add checkers game tutorial

Author: x4nth055

README.md

@@ -278,5 +278,6 @@ This is a repository of all the tutorials of [The Python Code](https://www.thepy
     - [How to Build a Tic Tac Toe Game in Python](https://www.thepythoncode.com/article/make-a-tic-tac-toe-game-pygame-in-python). ([code](gui-programming/tictactoe-game))
     - [How to Build a GUI Language Translator App in Python](https://www.thepythoncode.com/article/build-a-gui-language-translator-tkinter-python). ([code](gui-programming/gui-language-translator))
     - [How to Make an Image Editor in Python](https://www.thepythoncode.com/article/make-an-image-editor-in-tkinter-python). ([code](gui-programming/image-editor))
+    - [How to Make a Checkers Game with Pygame in Python](https://www.thepythoncode.com/article/make-a-checkers-game-with-pygame-in-python). ([code](gui-programming/checkers-game))
 
 For any feedback, please consider pulling requests.

gui-programming/checkers-game/Board.py

@@ -0,0 +1,84 @@
+import pygame
+from Tile import Tile
+from Pawn import Pawn
+
+class Board:
+	def __init__(self,tile_width, tile_height, board_size):
+		self.tile_width = tile_width
+		self.tile_height = tile_height
+		self.board_size = board_size
+		self.selected_piece = None
+
+		self.turn = "black"
+		self.is_jump = False
+
+		self.config = [
+			['', 'bp', '', 'bp', '', 'bp', '', 'bp'],
+			['bp', '', 'bp', '', 'bp', '', 'bp', ''],
+			['', 'bp', '', 'bp', '', 'bp', '', 'bp'],
+			['', '', '', '', '', '', '', ''],
+			['', '', '', '', '', '', '', ''],
+			['rp', '', 'rp', '', 'rp', '', 'rp', ''],
+			['', 'rp', '', 'rp', '', 'rp', '', 'rp'],
+			['rp', '', 'rp', '', 'rp', '', 'rp', '']
+		]
+
+		self.tile_list = self._generate_tiles()
+		self._setup()
+
+	def _generate_tiles(self):
+		output = []
+		for y in range(self.board_size):
+			for x in range(self.board_size):
+				output.append(
+					Tile(x,  y, self.tile_width, self.tile_height)
+				)
+		return output
+
+	def get_tile_from_pos(self, pos):
+		for tile in self.tile_list:
+			if (tile.x, tile.y) == (pos[0], pos[1]):
+				return tile
+
+	def _setup(self):
+		for y_ind, row in enumerate(self.config):
+			for x_ind, x in enumerate(row):
+				tile = self.get_tile_from_pos((x_ind, y_ind))
+				if x != '':
+					if x[-1] == 'p':
+						color = 'red' if x[0] == 'r' else 'black'
+						tile.occupying_piece = Pawn(x_ind, y_ind, color, self)
+
+	def handle_click(self, pos):
+		x, y = pos[0], pos[-1]
+		if x >= self.board_size or y >= self.board_size:
+			x = x // self.tile_width
+			y = y // self.tile_height
+		clicked_tile = self.get_tile_from_pos((x, y))
+
+		if self.selected_piece is None:
+			if clicked_tile.occupying_piece is not None:
+				if clicked_tile.occupying_piece.color == self.turn:
+					self.selected_piece = clicked_tile.occupying_piece
+		elif self.selected_piece._move(clicked_tile):
+			if not self.is_jump:
+				self.turn = 'red' if self.turn == 'black' else 'black'
+			else:
+				if len(clicked_tile.occupying_piece.valid_jumps()) == 0:
+					self.turn = 'red' if self.turn == 'black' else 'black'
+		elif clicked_tile.occupying_piece is not None:
+			if clicked_tile.occupying_piece.color == self.turn:
+				self.selected_piece = clicked_tile.occupying_piece
+
+	def draw(self, display):
+		if self.selected_piece is not None:
+			self.get_tile_from_pos(self.selected_piece.pos).highlight = True
+			if not self.is_jump:
+				for tile in self.selected_piece.valid_moves():
+					tile.highlight = True
+			else:
+				for tile in self.selected_piece.valid_jumps():
+					tile[0].highlight = True
+
+		for tile in self.tile_list:
+			tile.draw(display)

gui-programming/checkers-game/Game.py

@@ -0,0 +1,44 @@
+class Game:
+
+	def __init__(self):
+		self.winner = None
+
+	# checks if both colors still has a piece
+	def check_piece(self, board):
+		red_piece = 0
+		black_piece = 0
+		for y in range(board.board_size):
+			for x in range(board.board_size):
+				tile = board.get_tile_from_pos((x, y))
+				if tile.occupying_piece != None:
+					if tile.occupying_piece.color == "red":
+						red_piece += 1
+					else:
+						black_piece += 1
+		return red_piece, black_piece
+
+	def is_game_over(self, board):
+		red_piece, black_piece = self.check_piece(board)
+		if red_piece == 0 or black_piece == 0:
+			self.winner = "red" if red_piece > black_piece else "black"
+			return True
+		else:
+			return False
+
+	def check_jump(self, board):
+		piece = None
+		for tile in board.tile_list:
+			if tile.occupying_piece != None:
+				piece = tile.occupying_piece
+				if len(piece.valid_jumps()) != 0 and board.turn == piece.color:
+					board.is_jump = True
+					break
+				else:
+					board.is_jump = False
+		if board.is_jump:
+			board.selected_piece = piece
+			board.handle_click(piece.pos)
+		return board.is_jump
+
+	def message(self):
+		print(f"{self.winner} Wins!!")

