import type { PlotLayout } from "../layout/plot-layout";
type GL = WebGL2RenderingContext | WebGLRenderingContext;
/**
 * Return CSS-pixel dimensions of the GL canvas.
 */
export declare function cssSize(gl: GL, dpr: number): {
    cssWidth: number;
    cssHeight: number;
};
/**
 * Clear the framebuffer + enable alpha blending. Call once per frame,
 * before any per-plot-rect {@link withScissor} invocations. Faceted
 * renderers call this once and then loop {@link withScissor} per cell
 * so the inter-facet clears don't wipe each other's pixels.
 */
export declare function clearAndSetupFrame(gl: GL): void;
/**
 * Scissor-constrain `draw` to `layout.plotRect`. Caller handles
 * projection / uniforms / VBO bindings inside `draw`; this helper only
 * manages the scissor enable/disable bracket.
 *
 * Unlike {@link renderInPlotFrame}, this does *not* clear the
 * framebuffer — so it's safe to call repeatedly per frame (one per
 * facet). Pair with {@link clearAndSetupFrame} at the start of each
 * frame.
 */
export declare function withScissor(gl: GL, layout: PlotLayout, dpr: number, draw: () => void): void;
/**
 * One-shot convenience: clear + setup blend + scissor + draw. Used by
 * single-plot callers (bar / heatmap / candlestick / scatter-without-
 * splits) that only draw into one plot rect per frame.
 *
 * Faceted callers must use {@link clearAndSetupFrame} +
 * {@link withScissor} instead; calling this helper in a per-facet loop
 * would clear the framebuffer on each invocation and wipe out every
 * previously-drawn facet.
 */
export declare function renderInPlotFrame(gl: GL, layout: PlotLayout, dpr: number, draw: () => void): void;
export {};