refactor: Remove legacy ocean-layers.js and migrate functionality to ocean-layers.ts

src/modules/ocean-layers.ts

@@ -0,0 +1,121 @@
+import { line, curveBasisClosed } from 'd3';
+import type { Selection } from 'd3';
+import { clipPoly,P,rn,round } from '../utils';
+
+declare global {
+  interface Window {
+    OceanLayers: any;
+  }
+
+  var TIME: boolean;
+  var ERROR: boolean;
+  var grid: any;
+  var oceanLayers: Selection<SVGGElement, unknown, null, undefined>;
+}
+class OceanModule {
+  private cells: any;
+  private vertices: any;
+  private pointsN: any;
+  private used: any;
+  private lineGen = line().curve(curveBasisClosed);
+  private oceanLayers: Selection<SVGGElement, unknown, null, undefined>;
+
+
+  constructor(oceanLayers: Selection<SVGGElement, unknown, null, undefined>) {
+    this.oceanLayers = oceanLayers;
+  }
+
+  get grid(): any {
+    return grid;
+  }
+
+  randomizeOutline() {
+    const limits = [];
+    let odd = 0.2;
+    for (let l = -9; l < 0; l++) {
+      if (P(odd)) {
+        odd = 0.2;
+        limits.push(l);
+      } else {
+        odd *= 2;
+      }
+    }
+    return limits;
+  }
+
+  // connect vertices to chain
+  connectVertices(start: number, t: number) {
+    const chain = []; // vertices chain to form a path
+    for (let i = 0, current = start; i === 0 || (current !== start && i < 10000); i++) {
+      const prev = chain[chain.length - 1]; // previous vertex in chain
+      chain.push(current); // add current vertex to sequence
+      const c = this.vertices.c[current]; // cells adjacent to vertex
+      c.filter((c: number) => this.cells.t[c] === t).forEach((c: number) => (this.used[c] = 1));
+      const v = this.vertices.v[current]; // neighboring vertices
+      const c0 = !this.cells.t[c[0]] || this.cells.t[c[0]] === t - 1;
+      const c1 = !this.cells.t[c[1]] || this.cells.t[c[1]] === t - 1;
+      const c2 = !this.cells.t[c[2]] || this.cells.t[c[2]] === t - 1;
+      if (v[0] !== undefined && v[0] !== prev && c0 !== c1) current = v[0];
+      else if (v[1] !== undefined && v[1] !== prev && c1 !== c2) current = v[1];
+      else if (v[2] !== undefined && v[2] !== prev && c0 !== c2) current = v[2];
+      if (current === chain[chain.length - 1]) {
+        ERROR && console.error("Next vertex is not found");
+        break;
+      }
+    }
+    chain.push(chain[0]); // push first vertex as the last one
+    return chain;
+  }
+
+  // find eligible cell vertex to start path detection
+  findStart(i: number, t: number) {
+      if (this.cells.b[i]) return this.cells.v[i].find((v: number) => this.vertices.c[v].some((c: number) => c >= this.pointsN)); // map border cell
+      return this.cells.v[i][this.cells.c[i].findIndex((c: number)=> this.cells.t[c] < t || !this.cells.t[c])];
+    }
+
+  draw() {
+    const outline = this.oceanLayers.attr("layers");
+    if (outline === "none") return;
+    TIME && console.time("drawOceanLayers");
+    this.cells = grid.cells;
+    this.pointsN = grid.cells.i.length;
+    this.vertices = grid.vertices;
+    const limits = outline === "random" ? this.randomizeOutline() : outline.split(",").map((s: string) => +s);
+  
+    const chains: [number, any[]][] = [];
+    const opacity = rn(0.4 / limits.length, 2);
+    this.used = new Uint8Array(this.pointsN); // to detect already passed cells
+
+    for (const i of this.cells.i) {
+      const t = this.cells.t[i];
+      if (t > 0) continue;
+      if (this.used[i] || !limits.includes(t)) continue;
+      const start = this.findStart(i, t);
+      if (!start) continue;
+      this.used[i] = 1;
+      const chain = this.connectVertices(start, t); // vertices chain to form a path
+      if (chain.length < 4) continue;
+      const relax = 1 + t * -2; // select only n-th point
+      const relaxed = chain.filter((v, i) => !(i % relax) || this.vertices.c[v].some((c: number) => c >= this.pointsN));
+      if (relaxed.length < 4) continue;
+      
+      const points = clipPoly(
+        relaxed.map(v => this.vertices.p[v]),
+        undefined,
+        undefined,
+        1
+      );
+      chains.push([t, points]);
+    }
+
+    for (const t of limits) {
+      const layer = chains.filter((c: [number, any[]]) => c[0] === t);
+      let path = layer.map((c: [number, any[]]) => round(this.lineGen(c[1]) || "")).join("");
+      if (path) this.oceanLayers.append("path").attr("d", path).attr("fill", "#ecf2f9").attr("fill-opacity", opacity);
+    }
+
+    TIME && console.timeEnd("drawOceanLayers");
+  }
+}
+
+window.OceanLayers = () => new OceanModule(oceanLayers).draw();