/** Speed of sound in air at 20 °C, metres per second — the default for {@link dopplerRate}. */
export declare const SPEED_OF_SOUND = 343;
type Vec3Tuple = readonly [number, number, number];
/** Options for {@link dopplerRate}. */
export interface DopplerOptions {
    /** Scales both velocities; 1 is physical, 0 disables the shift. Default 1. */
    factor?: number;
    /** World units per second sound travels. Default {@link SPEED_OF_SOUND}. */
    speedOfSound?: number;
    /** Clamp window for the returned multiplier. Default `[0.5, 2]`. */
    range?: readonly [number, number];
}
/**
 * Doppler pitch multiplier for an emitter heard by a listener: `(c + vListener) / (c - vEmitter)`,
 * where each speed is the component along the line between them, positive when closing. Multiply a
 * loop's playback rate by it. Pure and allocation-free.
 *
 * @capability doppler-pitch pitch a moving sound up as it approaches and down as it passes, from listener and emitter velocity
 */
export declare function dopplerRate(listenerPosition: Vec3Tuple, listenerVelocity: Vec3Tuple, emitterPosition: Vec3Tuple, emitterVelocity: Vec3Tuple, options?: DopplerOptions): number;
export {};