Cleanup AI code

lib/Canvas.cpp

@@ -80,7 +80,7 @@ void Canvas::renderMaze() {
 
 void Canvas::renderPellets(const Pellets & pellets) {
   Sprite pellet = getSprite(pellets.currentSprite());
-  std::vector<GridPosition> pelletPositions = pellets.currentPositions();
+  std::vector<GridPosition> pelletPositions = pellets.allPellets();
   for (const auto & pos : pelletPositions) {
     renderSprite(pellet, gridPositionToPosition(pos));
   }
@@ -88,7 +88,7 @@ void Canvas::renderPellets(const Pellets & pellets) {
 
 void Canvas::renderSuperPellets(const SuperPellets & superPellets) {
   Sprite pellet = getSprite(superPellets.currentSprite());
-  std::vector<GridPosition> superPelletPositions = superPellets.currentPositions();
+  std::vector<GridPosition> superPelletPositions = superPellets.allPellets();
   for (const auto & pos : superPelletPositions) {
     renderSprite(pellet, gridPositionToPosition(pos));
   }

lib/GameState.cpp

@@ -8,7 +8,10 @@ constexpr int POWER_PELLET_POINTS = 50;
 
 void GameState::step(std::chrono::milliseconds delta) {
   pacManAI.update(pacMan, pellets);
-  pacMan.update(delta, inputState.direction());
+  pacMan.update(delta,
+                pacManAI.suggestedDirection()
+                //inputState.direction()
+  );
 
   if (isPacManDying()) {
     handleDeathAnimation(delta);
@@ -59,6 +62,7 @@ void GameState::handleDeathAnimation(std::chrono::milliseconds delta) {
     pinky.reset();
     inky.reset();
     pacMan.reset();
+    pacManAI.reset();
     timeSinceDeath = std::chrono::milliseconds(0);
   }
 }

lib/PacManAI.cpp

@@ -4,44 +4,66 @@
 #include <fmt/format.h>
 
 namespace pacman {
+
+void PacManAI::reset() {
+  pos = {};
+  direction = Direction::RIGHT;
+}
+
 Direction PacManAI::suggestedDirection() const {
   return direction;
 }
 
+GridPosition PacManAI::pelletClosestToPacman(GridPosition pacmanGridPosition,
+                                             const Pellets & pellets) {
+  auto pelletPositions = pellets.allPellets();
+  auto pelletSort = [&pacmanGridPosition](GridPosition pelletA, GridPosition pelletB) {
+    double distanceA = positionDistance(pacmanGridPosition, pelletA);
+    double distanceB = positionDistance(pacmanGridPosition, pelletB);
+    return distanceA < distanceB;
+  };
+  std::sort(pelletPositions.begin(), pelletPositions.end(), pelletSort);
+  return pelletPositions[0];
+}
+
+bool PacManAI::isValidMove(const Move & move) {
+  const bool isOpposite = (move.direction == oppositeDirection(direction));
+  if (isOpposite) {
+    return false;
+  }
+
+  const bool canWalk = isWalkableForPacMan(move.position);
+  if (!canWalk) {
+    return false;
+  }
+  return true;
+}
+
+Direction PacManAI::optimalDirection(const std::array<Move, 4> & moves) {
+  const auto optimalMove = std::min_element(moves.begin(), moves.end(), [](const auto & a, const auto & b) {
+    return a.distanceToTarget < b.distanceToTarget;
+  });
+
+  const auto & move = *optimalMove;
+  return move.direction;
+}
+
 void PacManAI::update(const PacMan & pacMan, const Pellets & pellets) {
   const GridPosition pacManGridPos = pacMan.positionInGrid();
   const GridPosition currentGridPos = positionToGridPosition(pos);
-  if (currentGridPos == pacManGridPos) {
+
+  if (!isIntersection(pacManGridPos) || currentGridPos == pacManGridPos) {
     return;
   }
 
-  pos = gridPositionToPosition(pacManGridPos);
+  const auto & pelletPositions = pellets.allPellets();
-
-  if (!isIntersection(pacManGridPos)) {
-    return;
-  }
-
-  auto pelletPositions = pellets.currentPositions();
   if (pelletPositions.empty()) {
     return;
   }
-  auto pelletSort = [&pacManGridPos](GridPosition pelletA, GridPosition pelletB) {
-    double distanceA = positionDistance(pacManGridPos, pelletA);
-    double distanceB = positionDistance(pacManGridPos, pelletB);
-    return distanceA < distanceB;
-  };
-  std::sort(pelletPositions.begin(), pelletPositions.end(), pelletSort);
 
