Program and Rendering Functions

Program functions

Package-level functions create, compose, or render programs. They are not chainable actions and do not modify the action trace.

Exact TypeScript signatures

These blocks are generated from the declaration file owned by each package entry.

`ggaction`

export function chart(): ChartProgram;
export function hconcat(options: CompositionOptions): ChartProgram;
export function vconcat(options: CompositionOptions): ChartProgram;
export function render(
  program: Pick<ChartProgram, "graphicSpec">,
  context: CanvasRenderingContext2D,
  options?: { pixelRatio?: number }
): void;

`ggaction/basic`

export function chart(): BasicChartProgram;
export function render(
  program: Pick<BasicChartProgram, "graphicSpec">,
  context: CanvasRenderingContext2D,
  options?: { pixelRatio?: number }
): void;

`ggaction/svg`

export interface SVGRenderOptions {
  readonly title?: string;
  readonly description?: string;
  readonly resourceNamespace?: string;
}

export function renderToSVG(
  program: Pick<ChartProgram, "graphicSpec">,
  options?: SVGRenderOptions
): string;

`ggaction/png`

export interface PNGRenderResult {
  readonly output: string;
  readonly width: number;
  readonly height: number;
  readonly pixelRatio: number;
  readonly bytes: number;
}

export function renderToPNG(
  program: Pick<ChartProgram, "graphicSpec">,
  options: { output: string; pixelRatio?: number }
): Promise<PNGRenderResult>;

`ggaction/pdf`

export interface PDFMetadata {
  readonly title?: string;
  readonly author?: string;
  readonly subject?: string;
  readonly keywords?: readonly string[];
}

export interface PDFRenderOptions {
  readonly output: string;
  readonly metadata?: PDFMetadata;
}

export interface PDFRenderResult {
  readonly output: string;
  readonly width: number;
  readonly height: number;
  readonly pages: 1;
  readonly bytes: number;
}

export function renderToPDF(
  program: Pick<ChartProgram, "graphicSpec">,
  options: PDFRenderOptions
): Promise<PDFRenderResult>;

Rendering functions

Use Program composition for sizing, nesting, layout editing, and stable child replacement. Use Rendering for complete Browser Canvas, SVG, Node PNG, and vector PDF examples.

Internal trace operations

High-level actions call additional wrapped operations for data, scale, mark, guide, title, and layout materialization. Names such as materializeDensityData, materializeWindowData, materializeBin2DData, rematerializeScale, rematerializePointMark, createCategoricalLegend, createSizeLegend, rematerializeSizeLegend, createLegendSymbols, and createTitleText may appear in program.trace. They are deliberately absent from the public TypeScript declaration and this direct-call reference. Their arguments and decomposition may change as implementation details while the parent public action remains stable.

Use the Actions and trace trees page to inspect these nodes. Extension actions should compose the declared extension and advanced actions instead of calling an undeclared runtime method.