More minimal game state

I'd prefer to start with just the state that I need, and progressively
readd the bits that I've skipped as I find I need them, or as the
competition evolves.

1 files changed, 56 insertions, 0 deletions

diff --git a/src/geometry/direction.rs b/src/geometry/direction.rs
new file mode 100644
index 0000000..84fe785
--- /dev/null
+++ b/src/geometry/direction.rs
@@ -0,0 +1,56 @@
+use std::fmt;
+use crate::geometry::vec::Vec2d;
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum Direction {
+    North,
+    NorthEast,
+    East,
+    SouthEast,
+    South,
+    SouthWest,
+    West,
+    NorthWest,
+}
+
+impl fmt::Display for Direction {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        use Direction::*;
+        let s = match self {
+            North => "N",
+            NorthEast => "NE",
+            East => "E",
+            SouthEast => "SE",
+            South => "S",
+            SouthWest => "SW",
+            West => "W",
+            NorthWest => "NW",
+        };
+        f.write_str(s)
+    }
+}
+
+impl Direction {
+    pub fn is_diagonal(&self) -> bool {
+        use Direction::*;
+
+        match self {
+            NorthEast | SouthEast | SouthWest | NorthWest => true,
+            _ => false,
+        }
+    }
+
+    pub fn as_vec(&self) -> Vec2d<i8> {
+        use Direction::*;
+        match self {
+            North => Vec2d::new(0, -1),
+            NorthEast => Vec2d::new(1, -1),
+            East => Vec2d::new(1, 0),
+            SouthEast => Vec2d::new(1, 1),
+            South => Vec2d::new(0, 1),
+            SouthWest => Vec2d::new(-1, 1),
+            West => Vec2d::new(-1, 0),
+            NorthWest => Vec2d::new(-1, -1),
+        }
+    }
+}