Initial commit

src/misc/arena.rs

@@ -0,0 +1,52 @@
+#[derive(Debug)]
+pub struct Arena<T> {
+    data: Vec<Option<T>>,
+    free: Vec<usize>,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct ArenaKey(usize);
+
+impl Default for ArenaKey {
+    fn default() -> Self {
+        ArenaKey(usize::MAX)
+    }
+}
+
+impl<T> Arena<T> {
+    pub fn new() -> Self {
+        Self {
+            data: Vec::new(),
+            free: Vec::new(),
+        }
+    }
+
+    pub fn insert(&mut self, item: T) -> ArenaKey {
+        if let Some(i) = self.free.pop() {
+            self.data[i] = Some(item);
+            ArenaKey(i)
+        } else {
+            self.data.push(Some(item));
+            ArenaKey(self.data.len() - 1)
+        }
+    }
+
+    pub fn get(&self, key: &ArenaKey) -> &T {
+        self.data.get(key.0).unwrap().as_ref().unwrap()
+    }
+
+    pub fn get_mut(&mut self, key: &ArenaKey) -> &mut T {
+        self.data.get_mut(key.0).unwrap().as_mut().unwrap()
+    }
+
+    pub fn remove(&mut self, key: ArenaKey) -> T {
+        self.free.push(key.0);
+        self.data[key.0].take().unwrap()
+    }
+}
+
+impl<T> Default for Arena<T> {
+    fn default() -> Self {
+        Self::new()
+    }
+}

src/misc/map.rs

@@ -0,0 +1,45 @@
+pub struct Map<T> {
+    pub width: usize,
+    pub height: usize,
+    data: Vec<T>,
+}
+
+impl<T> Map<T>
+where
+    T: Default,
+{
+    pub fn new(width: usize, height: usize) -> Self {
+        let mut data = Vec::new();
+        for _ in 0..(width * height) {
+            data.push(T::default());
+        }
+
+        Self {
+            width,
+            height,
+            data,
+        }
+    }
+
+    fn index(&self, x: usize, y: usize) -> usize {
+        x + y * self.width
+    }
+
+    pub fn get(&self, x: usize, y: usize) -> &T {
+        assert!(x < self.width);
+        assert!(y < self.height);
+        let i = self.index(x, y);
+        self.data.get(i).unwrap()
+    }
+
+    pub fn get_mut(&mut self, x: usize, y: usize) -> &mut T {
+        assert!(x < self.width);
+        assert!(y < self.height);
+        let i = self.index(x, y);
+        self.data.get_mut(i).unwrap()
+    }
+
+    pub fn set(&mut self, x: usize, y: usize, item: T) {
+        *self.get_mut(x, y) = item;
+    }
+}

src/misc/mod.rs

@@ -0,0 +1,5 @@
+pub mod arena;
+pub mod map;
+
+pub use arena::*;
+pub use map::*;