/**
 * First (simple) renderer: Canvas 2D.
 * Composes draw layers over a dark background; the base layer draws
 * field arrows (⊙ purple toward the viewer / ⊗ gold cross away) at every
 * readable-grid intersection at viewer scale.
 * A WebGPU renderer will replace this behind the same interface.
 */
import { type ViewTransform } from "../core/grid.js";
import { type RgRule } from "../core/rule.js";
import { type RgTheme } from "../core/theme.js";
export type DrawLayer = (ctx: CanvasRenderingContext2D, t: ViewTransform, size: {
    width: number;
    height: number;
}) => void;
export interface GridRenderer {
    render(t: ViewTransform): void;
    resize(): void;
}
export declare function createCanvas2DRenderer(canvas: HTMLCanvasElement, layers: DrawLayer[], opts?: {
    /**
     * background fill; false = transparent (compositing over an underlay);
     * a getter re-reads per frame — live theme swaps need no renderer rebuild
     */
    background?: string | false | (() => string | false);
    /** cap the backing-store scale (raster cost grows with dpr²) */
    maxDpr?: number;
}): GridRenderer;
/** world-space attractors that bend the grid field (e.g. off-screen nodes) */
export type FieldSource = {
    x: number;
    y: number;
};
/**
 * Base layer: every readable-grid point is a unit 3-D FIELD ARROW.
 * By default the arrows point at the viewer and render as purple dots (⊙,
 * the arrowhead seen head-on). When `zDir` reports the field pointing into
 * the screen (e.g. while zooming out), they flip to gold crosses (⊗, the
 * fletching seen from behind) — the physics notation for out-of/into the
 * page. With a `field` provider, major arrows tilt sideways under the
 * inverse-square pull of the sources (off-screen nodes feel like gravity —
 * the RG flow made visible) and grow a tail. One path per level: perf flat.
 */
export declare function createGridDotsLayer(rule?: RgRule, field?: () => FieldSource[], 
/** z of the field arrows: +1 = at the viewer (⊙), -1 = into the screen (⊗) */
zDir?: () => number, 
/**
 * global lateral field direction (viewport 3-D rotation): the grid DOTS
 * keep their screen positions, but every arrow leans this way — rotate
 * the box 180° and the whole field flips to ⊗ (pointing into the screen)
 */
fieldTilt?: () => readonly [number, number], 
/** live theme object (mutated by viewer.setTheme); arrow colors read per frame */
theme?: RgTheme): DrawLayer;
/** Default grid-dots layer using DEFAULT_RULE. */
export declare const gridDotsLayer: DrawLayer;
//# sourceMappingURL=canvas2d.d.ts.map