Flashcards in this deck (41)

• What does import pygame do in a Python game file?

  Imports the Pygame library, giving access to graphics, sound, and input functions.
  pygame setup
• Why use from pygame.locals import *?

  Imports constants like QUIT, K_UP, K_DOWN so they can be used without the pygame.locals. prefix.
  pygame setup
• What does pygame.init() do?

  Initializes all Pygame modules (font, mixer, display, etc.) and must be called before most Pygame functions.
  pygame setup
• What is the purpose of setting fps = 60?

  Sets the target frames per second, controlling how many times the game loop runs per second and game speed.
  pygame timing
• What does fpsClock = pygame.time.Clock() create?

  Creates a Clock object used to control the frame rate by calling .tick(fps) each loop.
  pygame timing
• What do width, height = 640, 480 define?

  Defines the width and height in pixels of the game window.
  pygame display
• What does screen = pygame.display.set_mode((width, height)) do?

  Creates the game window Surface where everything will be drawn.
  pygame display
• What is TILE_WIDTH = 16 used for in an isometric grid?

  Specifies the width (base) in pixels of one isometric tile, affecting horizontal spacing.
  isometric tiles
• Why calculate TILE_WIDTH_HALF = TILE_WIDTH/2?

  Pre-calculates half the tile width to speed up isometric conversion formulas.
  isometric tiles
• What is TILE_HEIGHT = 8 used for in an isometric grid?

  Specifies the height (base) in pixels of one isometric tile, affecting vertical spacing.
  isometric tiles
• Why calculate TILE_HEIGHT_HALF = TILE_HEIGHT/2?

  Pre-calculates half the tile height for use in isometric conversion formulas.
  isometric tiles
• What does class Player(): define?

  Defines a Player object type that bundles data (position, image) and behaviors (update, render).
  python classes
• What is the role of def __init__(self, gridx, gridy, image): in the Player class?

  Constructor method that runs when creating a Player and sets up its initial state.
  python classes
• What does self.gridx represent for a Player?

  The player's column on the logical isometric grid used for movement logic.
  isometric player
• What does self.gridy represent for a Player?

  The player's row on the logical isometric grid used for movement logic.
  isometric player
• What is stored in self.image for a Player?

  The Pygame Surface (picture) that represents the player on screen.
  pygame player
• What is the isometric formula for a Player's screen X coordinate?

  The formula is \(\text{self.x} = (\text{self.gridx} - \text{self.gridy}) \times \text{TILE\_WIDTH\_HALF}\).
  isometric formulas
• What is the isometric formula for a Player's screen Y coordinate?

  The formula is \(\text{self.y} = (\text{self.gridx} + \text{self.gridy}) \times \text{TILE\_HEIGHT\_HALF}\).
  isometric formulas
• What does def update(self, udlr): do in the Player class?

  Method that changes the player's state (position) based on input and is called once per frame.
  python player
• What is the udlr parameter passed to Player.update?

  A tuple of four booleans (up, down, left, right) indicating which arrow keys are pressed.
  input player
• What does u, d, l, r = udlr accomplish inside update?

  Unpacks the udlr tuple into four variables for easier use inside the method.
  python player
• What happens when if u: self.gridy -= 1 executes?

  If the up arrow is pressed, the player's grid row decreases, moving the player up on the grid.
  input movement
• What happens when elif d: self.gridy += 1 executes?

  If the down arrow is pressed, the player's grid row increases, moving the player down on the grid.
  input movement
• What happens when elif l: self.gridx -= 1 executes?

  If the left arrow is pressed, the player's grid column decreases, moving the player left on the grid.
  input movement
• What happens when elif r: self.gridx += 1 executes?

  If the right arrow is pressed, the player's grid column increases, moving the player right on the grid.
  input movement
• Why recalculate self.x and self.y at the end of update?

  To update the player's screen position after changing the grid coordinates using the isometric formulas.
  isometric player
• What does update recalculate after the grid position changes?

  Recalculates the screen Y position after the grid position has changed.
  player update
• What is the purpose of def render(self, screen): in the Player class?

  A method that draws the player onto the given screen surface at its current screen coordinates.
  player render
• What does screen.blit(self.image, (self.x, self.y)) do?

  Copies the player's image onto the screen at the calculated position.
  render blit
• What does pygame.image.load('player.png').convert_alpha() do?

  Loads an image file from disk and optimises it for fast drawing with transparency.
  assets image
• What does player = Player(30, 30, player_img) create?

  Creates a Player object starting at grid position (30,30) using the loaded image.
  player instance
• What is the role of while True: in a Pygame program?

  The infinite loop that keeps the game running; each iteration is one frame.
  loop game
• What does for event in pygame.event.get(): do?

  Loops through all events (key presses, mouse clicks, window closing) since the last frame.
  events input
• What does if event.type == QUIT: check for?

  Checks if the user clicked the window's close button so the game should exit.
  events quit
• Why are pygame.quit() and exit() used together?

  pygame.quit() uninitialises Pygame; exit() stops the Python script to quit cleanly.
  quit cleanup
• What does screen.fill((30, 30, 30)) accomplish each frame?

  Fills the entire screen with a dark grey colour and erases everything from the previous frame.
  render screen
• What does inputs = pygame.key.get_pressed() return?

  The current state of all keyboard keys as a list where each index is a key with True/False.
  input keyboard
• What is inputs_udlr = (inputs[K_UP], inputs[K_DOWN], inputs[K_LEFT], inputs[K_RIGHT]) used for?

  Creates a tuple of the four arrow key states to pass to the player's update method.
  input controls
• What does player.update(inputs_udlr) do in the main loop?

  Calls the player's update method, passing arrow key states so the player can move.
  player update
• What is the effect of pygame.display.flip()?

  Updates the entire screen to show everything drawn since the last flip, making the new frame visible.
  display flip
• What does fpsClock.tick(fps) control?

  Pauses enough to keep the loop running at the target FPS, preventing the game from running too fast.
  performance timing