ReferenceSamplersFunction

cone()

Creates velocities in a direction, with some random spread.

function cone(
    angle: number,
    deviation: number,
    speed: Sampler<number>,
): SamplerFn<Vec3>;

Creates a sampler for velocities that point in a direction, with some deviation.

Angles are in degrees, measured counter-clockwise from +x in particle space, so 0 points right and 90 points up. The angle is chosen with spread(), so a burst fans out evenly across the cone. A deviation of 0 sends every particle in exactly the same direction.

Parameters

anglenumber: The direction of the cone’s center, in degrees.
deviationnumber: How far a particle’s direction may lie from angle, in degrees, in either direction.
speedSampler<number>: The speed, in px/s. Can itself be a sampler.

Returns

SamplerFn<Vec3>

Example

// Upwards, fanning out 30° to either side, with constant speed.
cone(90, 30, 400);

// Straight down, at varying speeds.
cone(-90, 0, range(60, 120));