Sigma.js - Export image

This package provides various functions to capture snapshots of a sigma.js instance as images, allowing easy export of your graph visualizations in different formats.

Available Options

The following options can be used to customize the image export:

• layers (null | string[], default: null): Specify the graph layers to render (from sigma.getCanvases()). If null, all layers are rendered.
• width (null | number, default: null): Set the width of the output image. If null, the canvas will use the sigma container's width.
• height (null | number, default: null): Set the height of the output image. If null, the canvas will use the sigma container's height.
• fileName (string, default: "graph"): The name of the file to download.
• format ("png" | "jpeg", default: "png"): The image format, either PNG or JPEG.
• sigmaSettings (Partial<Settings>, default: {}): Custom settings for the sigma instance used during rendering.
• cameraState (null | CameraState, default: null): The camera state to use for the rendering. If null, the current camera state is used.
• backgroundColor (string, default: "transparent"): The background color of the image.
• withTempRenderer (null | ((tmpRenderer: Sigma) => void) | ((tmpRenderer: Sigma) => Promise<void>), default: null): A callback function for custom operations using the temporary sigma renderer before rendering the image.

Available Functions

drawOnCanvas

This function creates a new temporary sigma instance, renders it with the given options, and draws its layers (or the selected layers) on a new HTML canvas element. It then returns it as a Promise<HTMLCanvasElement>. This function is the core function, used by all other ones.

toBlob

This function returns a Promise<Blob> that contains the image data, which can be further processed or stored, useful for integration with file storage services.

toFile

This function returns a Promise<File> that contains the image data as a file, ideal for direct file manipulation or uploads.

downloadAsImage

This function downloads a snapshot of the sigma instance as an image file.

downloadAsPNG / downloadAsJPEG

These functions are simple sugar around downloadAsImage, without having to specify the "format" option.

Please check the related Storybook for more advanced examples.