Add forest types

island/generators.ts

@@ -49,8 +49,32 @@ export const BIG_BEACH: LobeGeneratorConstructor = (
   };
 };
 
-/** form forested zone */
-export const FOREST_LOBE: LobeGeneratorConstructor =
+/** form forested zone wherever available */
+export const SCATTERED_FOREST: LobeGeneratorConstructor =
+  (islands: IslandGrid, basePos: number) => () => {
+    const islandTiles = islands.floodSearch(basePos, (tile) => tile > WATER);
+
+    // grow shore
+    const shoreTiles = islandTiles.filter((pos) => islands.data[pos] == WATER);
+    islands.dropWithin(shoreTiles);
+
+    // seed beach
+    const beachTiles = islandTiles.filter((pos) => islands.data[pos] == BEACH);
+    islands.dropWithin(beachTiles);
+    islands.dropWithin(beachTiles);
+
+    // expand forest
+    const forestLobe = islands.floodSearch(basePos, (tile) => tile > WATER);
+    const forestTiles = forestLobe.filter(
+      (pos) => islands.data[pos] == LIGHT_FOREST
+    );
+    islands.dropWithin(forestTiles);
+
+    return true;
+  };
+
+/** form forested zone that tries to grow as one mass */
+export const CONTIGUOUS_FOREST: LobeGeneratorConstructor =
   (islands: IslandGrid, basePos: number) => () => {
     const islandTiles = islands.floodSearch(basePos, (tile) => tile > WATER);
 
@@ -62,20 +86,48 @@ export const FOREST_LOBE: LobeGeneratorConstructor =
     const beachTiles = islandTiles.filter((pos) => islands.data[pos] == BEACH);
     islands.dropWithin(beachTiles);
 
-    // expand forest
+    // locate & expand central forest edge
     const forestLobe = islands.floodSearch(basePos, (tile) => tile > BEACH);
     const forestTiles = forestLobe.filter(
       (pos) => islands.data[pos] == LIGHT_FOREST
     );
     islands.dropWithin(forestTiles);
     islands.dropWithin(forestTiles);
-    islands.dropWithin(forestTiles);
 
     return true;
   };
 
+/** form forested zone that can raise additional peaks */
+export const HILLY_FOREST: LobeGeneratorConstructor =
+  (islands: IslandGrid, basePos: number) => () => {
+    const islandTiles = islands.floodSearch(basePos, (tile) => tile > WATER);
+
+    // grow shore
+    const shoreTiles = islandTiles.filter((pos) => islands.data[pos] == WATER);
+    islands.dropWithin(shoreTiles);
+
+    // seed beach
+    const beachTiles = islandTiles.filter((pos) => islands.data[pos] == BEACH);
+    islands.dropWithin(beachTiles);
+
+    // locate central forest
+    const centralForest = islands.floodSearch(basePos, (tile) => tile > BEACH);
+    islands.dropWithin(centralForest);
+
+    // expand edge
+    const edgeTiles = centralForest.filter(
+      (pos) => islands.data[pos] == LIGHT_FOREST
+    );
+    islands.dropWithin(edgeTiles);
+
+    const hillTiles = centralForest.filter(
+      (pos) => islands.data[pos] >= MOUNTAIN
+    );
+    return hillTiles.length > 0;
+  };
+
 /** form low-lying beach with eroded sections */
-export const ERODED_LOBE: LobeGeneratorConstructor =
+export const ERODED_BEACH: LobeGeneratorConstructor =
   (islands: IslandGrid, basePos: number) => () => {
     const islandTiles = islands.floodSearch(basePos, (tile) => tile > WATER);
 
@@ -97,11 +149,20 @@ export const NO_ISLAND: LobeGeneratorConstructor =
     return true;
   };
 
-export const BIG_ISLANDS = [BIG_MOUNTAIN, BIG_BEACH];
+export const BIG_ISLANDS = [BIG_MOUNTAIN, BIG_BEACH, HILLY_FOREST];
+export const ROCKY_ISLANDS = [BIG_MOUNTAIN, HILLY_FOREST];
+export const GREEN_ISLANDS = [
+  SCATTERED_FOREST,
+  CONTIGUOUS_FOREST,
+  HILLY_FOREST,
+];
+export const SMALL_ISLANDS = [SMALL_BEACH, SCATTERED_FOREST, ERODED_BEACH];
 export const ALL_ISLANDS = [
   BIG_MOUNTAIN,
   SMALL_BEACH,
   BIG_BEACH,
-  FOREST_LOBE,
-  ERODED_LOBE,
+  SCATTERED_FOREST,
+  CONTIGUOUS_FOREST,
+  HILLY_FOREST,
+  ERODED_BEACH,
 ];

island/grid.ts

@@ -3,8 +3,11 @@ import { BEACH, ICECAP } from "./data";
 import {
   ALL_ISLANDS,
   BIG_ISLANDS,
+  GREEN_ISLANDS,
   LobeGenerator,
   NO_ISLAND,
+  ROCKY_ISLANDS,
+  SMALL_ISLANDS,
 } from "./generators";
 
 export class IslandGrid {
@@ -21,16 +24,18 @@ export class IslandGrid {
 
     const islandBag = this.shuffle([
       this.choose(BIG_ISLANDS),
-      this.choose(BIG_ISLANDS),
-      this.choose(ALL_ISLANDS),
-      this.choose(ALL_ISLANDS),
-      this.choose(ALL_ISLANDS),
+      this.choose(ROCKY_ISLANDS),
+      this.choose(GREEN_ISLANDS),
+      this.choose(SMALL_ISLANDS),
+      this.choose(SMALL_ISLANDS),
+      this.choose(SMALL_ISLANDS),
       this.choose(ALL_ISLANDS),
       NO_ISLAND,
       NO_ISLAND,
       NO_ISLAND,
       NO_ISLAND,
       NO_ISLAND,
+      NO_ISLAND,
     ]);
 
     const islandCount = islandBag.length;