gui-programming/checkers-game/King.py

@@ -0,0 +1,47 @@
+import pygame
+from Piece import Piece
+
+class King(Piece):
+	def __init__(self, x, y, color, board):
+		super().__init__(x, y, color, board)
+		img_path = f'images/{color}-king.png'
+		self.img = pygame.image.load(img_path)
+		self.img = pygame.transform.scale(self.img, (board.tile_width, board.tile_height))
+		self.notation = 'k'
+
+	def _possible_moves(self):
+		possible_moves = ((-1, -1), (+1, -1), (-1, +1), (+1, +1))
+		return possible_moves
+
+	def valid_moves(self):
+		tile_moves = []
+		moves = self._possible_moves()
+		for move in moves:
+			tile_pos = (self.x + move[0], self.y + move[-1])
+			if tile_pos[0] < 0 or tile_pos[0] > 7 or tile_pos[-1] < 0 or tile_pos[-1] > 7:
+				pass
+			else:
+				tile = self.board.get_tile_from_pos(tile_pos)
+				if tile.occupying_piece == None:
+					tile_moves.append(tile)
+		return tile_moves
+
+	def valid_jumps(self):
+		tile_jumps = []
+		moves = self._possible_moves()
+		for move in moves:
+			tile_pos = (self.x + move[0], self.y + move[-1])
+			if tile_pos[0] < 0 or tile_pos[0] > 7 or tile_pos[-1] < 0 or tile_pos[-1] > 7:
+				pass
+			else:
+				tile = self.board.get_tile_from_pos(tile_pos)
+				if self.board.turn == self.color:
+					if tile.occupying_piece != None and tile.occupying_piece.color != self.color:
+						next_pos = (tile_pos[0] + move[0], tile_pos[-1] + move[-1])
+						next_tile = self.board.get_tile_from_pos(next_pos)		
+						if next_pos[0] < 0 or next_pos[0] > 7 or next_pos[-1] < 0 or next_pos[-1] > 7:
+							pass
+						else:
+							if next_tile.occupying_piece == None:
+								tile_jumps.append((next_tile, tile))
+		return tile_jumps

gui-programming/checkers-game/Main.py

@@ -0,0 +1,46 @@
+import pygame
+from Board import Board
+from Game import Game
+
+pygame.init()
+
+class Checkers:
+	def __init__(self, screen):
+		self.screen = screen
+		self.running = True
+		self.FPS = pygame.time.Clock()
+
+	def _draw(self, board):
+		board.draw(self.screen)
+		pygame.display.update()
+
+	def main(self, window_width, window_height):
+		board_size = 8
+		tile_width, tile_height = window_width // board_size, window_height // board_size
+		board = Board(tile_width, tile_height, board_size)
+		game = Game()
+		while self.running:
+			game.check_jump(board)
+
+			for self.event in pygame.event.get():
+				if self.event.type == pygame.QUIT:
+					self.running = False
+
+				if not game.is_game_over(board):
+					if self.event.type == pygame.MOUSEBUTTONDOWN:
+						board.handle_click(self.event.pos)
+				else:
+					game.message()
+					self.running = False
+
+			self._draw(board)
+			self.FPS.tick(60)
+
+
+if __name__ == "__main__":
+	window_size = (640, 640)
+	screen = pygame.display.set_mode(window_size)
+	pygame.display.set_caption("Checkers")
+
+	checkers = Checkers(screen)
+	checkers.main(window_size[0], window_size[1])

