Refactor chunk generation

Author: CuddlyBunion341

src/server/terrain/util/generator.rs

@@ -2,24 +2,8 @@ use terrain_resources::{Generator, NoiseFunctionParams, TerrainGeneratorParams};
 
 use crate::prelude::*;
 
-impl Generator {
-    pub fn new(seed: u32) -> Generator {
-        Self::new_with_params(seed, TerrainGeneratorParams::default())
-    }
-
-    pub fn new_with_params(seed: u32, params: TerrainGeneratorParams) -> Generator {
-        Generator {
-            seed,
-            perlin: Perlin::new(seed),
-            params,
-        }
-    }
-
-    pub fn generate_chunk(&self, chunk: &mut Chunk) {
-        if chunk.position.y < 0.0 {
-            return;
-        }
-
+macro_rules! for_each_chunk_coordinate {
+    ($chunk:expr, $body:expr) => {
         for x in 0..CHUNK_SIZE + 2 {
             for y in 0..CHUNK_SIZE + 2 {
                 for z in 0..CHUNK_SIZE + 2 {
@@ -34,14 +18,40 @@ impl Generator {
                         continue;
                     }
 
-                    let chunk_origin = chunk.position * CHUNK_SIZE as f32;
+                    let chunk_origin = $chunk.position * CHUNK_SIZE as f32;
                     let local_position = Vec3::new(x as f32, y as f32, z as f32);
                     let block_position = chunk_origin + local_position;
-                    let block = self.generate_block(block_position);
-                    chunk.set_unpadded(x, y, z, block);
+
+                    $body(x, y, z, block_position);
                 }
             }
         }
+    };
+}
+
+
+impl Generator {
+    pub fn new(seed: u32) -> Generator {
+        Self::new_with_params(seed, TerrainGeneratorParams::default())
+    }
+
+    pub fn new_with_params(seed: u32, params: TerrainGeneratorParams) -> Generator {
+        Generator {
+            seed,
+            perlin: Perlin::new(seed),
+            params,
+        }
+    }
+
+    pub fn generate_chunk(&self, chunk: &mut Chunk) {
+        if chunk.position.y < 0.0 {
+            return;
+        }
+
+        for_each_chunk_coordinate!(chunk, |x, y, z, block_position| {
+            let block = self.generate_block(block_position);
+            chunk.set_unpadded(x, y, z, block);
+        });
     }
 
     fn generate_block(&self, position: Vec3) -> BlockId {