-  const auto & target = pelletPositions[0];
+  const GridPosition targetPos = pelletClosestToPacman(pacManGridPos, pellets);
-  const Position targetPos{ double(target.x), double(target.y) };
 
-  struct Move {
+  const GridPosition currentPosition = pacMan.positionInGrid();
-    Direction direction = Direction::NONE;
-    Position position;
-    double distanceToTarget = std::numeric_limits<double>::infinity();
-  };
-
-  const Position currentPosition = { double(pacManGridPos.x), double(pacManGridPos.y) };
   const auto [x, y] = currentPosition;
   std::array<Move, 4> possibleMoves = {
     Move{ Direction::UP, { x, y - 1 } },
@@ -51,30 +73,10 @@ void PacManAI::update(const PacMan & pacMan, const Pellets & pellets) {
   };
 
   for (auto & move : possibleMoves) {
-    const bool invalidPosition = (move.position.x < 0 || move.position.y < 0);
+    if (!isValidMove(move))
-    if (invalidPosition) {
       continue;
-    }
-
-    const bool isOpposite = (move.direction == oppositeDirection(direction));
-    if (isOpposite) {
-      continue;
-    }
-
-    const GridPosition gridMove = { size_t(move.position.x), size_t(move.position.y) };
-    const bool canWalk = isWalkableForPacMan(gridMove);
-    if (!canWalk) {
-      continue;
-    }
-
     move.distanceToTarget = positionDistance(move.position, targetPos);
   }
-
+  direction = optimalDirection(possibleMoves);
-  const auto optimalMove = std::min_element(possibleMoves.begin(), possibleMoves.end(), [](const auto & a, const auto & b) {
-    return a.distanceToTarget < b.distanceToTarget;
-  });
-
-  const auto & move = *optimalMove;
-  direction = move.direction;
 }
 } // namespace pacman

lib/include/PacManAI.hpp

@@ -13,8 +13,19 @@ namespace pacman {
 
 class PacManAI {
 public:
+  struct Move {
+    Direction direction = Direction::NONE;
+    GridPosition position;
+    double distanceToTarget = std::numeric_limits<double>::infinity();
+  };
+
   void update(const PacMan & pacMan, const Pellets & pellets);
   Direction suggestedDirection() const;
+  GridPosition pelletClosestToPacman(GridPosition pacmanGridPosition,
+                                     const Pellets & pellets);
+  bool isValidMove(const Move & move);
+  Direction optimalDirection(const std::array<Move, 4> & moves);
+  void reset();
 
 private:
   Position pos;

lib/include/Pellets.hpp

@@ -13,7 +13,7 @@ public:
     return sprite;
   };
 
-  std::vector<GridPosition> currentPositions() const {
+  std::vector<GridPosition> allPellets() const {
     return positions;
   }
 

lib/include/SuperPellets.hpp

@@ -13,7 +13,7 @@ public:
     return sprite;
   }
 
-  std::vector<GridPosition> currentPositions() const {
+  std::vector<GridPosition> allPellets() const {
     return positions;
   }
 

test/testPellets.cpp

@@ -4,7 +4,7 @@
 
 template<typename T>
 static void pelletInitTest(const T & pellets, size_t size, size_t spriteX, size_t spriteY) {
-  REQUIRE(pellets.currentPositions().size() == size);
+  REQUIRE(pellets.allPellets().size() == size);
   REQUIRE(pellets.currentSprite().x == spriteX);
   REQUIRE(pellets.currentSprite().y == spriteY);
 }
@@ -19,13 +19,13 @@ TEST_CASE("Pellet initialization", "[pellets]") {
 
 template<typename T>
 static void pelletEatingTest(T & pellets, size_t countBefore, size_t countAfter, size_t x, size_t y) {
-  REQUIRE(pellets.currentPositions().size() == countBefore);
+  REQUIRE(pellets.allPellets().size() == countBefore);
   if (countBefore != countAfter) {
     REQUIRE(pellets.eatPelletAtPosition(pacman::GridPosition{ x, y }));
   } else {
     REQUIRE_FALSE(pellets.eatPelletAtPosition(pacman::GridPosition{ x, y }));
   }
-  REQUIRE(pellets.currentPositions().size() == countAfter);
+  REQUIRE(pellets.allPellets().size() == countAfter);
 }
 
 TEST_CASE("Eating pellets", "[pellets]") {