Added simple graph data structure

src/display/graph.ts

+import { LineMaterial } from "three-fatline";
+
+export interface GraphNode extends NodeData {
+    x: number;
+    y: number;
+    z: number;
+    vx: number;
+    vy: number;
+    vz: number;
+    fx: number;
+    fy: number;
+    fz: number;
+    color: string;
+}
+
+export interface GraphLink extends LinkData {
+    material?: LineMaterial;
+}
+
+export interface LinkData {
+    source: NodeData;
+    target: NodeData;
+    type?: string;
+}
+
+export interface NodeData {
+    id: string;
+    name: string;
+    description?: string;
+    type?: string;
+    video?: string;
+    neighbors: NodeData[];
+    links: LinkData[];
+}
+
+export interface Coordinate {
+    x: number;
+    y: number;
+    z: number;
+}
+
+export class Graph {
+    public nodes: NodeData[];
+    public links: LinkData[];
+    private idToNode: Map<string, NodeData>;
+
+    constructor(nodes: NodeData[], links: LinkData[]) {
+        this.nodes = nodes;
+        this.links = links;
+
+        this.idToNode = new Map<string, NodeData>();
+        nodes.forEach((node) => {
+            this.idToNode.set(node.id, node);
+        });
+        this.updateNodeData();
+    }
+
+    resetNodeData() {
+        for (const node of this.nodes) {
+            node.neighbors = [];
+            node.links = [];
+        }
+    }
+
+    /**
+     * Updates the graph data structure to contain additional values.
+     * Creates a 'neighbors' and 'links' array for each node object.
+     */
+    updateNodeData() {
+        this.resetNodeData();
+
+        this.links.forEach((link) => {
+            const a = link.source;
+            const b = link.target;
+            a.neighbors.push(b);
+            b.neighbors.push(a);
+            a.links.push(link);
+            b.links.push(link);
+        });
+    }
+
+    node(id: string): NodeData {
+        return this.idToNode.get(id);
+    }
+
+    /**
+     * Returns an array containing the different edge types of the graph.
+     * @returns {*[]}
+     */
+    getLinkClasses(): string[] {
+        const linkClasses: string[] = [];
+
+        this.links.forEach((link) => linkClasses.push(link.type));
+        return [...new Set(linkClasses)].map((c) => String(c));
+    }
+
+    getNodeClasses(): string[] {
+        const nodeClasses: string[] = [];
+        this.nodes.forEach((node) => nodeClasses.push(node.type));
+        return [...new Set(nodeClasses)].map((c) => String(c));
+    }
+
+    view(
+        nodeTypes: Map<string, boolean>,
+        linkTypes: Map<string, boolean>
+    ): Graph {
+        return new Graph(
+            this.nodes.filter((l) => nodeTypes.get(l.type)),
+            this.links.filter((l) => linkTypes.get(l.type))
+        );
+    }
+}