react-diagrams/demos/demo-zoom-to-fit/index.tsx

import {
	DiagramEngine,
	DiagramModel,
	DefaultNodeModel,
	LinkModel,
	DefaultPortModel,
	DiagramWidget
} from "storm-react-diagrams";
import * as React from "react";
import { DemoWorkspaceWidget } from "../.helpers/DemoWorkspaceWidget";

/**
 *
 * Simple stress test of the system plus zoom to fit function
 *
 * @Author Dylan Vorster
 */
export default () => {
	//1) setup the diagram engine
	var engine = new DiagramEngine();
	engine.installDefaults();

	//2) setup the diagram model
	var model = new DiagramModel();

	for (var i = 0; i < 8; i++) {
		for (var j = 0; j < 8; j++) {
			generateNodes(model, i * 200, j * 100);
		}
	}

	//5) load model into engine
	engine.setModel(model);

	//6) render the diagram!
	return (
		<DemoWorkspaceWidget
			buttons={<button onClick={() => engine.getCanvasWidget().zoomToFit()}>Zoom to fit</button>}
		>
			<DiagramWidget className="srd-demo-canvas" diagramEngine={engine} />
		</DemoWorkspaceWidget>
	);
};

function generateNodes(model: DiagramModel, offsetX: number, offsetY: number) {
	//3-A) create a default node
	var node1 = new DefaultNodeModel("Node 1", "rgb(0,192,255)");
	var port1 = node1.addOutPort("Out");
	node1.setPosition(100 + offsetX, 100 + offsetY);

	//3-B) create another default node
	var node2 = new DefaultNodeModel("Node 2", "rgb(192,255,0)");
	var port2 = node2.addInPort("In");
	node2.setPosition(200 + offsetX, 100 + offsetY);

	//3-C) link the 2 nodes together
	var link1 = port1.link(port2);

	//4) add the models to the root graph
	model.addAll(node1, node2, link1);
}