/**
 * Live-tunable glow parameters.
 *
 * Every number the halo + catch-light overlay used to hard-code lives here as
 * a mutable singleton so a tuning surface can drive it at runtime. Two classes:
 *
 *   • runtime — read every frame inside `updateGlow`. Changing one takes
 *     effect on the next frame with no DOM work.
 *   • markup — baked into the SVG (`buildSvgMarkup`) at inject time: stroke
 *     widths, blur radii, per-layer opacities, blob lengths. Changing one
 *     requires the SVG to be rebuilt, which `setGlowConfig` signals through
 *     `subscribeGlowConfig` so MetalFx can re-inject.
 *
 * `GLOW_DEFAULTS` are the values that shipped before this file existed, so
 * `resetGlowConfig()` is an exact restore.
 */
export interface GlowConfig {
    /** Overall halo group opacity multiplier. */
    haloOpMul: number;
    /** Catch-light group intensity multiplier (clamped to 1 after multiply). */
    extraIntensity: number;
    /** Glow opacity at a fully-lit perimeter point. */
    peakOp: number;
    /** Glow opacity at a dark perimeter point. */
    baseOp: number;
    /** Perpendicular inset of the halo from the ring, SVG units at 1×. */
    inset: number;
    /** Extra outward offset for the catch-light, SVG units at 1×. */
    extraOutward: number;
    /** Random wander amplitude along the perimeter, at the 140×40 reference. */
    wanderRange: number;
    /** Per-frame lerp toward the wander target. */
    wanderLerp: number;
    /** Per-frame lerp of opacity toward its luminance-driven target. */
    fadeRate: number;
    /** Luminance below which the glow sits at `baseOp`. */
    lumLo: number;
    /** Luminance above which the glow reaches `peakOp`. */
    lumHi: number;
    /** Minimum time at a hotspot before a brighter rival can steal it. */
    minDwellMs: number;
    /** Appear duration, ms. A relocation is a full fade-out at the old spot
     *  then a full fade-in at the new one — the glow never slides. */
    relocFadeMs: number;
    /** Disappear duration, ms. Slower than the appear so a hotspot lingers. */
    relocFadeOutMs: number;
    /** Point-mode (masked text/glyph) intensity multiplier. The mask discards
     *  most of the halo's blur, so what survives inside the strokes needs a
     *  boost to read at all. */
    pointGain: number;
    /** Half-length of the halo stroke path, at the reference pill. */
    haloHalfLen: number;
    /** Half-length of the catch-light stroke path, at the reference pill. */
    extraHalfLen: number;
    haloStrokeXl: number;
    haloStrokeLg: number;
    haloStrokeMd: number;
    haloStrokeSm: number;
    haloBlurXl: number;
    haloBlurLg: number;
    haloBlurMd: number;
    haloBlurSm: number;
    haloOpXl: number;
    haloOpLg: number;
    haloOpMd: number;
    haloOpSm: number;
    extraStrokeOuter: number;
    extraStrokeCore: number;
    extraBlurOuter: number;
    extraBlurCore: number;
    /** Radius of the radial mask that fades the catch-light's ends. */
    extraFadeR: number;
    extraOpOuter: number;
}
export declare const GLOW_MARKUP_KEYS: ReadonlySet<keyof GlowConfig>;
export declare const GLOW_DEFAULTS: Readonly<GlowConfig>;
/** Live values. Read directly by the glow engine; write via `setGlowConfig`. */
export declare const GLOW: GlowConfig;
type Listener = (markupChanged: boolean) => void;
/**
 * Merge a partial config. Notifies subscribers, flagging whether any markup
 * key changed so they can decide between "next frame picks it up" and
 * "rebuild the SVG".
 */
export declare function setGlowConfig(patch: Partial<GlowConfig>): void;
export declare function resetGlowConfig(): void;
export declare function subscribeGlowConfig(fn: Listener): () => void;
export {};