import { type SkImage } from "@shopify/react-native-skia";
/** A rasterized white-circle sprite + its geometry. */
export interface ParticleSprite {
    image: SkImage | null;
    /** Side length of the square sprite box (px). */
    size: number;
    /** Radius of the white circle inside the box (px). */
    radius: number;
}
/**
 * Rasterize ONE anti-aliased **white** filled circle into a square sprite, once
 * (NOT per frame). Drawing it white lets each particle's per-sprite color
 * modulate (multiply) the texture to its own tint + alpha via `drawAtlas`.
 *
 * Mirrors the PictureRecorder pattern in `markerAtlas.ts`.
 */
export declare function buildParticleSprite(): ParticleSprite;
/** One particle ready to blit: world position + per-sprite scale/alpha/color. */
export interface ParticleInstance {
    x: number;
    y: number;
    scale: number;
    alpha: number;
    colorIndex: number;
}
/**
 * Pure, worklet-safe projection of the packed particle ring buffer into render
 * instances. No Skia — plain numbers only — so it's directly unit-testable.
 *
 * Preserves the exact size/opacity formulas the old per-slot `<Circle>` used:
 *   life  = max(0, 1 - (now - t0) / burstDur)   (skip if dt = now - t0 < 0)
 *   r     = size * (0.5 + life * 0.5),  size = buf[base+6] || 1
 *   scale = r / spriteRadius
 *   alpha = life * particleOpacity
 * Inactive (active <= 0.5), pre-spawn (dt < 0) and fully-faded (life <= 0)
 * slots are skipped. Pass distinct `out` and `pool` arrays to retain inactive
 * instance objects for later bursts while returning only the active prefix.
 */
export declare function buildParticleInstances(buf: Float64Array, slots: number, now: number, burstDur: number, particleOpacity: number, spriteRadius: number, out?: ParticleInstance[], pool?: ParticleInstance[]): ParticleInstance[];
//# sourceMappingURL=particleAtlas.d.ts.map