param | Type | | ------------ | -------------------------- | | position | vec3 | | stepPosition | vec3 |

License

MIT. See license file.