Extract rule stuffs to module

src/falling_sand/mod.rs

@@ -1,4 +1,4 @@
-use std::collections::HashMap;
+mod rules;
 
 use bevy::{
     app::{Plugin, Startup},
@@ -17,6 +17,8 @@ use rand::Rng;
 
 use crate::util::DirtyRect;
 
+use self::rules::{to_rule_state, FallingSandRules};
+
 pub struct FallingSandPlugin;
 
 impl Plugin for FallingSandPlugin {
@@ -239,74 +241,3 @@ impl From<u32> for Element {
         }
     }
 }
-
-fn gen_rule(
-    input: (Element, Element, Element, Element),
-    output: (Element, Element, Element, Element),
-) -> (u32, u32) {
-    (to_rule_state(input), to_rule_state(output))
-}
-
-fn to_rule_state(input: (Element, Element, Element, Element)) -> u32 {
-    ((input.0 as u32) << 24) + ((input.1 as u32) << 16) + ((input.2 as u32) << 8) + input.3 as u32
-}
-
-#[derive(Resource)]
-pub struct FallingSandRules {
-    rules: HashMap<u32, u32>,
-}
-
-impl Default for FallingSandRules {
-    fn default() -> Self {
-        // Pre-computed air-sand rules
-        Self {
-            rules: HashMap::from([
-                gen_rule(
-                    (Element::Air, Element::Sand, Element::Air, Element::Air),
-                    (Element::Air, Element::Air, Element::Air, Element::Sand),
-                ),
-                gen_rule(
-                    (Element::Air, Element::Sand, Element::Air, Element::Sand),
-                    (Element::Air, Element::Air, Element::Sand, Element::Sand),
-                ),
-                gen_rule(
-                    (Element::Air, Element::Sand, Element::Sand, Element::Air),
-                    (Element::Air, Element::Air, Element::Sand, Element::Sand),
-                ),
-                gen_rule(
-                    (Element::Sand, Element::Air, Element::Air, Element::Air),
-                    (Element::Air, Element::Air, Element::Sand, Element::Air),
-                ),
-                gen_rule(
-                    (Element::Sand, Element::Air, Element::Air, Element::Sand),
-                    (Element::Air, Element::Air, Element::Sand, Element::Sand),
-                ),
-                gen_rule(
-                    (Element::Sand, Element::Air, Element::Sand, Element::Air),
-                    (Element::Air, Element::Air, Element::Sand, Element::Sand),
-                ),
-                gen_rule(
-                    (Element::Sand, Element::Sand, Element::Air, Element::Air),
-                    (Element::Air, Element::Air, Element::Sand, Element::Sand),
-                ),
-                gen_rule(
-                    (Element::Sand, Element::Sand, Element::Air, Element::Sand),
-                    (Element::Air, Element::Sand, Element::Sand, Element::Sand),
-                ),
-                gen_rule(
-                    (Element::Sand, Element::Sand, Element::Sand, Element::Air),
-                    (Element::Sand, Element::Air, Element::Sand, Element::Sand),
-                ),
-            ]),
-        }
-    }
-}
-
-impl FallingSandRules {
-    pub fn get_result(&self, input_rule: u32) -> u32 {
-        match self.rules.get(&input_rule) {
-            Some(&result) => result,
-            None => input_rule,
-        }
-    }
-}

src/falling_sand/rules.rs

@@ -0,0 +1,76 @@
+use std::collections::HashMap;
+
+use bevy::ecs::system::Resource;
+
+use super::Element;
+
+#[derive(Resource)]
+pub struct FallingSandRules {
+    rules: HashMap<u32, u32>,
+}
+
+impl Default for FallingSandRules {
+    fn default() -> Self {
+        // Pre-computed air-sand rules
+        Self {
+            rules: HashMap::from([
+                gen_rule(
+                    (Element::Air, Element::Sand, Element::Air, Element::Air),
+                    (Element::Air, Element::Air, Element::Air, Element::Sand),
+                ),
+                gen_rule(
+                    (Element::Air, Element::Sand, Element::Air, Element::Sand),
+                    (Element::Air, Element::Air, Element::Sand, Element::Sand),
+                ),
+                gen_rule(
+                    (Element::Air, Element::Sand, Element::Sand, Element::Air),
+                    (Element::Air, Element::Air, Element::Sand, Element::Sand),
+                ),
+                gen_rule(
+                    (Element::Sand, Element::Air, Element::Air, Element::Air),
+                    (Element::Air, Element::Air, Element::Sand, Element::Air),
+                ),
+                gen_rule(
+                    (Element::Sand, Element::Air, Element::Air, Element::Sand),
+                    (Element::Air, Element::Air, Element::Sand, Element::Sand),
+                ),
+                gen_rule(
+                    (Element::Sand, Element::Air, Element::Sand, Element::Air),
+                    (Element::Air, Element::Air, Element::Sand, Element::Sand),
+                ),
+                gen_rule(
+                    (Element::Sand, Element::Sand, Element::Air, Element::Air),
+                    (Element::Air, Element::Air, Element::Sand, Element::Sand),
+                ),
+                gen_rule(
+                    (Element::Sand, Element::Sand, Element::Air, Element::Sand),
+                    (Element::Air, Element::Sand, Element::Sand, Element::Sand),
+                ),
+                gen_rule(
+                    (Element::Sand, Element::Sand, Element::Sand, Element::Air),
+                    (Element::Sand, Element::Air, Element::Sand, Element::Sand),
+                ),
+            ]),
+        }
+    }
+}
+
+impl FallingSandRules {
+    pub fn get_result(&self, input_rule: u32) -> u32 {
+        match self.rules.get(&input_rule) {
+            Some(&result) => result,
+            None => input_rule,
+        }
+    }
+}
+
+pub fn to_rule_state(input: (Element, Element, Element, Element)) -> u32 {
+    ((input.0 as u32) << 24) + ((input.1 as u32) << 16) + ((input.2 as u32) << 8) + input.3 as u32
+}
+
+fn gen_rule(
+    input: (Element, Element, Element, Element),
+    output: (Element, Element, Element, Element),
+) -> (u32, u32) {
+    (to_rule_state(input), to_rule_state(output))
+}