1 files changed, 14 insertions, 0 deletions

@@ -3,6 +3,7 @@
 
 #include <string>
 #include <stdexcept>
+#include "vector.h"
 
 enum class Direction {
   up,
@@ -27,4 +28,17 @@ inline Direction directionFromString(std::string_view str) {
   throw std::invalid_argument("Invalid direction: " + std::string(str));
 }
 
+inline vec2i unitVecInDirection(Direction dir) {
+  switch (dir) {
+    case Direction::up: return { 0, -1 };
+    case Direction::up_right: return { 1, -1 };
+    case Direction::right: return { 1, 0 };
+    case Direction::down_right: return { 1, 1 };
+    case Direction::down: return { 0, 1 };
+    case Direction::down_left: return { -1, 1 };
+    case Direction::left: return { -1, 0 };
+    case Direction::up_left: return { -1, -1 };
+  }
+}
+
 #endif /* end of include guard: DIRECTION_H_AB66A90E */