gui-programming/checkers-game/Pawn.py

@@ -0,0 +1,51 @@
+import pygame
+from Piece import Piece
+
+class Pawn(Piece):
+	def __init__(self, x, y, color, board):
+		super().__init__(x, y, color, board)
+		img_path = f'images/{color}-pawn.png'
+		self.img = pygame.image.load(img_path)
+		self.img = pygame.transform.scale(self.img, (board.tile_width, board.tile_height))
+		self.notation = 'p'
+
+	def _possible_moves(self):
+		# (x, y) move for left and right
+		if self.color == "red":
+			possible_moves = ((-1, -1), (+1, -1)) 
+		else:
+			possible_moves = ((-1, +1), (+1, +1))
+		return possible_moves
+
+	def valid_moves(self):
+		tile_moves = []
+		moves = self._possible_moves()
+		for move in moves:
+			tile_pos = (self.x + move[0], self.y + move[-1])
+			if tile_pos[0] < 0 or tile_pos[0] > 7 or tile_pos[-1] < 0 or tile_pos[-1] > 7:
+				pass
+			else:
+				tile = self.board.get_tile_from_pos(tile_pos)
+				if tile.occupying_piece == None:
+					tile_moves.append(tile)
+		return tile_moves
+
+	def valid_jumps(self):
+		tile_jumps = []
+		moves = self._possible_moves()
+		for move in moves:
+			tile_pos = (self.x + move[0], self.y + move[-1])
+			if tile_pos[0] < 0 or tile_pos[0] > 7 or tile_pos[-1] < 0 or tile_pos[-1] > 7:
+				pass
+			else:
+				tile = self.board.get_tile_from_pos(tile_pos)
+				if self.board.turn == self.color:
+					if tile.occupying_piece != None and tile.occupying_piece.color != self.color:
+						next_pos = (tile_pos[0] + move[0], tile_pos[-1] + move[-1])
+						next_tile = self.board.get_tile_from_pos(next_pos)		
+						if next_pos[0] < 0 or next_pos[0] > 7 or next_pos[-1] < 0 or next_pos[-1] > 7:
+							pass
+						else:
+							if next_tile.occupying_piece == None:
+								tile_jumps.append((next_tile, tile))
+		return tile_jumps

gui-programming/checkers-game/Piece.py

@@ -0,0 +1,56 @@
+import pygame
+
+class Piece:
+	def __init__(self, x, y, color, board):
+		self.x = x
+		self.y = y
+		self.pos = (x, y)
+		self.board = board
+		self.color = color
+
+	def _move(self, tile):
+		for i in self.board.tile_list:
+			i.highlight = False
+
+		if tile in self.valid_moves() and not self.board.is_jump:
+			prev_tile = self.board.get_tile_from_pos(self.pos)
+			self.pos, self.x, self.y = tile.pos, tile.x, tile.y
+
+			prev_tile.occupying_piece = None
+			tile.occupying_piece = self
+			self.board.selected_piece = None
+			self.has_moved = True
+
+			# Pawn promotion
+			if self.notation == 'p':
+				if self.y == 0 or self.y == 7:
+					from King import King
+					tile.occupying_piece = King(
+						self.x, self.y, self.color, self.board
+					)
+			return True
+
+		elif self.board.is_jump:
+			for move in self.valid_jumps():
+				if tile in move:
+					prev_tile = self.board.get_tile_from_pos(self.pos)
+					jumped_piece = move[-1]
+					self.pos, self.x, self.y = tile.pos, tile.x, tile.y
+
+					prev_tile.occupying_piece = None
+					jumped_piece.occupying_piece = None
+					tile.occupying_piece = self
+					self.board.selected_piece = None
+					self.has_moved = True
+
+					# Pawn promotion
+					if self.notation == 'p':
+						if self.y == 0 or self.y == 7:
+							from King import King
+							tile.occupying_piece = King(
+								self.x, self.y, self.color, self.board
+							)
+					return True
+		else:
+			self.board.selected_piece = None
+			return False

gui-programming/checkers-game/README.md

@@ -0,0 +1,4 @@
+# [How to Make a Checkers Game with Pygame in Python](https://www.thepythoncode.com/article/make-a-checkers-game-with-pygame-in-python)
+To run this:
+- `pip3 install -r requirements.txt`
+- `python3 Main.py`

gui-programming/checkers-game/Tile.py

@@ -0,0 +1,41 @@
+import pygame
+
+class Tile:
+	def __init__(self, x, y, tile_width, tile_height):
+		self.x = x
+		self.y = y
+		self.pos = (x, y)
+		self.tile_width = tile_width
+		self.tile_height = tile_height
+		self.abs_x = x * tile_width
+		self.abs_y = y * tile_height
+		self.abs_pos = (self.abs_x, self.abs_y)
+
+		self.color = 'light' if (x + y) % 2 == 0 else 'dark'
+		self.draw_color = (220, 189, 194) if self.color == 'light' else (53, 53, 53)
+		self.highlight_color = (100, 249, 83) if self.color == 'light' else (0, 228, 10)
+
+		self.occupying_piece = None
+		self.coord = self.get_coord()
+		self.highlight = False
+		self.rect = pygame.Rect(
+			self.abs_x,
+			self.abs_y,
+			self.tile_width,
+			self.tile_height
+		)
+
+	def get_coord(self):
+		columns = 'abcdefgh'
+		return columns[self.x] + str(self.y + 1)
+
+	def draw(self, display):
+		if self.highlight:
+			pygame.draw.rect(display, self.highlight_color, self.rect)
+		else:
+			pygame.draw.rect(display, self.draw_color, self.rect)
+
+		if self.occupying_piece != None:
+			centering_rect = self.occupying_piece.img.get_rect()
+			centering_rect.center = self.rect.center
+			display.blit(self.occupying_piece.img, centering_rect.topleft)

gui-programming/checkers-game/images/black-king.png

@@ -0,0 +1 @@
+pygame