import { PERIM_SAMPLES } from '../perf-config';
export { PERIM_SAMPLES };
export interface GlowOptions {
    width: number;
    height: number;
    cornerRadius: number;
    kind: 'pill' | 'circle';
    /** Master multiplier for absolute SVG units (stroke widths, blur,
     *  fade-circle radius). 1 is the canonical 1× rendering. Set to 2 when
     *  the host element is rendered at a 2× layout (e.g. CSS zoom: 2) so
     *  the glow grows proportionally. */
    scale?: number;
    /**
     * Point mode (custom-mask instances). `samplePoints` are box-local CSS-px
     * positions inside the mask where luminance is sampled and the hotspot can
     * sit; `maskDataUrl` is the mask rendered white-on-transparent, used to clip
     * the glow to the glyphs instead of the ring band.
     */
    samplePoints?: Pt[];
    maskDataUrl?: string;
}
export interface Pt {
    x: number;
    y: number;
}
export interface PerimSample extends Pt {
    arc: number;
}
export declare function rrPerim(w: number, h: number, r: number): number;
export declare function shapePerim(w: number, h: number, r: number, kind: 'pill' | 'circle'): number;
export declare function sampleAtArc(s: number, w: number, h: number, r: number, inset: number, outward: number, kind: 'pill' | 'circle', out?: Pt): Pt;
/**
 * Inverse of `sampleAtArc` at inset 0: the arc-length position on the outline
 * nearest a box-local point. Points off the outline project onto it.
 */
export declare function arcAtPoint(x: number, y: number, w: number, h: number, r: number, kind: 'pill' | 'circle'): number;
export declare function buildStaticBlobPath(halfLen: number, segments: number): string;
export declare function tangentAngleAtArc(s: number, w: number, h: number, r: number, inset: number, kind: 'pill' | 'circle'): number;
export declare function smoothstep(a: number, b: number, x: number): number;
export declare function buildPerimTable(opts: GlowOptions): PerimSample[];
export declare function buildSvgMarkup(opts: GlowOptions, p: string): string;