Fixed config seed

feather/server/src/main.rs

@@ -64,7 +64,7 @@ fn init_world_source(game: &mut Game, config: &Config) {
     // world otherwise. This is a placeholder:
     // we don't have proper world generation yet.
 
-    let seed = 42; // FIXME: load from the level file
+    let seed = worldgen::seed_from_string(&config.world.seed);
 
     let generator: Arc<dyn WorldGenerator> = match &config.world.generator[..] {
         "flat" => Arc::new(SuperflatWorldGenerator::new(

feather/worldgen/src/lib.rs

@@ -364,6 +364,18 @@ impl BiomeGenerator for StaticBiomeGenerator {
     }
 }
 
+pub fn seed_from_string(s: &str) -> u64 {
+    s.parse().unwrap_or_else(|_| {
+        if s.is_empty() {
+            rand::random()
+        } else {
+            s.chars()
+                .fold(0u32, |val, ch| val.wrapping_mul(31).wrapping_add(ch as u32))
+                as u64
+        }
+    })
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -468,4 +480,10 @@ mod tests {
         assert_eq!(biomes.get_at_block(-1, 0, -1), Biome::Plains);
         assert_eq!(biomes.get_at_block(-1, 0, 0), Biome::BirchForest);
     }
+
+    #[test]
+    fn test_seed_from_config() {
+        assert_eq!(seed_from_string("42"), 42);
+        assert_eq!(seed_from_string("Hello"), 69609650);
+    }
 }