refactor(generation): rankCells

src/scripts/generation/pack/pack.ts

@@ -1,14 +1,11 @@
 import * as d3 from "d3";
 
-import {markupPackFeatures} from "scripts/generation/markup";
-// @ts-expect-error js module
-import {drawScaleBar} from "modules/measurers";
-// @ts-expect-error js module
-import {addZones} from "modules/zones";
+import {UINT16_MAX} from "config/constants";
 import {DISTANCE_FIELD, MIN_LAND_HEIGHT} from "config/generation";
 import {TIME} from "config/logging";
-import {UINT16_MAX} from "config/constants";
 import {calculateVoronoi} from "scripts/generation/graph";
+import {markupPackFeatures} from "scripts/generation/markup";
+import {rankCells} from "scripts/generation/pack/rankCells";
 import {createTypedArray} from "utils/arrayUtils";
 import {pick} from "utils/functionUtils";
 import {rn} from "utils/numberUtils";
@@ -51,8 +48,18 @@ export function createPack(grid: IGrid): IPack {
     gridReference: cells.g
   });
 
-  // const rankCellsData = pick(newPack.cells, "i", "f", "fl", "conf", "r", "h", "area", "biome", "haven", "harbor");
-  // rankCells(newPack.features!, rankCellsData);
+  const {suitability, population} = rankCells(mergedFeatures, {
+    t: distanceField,
+    f: featureIds,
+    fl: riverIds,
+    conf,
+    r: riverIds,
+    h: heights,
+    area: cells.area,
+    biome,
+    haven,
+    harbor
+  });
 
   // Cultures.generate();
   // Cultures.expand();
@@ -90,10 +97,13 @@ export function createPack(grid: IGrid): IPack {
       fl: flux,
       r: riverIds,
       conf,
-      biome
+      biome,
+      s: suitability,
+      pop: population
+      // state, culture, religion, province, burg
     },
     features: mergedFeatures,
-    rivers: rawRivers
+    rivers: rawRivers // "name" | "basin" | "type"
   };
 
   return pack;

src/scripts/generation/pack/rankCells.ts

@@ -0,0 +1,90 @@
+import * as d3 from "d3";
+
+import {DISTANCE_FIELD, MIN_LAND_HEIGHT} from "config/generation";
+import {TIME} from "config/logging";
+import {normalize} from "utils/numberUtils";
+
+const FLUX_MAX_BONUS = 250;
+const SUITABILITY_FACTOR = 5;
+
+// assess cells suitability for population and rank cells for culture centers and burgs placement
+export function rankCells(
+  features: TPackFeatures,
+  cells: Pick<IPack["cells"], "t" | "f" | "fl" | "conf" | "r" | "h" | "area" | "biome" | "haven" | "harbor">
+) {
+  TIME && console.time("rankCells");
+
+  const cellsNumber = cells.h.length;
+  const suitability = new Int16Array(cellsNumber); // cell suitability array
+  const population = new Float32Array(cellsNumber); // cell population array
+
+  const meanFlux = d3.median(cells.fl.filter(f => f)) || 0;
+  const maxFlux = (d3.max(cells.fl) || 0) + (d3.max(cells.conf) || 0); // to normalize flux
+  const meanArea = d3.mean(cells.area) || 0; // to adjust population by cell area
+
+  const isWater = (cellId: number) => cells.h[cellId] < MIN_LAND_HEIGHT;
+  const isCoastal = (i: number) => cells.t[i] === DISTANCE_FIELD.LAND_COAST;
+
+  for (let cellId = 0; cellId < cellsNumber; cellId++) {
+    if (isWater(cellId)) continue; // no population in water
+
+    const habitabilityBonus = getHabitabilityBonus(cellId); // [0, 100]
+    if (!habitabilityBonus) continue; // uninhabitable biomes are excluded
+
+    const riverBonus = getFluxBonus(cellId); // [0, 250]
+    const elevationBonus = getElevationBonus(cellId); // [-10, 6]
+    const coastBonus = getCoastBonus(cellId); // [-30, 30]
+    const estuaryBonus = getEstuaryBonus(cellId); // [0, 15]
+
+    const bonuses = [habitabilityBonus, riverBonus, elevationBonus, coastBonus, estuaryBonus];
+    const total = d3.sum(bonuses) / SUITABILITY_FACTOR; // [-30, 311]
+    suitability[cellId] = total;
+
+    // cell rural population is suitability adjusted by cell area
+    population[cellId] = total > 0 ? total * (cells.area[cellId] / meanArea) : 0;
+  }
+
+  TIME && console.timeEnd("rankCells");
+
+  return {suitability, population};
+
+  function getHabitabilityBonus(cellId: number) {
+    return biomesData.habitability[cells.biome[cellId]];
+  }
+
+  function getFluxBonus(cellId: number) {
+    if (!cells.fl[cellId]) return 0;
+    return normalize(cells.fl[cellId] + cells.conf[cellId], meanFlux, maxFlux) * FLUX_MAX_BONUS;
+  }
+
+  function getElevationBonus(cellId: number) {
+    return (50 - cells.h[cellId]) / 5;
+  }
+
+  function getCoastBonus(cellId: number) {
+    if (!isCoastal(cellId)) return 0;
+
+    const havenCell = cells.haven[cellId];
+    const feature = features[cells.f[havenCell]];
+    if (!feature) return 0;
+
+    const {group} = feature;
+
+    // lake coast
+    if (group === "freshwater") return 30;
+    if (group == "salt") return 10;
+    if (group == "frozen") return 1;
+    if (group == "dry") return 1;
+    if (group == "sinkhole") return 3;
+    if (group == "lava") return -30;
+
+    // ocean coast
+    if (cells.harbor[cellId] === 1) return 25; // safe harbor
+    return 5; // unsafe harbor
+  }
+
+  // estuary bonus is [0, 15]
+  function getEstuaryBonus(cellId: number) {
+    return cells.r[cellId] && isCoastal(cellId) ? 15 : 0;
+  }
+}

src/scripts/generation/pack/rivers.ts

@@ -47,7 +47,7 @@ export function generateRivers(
 
   TIME && console.timeEnd("generateRivers");
 
-  return {heights, flux, riverIds, conf, rivers, mergedFeatures};
+  return {heights: new Uint8Array(heights), flux, riverIds, conf, rivers, mergedFeatures};
 
   function drainWater() {
     const MIN_FLUX_TO_FORM_RIVER = 30;