refactor: rivers generation

src/scripts/generation/pack/lakes.ts

@@ -0,0 +1,72 @@
+// @ts-nocheckd
+import * as d3 from "d3";
+
+import {rn} from "utils/numberUtils";
+import {getRealHeight} from "utils/unitUtils";
+
+export interface ILakeClimateData extends IPackFeatureLake {
+  flux: number;
+  temp: number;
+  evaporation: number;
+  outCell: number | undefined;
+  river?: number;
+  enteringFlux?: number;
+}
+
+export const getClimateData = function (
+  lakes: IPackFeatureLake[],
+  heights: number[],
+  drainableLakes: Dict<boolean>,
+  gridReference: IPack["cells"]["g"],
+  precipitation: IGrid["cells"]["prec"],
+  temperature: IGrid["cells"]["temp"]
+): ILakeClimateData[] {
+  const lakeData = lakes.map(lake => {
+    const {shoreline} = lake;
+
+    // default flux: sum of precipitation around lake
+    const flux = shoreline.reduce((acc, cellId) => acc + precipitation[gridReference[cellId]], 0);
+
+    // temperature and evaporation to detect closed lakes
+    const temp = rn(d3.mean(shoreline.map(cellId => temperature[gridReference[cellId]]))!, 1);
+
+    const height = getRealHeight(lake.height); // height in meters
+    const cellEvaporation = ((700 * (temp + 0.006 * height)) / 50 + 75) / (80 - temp); // based on Penman formula, [1-11]
+    const evaporation = rn(cellEvaporation * lake.cells);
+
+    const outCell =
+      flux > evaporation && drainableLakes[lake.i]
+        ? shoreline[d3.scan(shoreline, (a, b) => heights[a] - heights[b])!]
+        : undefined;
+
+    return {...lake, flux, temp, evaporation, outCell};
+  });
+
+  return lakeData;
+};
+
+export const mergeLakeData = function (
+  features: TPackFeatures,
+  lakeData: ILakeClimateData[],
+  rivers: Pick<IRiver, "i">[]
+) {
+  const updatedFeatures = features.map(feature => {
+    if (!feature) return 0;
+    if (feature.type !== "lake") return feature;
+
+    const lake = lakeData.find(lake => lake.i === feature.i);
+    if (!lake) return feature;
+
+    const {flux, temp, evaporation} = lake;
+    const inlets = lake.inlets?.filter(inlet => rivers.find(river => river.i === inlet));
+    const outlet = rivers.find(river => river.i === lake.outlet)?.i;
+
+    const lakeFeature: IPackFeatureLake = {...feature, flux, temp, evaporation, inlets, outlet};
+    if (!inlets || !inlets.length) delete lakeFeature.inlets;
+    if (!outlet) delete lakeFeature.outlet;
+
+    return lakeFeature;
+  });
+
+  return updatedFeatures as TPackFeatures;
+};