export type CSSFilter = {
    filter: string;
    html?: string;
};
export declare enum Effects {
    sepia = "sepia",
    grayscale = "grayscale",
    natural = "natural",
    warm = "warm",
    cold = "cold",
    temperature = "temperature",
    contrast = "contrast",
    shadows = "shadows",
    white = "white",
    black = "black",
    vibrance = "vibrance",
    saturation = "saturation"
}
export declare function shapeFilterToCSS(filter: Effects, intensity?: number): CSSFilter | null;
/**
 * Whether this element's CSS `blur()` may be clipped to its element box.
 *
 * CSS `blur()` spreads past the element and konva's does not, so an unclipped
 * chain paints ink the canvas never draws. Clipping is only safe where the
 * element's ink IS its box, and an exporter cannot measure ink the way konva's
 * `node.cache()` does — so the types above are the ones where that holds by
 * construction. `image`/`svg`/`video`/`gif` paint a source scaled INTO the box,
 * the family the canvas blurs through `applyFiltersToCanvas`, which bakes the
 * blur into the source bitmap. `figure` paints a path inside the box and
 * strokes it CLIPPED TO THAT PATH (`figure-to-svg.ts`), whatever the subType.
 *
 * Everything else is excluded because its ink genuinely leaves the box: a
 * `line` draws heads reaching twice the element height past it, `text` at
 * `lineHeight < 1` draws above and below, and `group`/`table` hold children of
 * unknown extent. Clipping those DELETES ink — a blurred line lost both arrow
 * heads outright.
 *
 * Only `blur()` needs this. The colour filters are per-pixel, and a
 * `drop-shadow` is SUPPOSED to leave the box, so it belongs outside the clip.
 */
export declare function shouldClipBlurToBox(element: {
    type?: string;
    blurEnabled?: boolean;
    blurRadius: number;
    width: number;
    height: number;
    cropWidth?: number;
    cropHeight?: number;
}): boolean;
/**
 * The on-page direction of an element's shadow, expressed in the element's
 * LOCAL space.
 *
 * Konva paints shadows in page space — canvas 2D shadow offsets ignore the
 * node's transform — so on the canvas a rotated element's shadow keeps its
 * on-page direction. CSS `drop-shadow`/`text-shadow` and the PDF placement
 * are painted in the element's local space and then rotated with it, so they
 * must counter-rotate the model offsets to land in the same page direction.
 */
export declare function localShadowOffset(element: {
    shadowOffsetX: number;
    shadowOffsetY: number;
    rotation?: number;
}): {
    x: number;
    y: number;
};
/**
 * A text element with a background box casts ONE shadow, from the box — the
 * same meaning an element shadow has on an image, svg or figure, and what a
 * filled text box does in Keynote, PowerPoint or a Figma frame. The glyphs
 * cast their own shadow only when there is no box.
 */
export declare function shadowCastByBackground(element: {
    type?: string;
    backgroundEnabled?: boolean;
}): boolean;
/**
 * The element's full CSS filter chain, mirroring the canvas renderer:
 * blur/brightness/sepia/grayscale, then the named effects (`element.filters`),
 * then the drop-shadow. `additionalHTML` carries the inline `<svg><filter>`
 * markup some named effects need (html-export injects it verbatim;
 * svg-export rewraps the `<svg>` root as `<g>` since svg can't nest).
 *
 * Shadow parity notes: `shadowBlur / 2` because CSS drop-shadow's blur radius
 * semantics differ from konva's (halving matches the canvas visually), and
 * `shadowOpacity` is folded into the shadow color — konva applies it as a
 * separate multiplier, CSS has no such knob.
 *
 * The chain comes back in two halves, because they belong on different nodes
 * once `blur()` is in play: `boxFilters` has to be clipped to the element box
 * or the blur paints outside it (`shouldClipBlurToBox`), while `spreadFilters`
 * — the drop-shadow — is supposed to leave the box. A caller with nothing to
 * clip concatenates them onto one node.
 */
export declare function getElementCssFilters(element: {
    blurEnabled?: boolean;
    blurRadius: number;
    brightnessEnabled?: boolean;
    brightness: number;
    sepiaEnabled?: boolean;
    grayscaleEnabled?: boolean;
    filters?: Record<string, {
        intensity: number;
    }>;
    shadowEnabled?: boolean;
    shadowOffsetX: number;
    shadowOffsetY: number;
    shadowBlur: number;
    shadowColor: string;
    shadowOpacity?: number;
    rotation?: number;
    type?: string;
    backgroundEnabled?: boolean;
    width: number;
    height: number;
    cropWidth?: number;
    cropHeight?: number;
}): {
    boxFilters: string[];
    spreadFilters: string[];
    /** The drop-shadow when the text background box casts it (see
     * `shadowCastByBackground`); `spreadFilters` is empty then. */
    backgroundFilters: string[];
    additionalHTML: string[];
};
export declare function getEffectiveBlurRadius(blurRadius: number, width: number, height: number): number;
export declare function getElementBlurRadius(element: {
    blurRadius: number;
    width: number;
    height: number;
    cropWidth?: number;
    cropHeight?: number;
}): number;