Better world generation

tests/worldgen_test.ts

@@ -0,0 +1,40 @@
+import { assert, assertEquals } from "@std/assert";
+import { CHUNK_AREA, CHUNK_HEIGHT, SEA_LEVEL } from "$/common/constants.ts";
+import { generate_raw_chunk } from "$/common/generation.ts";
+import { test_game } from "./helpers.ts";
+
+Deno.test("the overworld generates the same way every time, with water only below sea level", async () => {
+	const { game } = await test_game("mods");
+	const ids = game.world.block_ids;
+	const water = ids["bworld:water"];
+
+	for (let cx = -4; cx < 4; cx++) {
+		for (let cz = -4; cz < 4; cz++) {
+			const { blocks } = generate_raw_chunk(cx, cz, "worldgen-test", ids);
+			assertEquals(blocks, generate_raw_chunk(cx, cz, "worldgen-test", ids).blocks, "same chunk, same blocks");
+
+			for (let i = 0; i < CHUNK_AREA; i++) {
+				assert(blocks[i] !== 0, "the bottom of the world is solid");
+				assertEquals(blocks[(CHUNK_HEIGHT - 1) * CHUNK_AREA + i], 0, "nothing reaches the top of the world");
+			}
+			blocks.forEach((block, i) => {
+				if (block === water) {
+					assert(Math.floor(i / CHUNK_AREA) < SEA_LEVEL, "water above sea level");
+				}
+			});
+		}
+	}
+});
+
+Deno.test("new players spawn on dry land, all in the same place", async () => {
+	const { game, join } = await test_game("mods");
+	const joined = join(1, "alice");
+	const { x, y, z } = joined.spawn;
+	const ground = game.world.get_block_id(Math.floor(x), y - 1, Math.floor(z));
+	assert(ground !== "bworld:air" && ground !== "bworld:water", `spawned on ${ground}`);
+	assertEquals(game.world.get_block_id(Math.floor(x), y, Math.floor(z)), "bworld:air");
+	assert(y > SEA_LEVEL, "above the sea");
+
+	// the same place for the next new player
+	assertEquals(join(2, "bob").spawn, joined.spawn);
+});