feat(server): generate a cylinder of chunks around a center point

crates/server/src/main.rs

@@ -10,10 +10,7 @@ pub mod world_server;
 
 use std::fs;
 
-use shared::{
-    generator::{VoxelGenerator, WorldGenConfig},
-    world::ChunkPos,
-};
+use shared::generator::{VoxelGenerator, WorldGenConfig};
 use tracing::{debug, info};
 
 fn main() {
@@ -47,10 +44,5 @@ fn main() {
 
     let mut world = world_server::ServerWorld::new(generator);
 
-    let spawn_chunk = world.get_chunk(ChunkPos::new(0, 0, 0));
-
-    tracing::info!(
-        "Spawn chunk generated. Block at (0,0,0) is {}",
-        spawn_chunk.get(0, 0, 0).0
-    );
+    world.load_around(0.0, 0.0, 0.0, 4);
 }

crates/server/src/world_server.rs

@@ -30,4 +30,28 @@ impl ServerWorld {
             .entry(pos)
             .or_insert_with(|| self.generator.generate_chunk(pos))
     }
+
+    /// Generates and caches all chunks in a cylindrical region around the given position.
+    pub fn load_around(&mut self, center_x: f64, center_y: f64, center_z: f64, radius: i32) {
+        let center = ChunkPos::from_world(center_x, center_y, center_z);
+
+        // Counts the chunks inside the cylinder that were generated or already resident.
+        let mut count = 0;
+
+        for x in center.x - radius..=center.x + radius {
+            for z in center.z - radius..=center.z + radius {
+                for y in center.y - radius / 2..=center.y + radius / 2 {
+                    let dx = x - center.x;
+                    let dz = z - center.z;
+
+                    if (dx * dx + dz * dz) <= radius * radius {
+                        self.get_chunk(ChunkPos::new(x, y, z));
+                        count += 1;
+                    }
+                }
+            }
+        }
+
+        tracing::info!(chunks = count, center = ?center, radius, "loaded chunk cylinder");
+    }
 }