// 第 6 步：吃豆子——吃光所有豆子就贏了！
#include <cstdlib>
#include <string>
#include "GridPlusPlus.h"
using gridpp::GameEngine;
using gridpp::GridObject;
using gridpp::Maze;
using gridpp::Overlay;
const int kCols = 15;
const int kRows = 11;
const char* kMap[kRows] = {
"###############",
"#P............#",
"#.#.###.###.#.#",
"#.............#",
"#.#.#.#.#.#.#.#",
"#.............#",
"#.#.#.#.#.#.#.#",
"#.............#",
"#.#.###.###.#.#",
"#............G#",
"###############",
}; // '#' 是牆，'P' 是小精靈的起點，'G' 是鬼的起點
Maze maze;
GridObject pacman;
Overlay message;
bool game_over = false;
Overlay score_label;
int score = 0;
int pellets_left = 0;
// 讓 who 往 (dx, dy) 走一格；前面是牆就不動。
void Walk(GridObject who, int dx, int dy) {
if (maze.isWall(who.x() + dx, who.y() + dy)) return;
who.move(dx, dy);
}
void GameOver() {
game_over = true;
message.setText("GAME OVER");
message.show();
}
void Win() {
game_over = true;
message.setText("YOU WIN!");
message.setColor(YELLOW);
message.show();
}
// 豆子和別的東西撞在同一格時，Engine 會呼叫這個函式。
void EatPellet(GameEngine, GridObject self, GridObject other) {
if (other.image() != "pacman") return; // 鬼經過不算，只有小精靈會吃豆子
self.remove();
score += 10;
score_label.setText("Score: " + std::to_string(score));
pellets_left--;
if (pellets_left == 0) Win();
}
// 小精靈和別的東西撞在同一格時，Engine 會呼叫這個函式。
void PacmanHit(GameEngine, GridObject, GridObject other) {
if (other.image() == "ghost") GameOver();
}
void MovePacman(GameEngine game, GridObject self) {
if (game_over) return;
if (game.keyPressed(KEY_RIGHT)) {
self.setDirection(0);
Walk(self, 1, 0);
}
if (game.keyPressed(KEY_UP)) {
self.setDirection(1);
Walk(self, 0, -1);
}
if (game.keyPressed(KEY_LEFT)) {
self.setDirection(2);
Walk(self, -1, 0);
}
if (game.keyPressed(KEY_DOWN)) {
self.setDirection(3);
Walk(self, 0, 1);
}
}
const int kDX[4] = {1, 0, -1, 0}; // 方向 0 右、1 上、2 左、3 下
const int kDY[4] = {0, -1, 0, 1};
int ghost_direction = 2;
double ghost_next_move = 0;
// 鬼是不是和小精靈在同一格？
bool Caught(GridObject ghost) { return ghost.x() == pacman.x() && ghost.y() == pacman.y(); }
void ChasePacman(GameEngine game, GridObject self) {
if (game_over) return;
if (game.time() < ghost_next_move) return; // 還沒輪到鬼走
ghost_next_move = game.time() + 0.3;
// 走之前先看一眼：小精靈是不是自己撞上來了？
if (Caught(self)) {
GameOver();
return;
}
// 看看四個方向，選一條離小精靈最近、而且不用回頭的路。
int back = (ghost_direction + 2) % 4;
int best = back; // 四面都走不通（死路）的時候，只好回頭
int best_distance = 9999;
for (int d = 0; d < 4; ++d) {
if (d == back) continue;
int x = self.x() + kDX[d];
int y = self.y() + kDY[d];
if (maze.isWall(x, y)) continue;
int distance = std::abs(x - pacman.x()) + std::abs(y - pacman.y());
if (distance < best_distance) {
best = d;
best_distance = distance;
}
}
ghost_direction = best;
self.move(kDX[best], kDY[best]);
// 走完再看一眼：是不是撲到小精靈身上了？
if (Caught(self)) GameOver();
}
int main() {
GameEngine game(kCols, kRows, 48);
game.loadAssets("pacman.db");
game.setBackgroundColor(BLACK);
maze = game.addMaze(kCols, kRows);
maze.setWallImages("wall_iso", "wall_end", "wall_straight", "wall_corner", "wall_tee", "wall_cross");
for (int y = 0; y < kRows; ++y) {
for (int x = 0; x < kCols; ++x) {
if (kMap[y][x] == '#') {
maze.setWall(x, y);
} else if (kMap[y][x] == '.') {
GridObject pellet = game.addObject("pellet", nullptr, nullptr, EatPellet);
pellet.setPosition(x, y);
pellets_left++;
}
}
}
pacman = game.addObject("pacman", nullptr, MovePacman, PacmanHit);
pacman.setPosition(1, 1);
GridObject ghost = game.addObject("ghost", nullptr, ChasePacman);
ghost.setPosition(13, 9);
ghost.setColor(RED);
message = game.addTextOverlay("GAME OVER", 195, 230, 60, RED);
message.hide();
score_label = game.addTextOverlay("Score: 0", 10, 10, 24, WHITE);
game.run();
return 0;
}
