@woosh/meep-engine/src/core/math/noise/noise_octaves.js

Pure JavaScript game engine. Fully featured and production ready.

export function noise_octaves(
    noise,
    noise_ctx,
    x, y, z,
    octaves,
    persistence = 0.5,
    lacunarity = 2
) {
    let total = 0;
    let frequency = 1;
    let amplitude = 1;

    let totalAmplitude = 0;  // Used for normalizing result to 0.0 - 1.0
    let i = 0;

    for (; i < octaves; i++) {

        const noise_value = noise.call(noise_ctx,
            x * frequency,
            y * frequency,
            z * frequency
        );

        total += noise_value * amplitude;

        totalAmplitude += amplitude;
        amplitude *= persistence;
        frequency *= lacunarity;
    }

    return total / totalAmplitude;
}