Sketch 2026-03-01 22:19

function setup() {
  createCanvas(windowWidth, windowHeight);

  player = {
    x: width / 2,
    y: height - 80,
    w: 50,
    h: 30,
    speed: 7
  };

  resetGame(false); // set initial values but stay on start screen
}

function resetGame(startImmediately = true) {
  bullets = [];
  enemies = [];
  score = 0;
  lives = 3;
  enemySpawnInterval = 60;
  lastEnemySpawnFrame = frameCount;
  player.x = width / 2;
  player.y = height - 80;

  if (startImmediately) {
    gameState = 'playing';
  }
}

function draw() {
  background(10);

  if (gameState === 'start') {
    drawStartScreen();
  } else if (gameState === 'playing') {
    updateGame();
    drawGame();
  } else if (gameState === 'gameOver') {
    drawGame();
    drawGameOverScreen();
  }
}

function updateGame() {
  handlePlayerMovement();
  handleShooting();
  spawnEnemies();
  updateBullets();
  updateEnemies();
  checkCollisions();
}

function handlePlayerMovement() {
  if (keyIsDown(LEFT_ARROW) || keyIsDown(65)) { // LEFT or 'A'
    player.x -= player.speed;
  }
  if (keyIsDown(RIGHT_ARROW) || keyIsDown(68)) { // RIGHT or 'D'
    player.x += player.speed;
  }
  player.x = constrain(player.x, player.w / 2, width - player.w / 2);
}

function handleShooting() {
  // Shooting is handled in keyPressed() (one shot per press)
}

function spawnEnemies() {
  if (frameCount - lastEnemySpawnFrame > enemySpawnInterval) {
    const enemyWidth = random(30, 50);
    enemies.push({
      x: random(enemyWidth / 2, width - enemyWidth / 2),
      y: -30,
      w: enemyWidth,
      h: 30,
      speed: random(2, 5)
    });
    lastEnemySpawnFrame = frameCount;

    // Gradually make game harder: faster spawns
    if (enemySpawnInterval > 25) {
      enemySpawnInterval -= 0.2;
    }
  }
}

function updateBullets() {
  for (let i = bullets.length - 1; i >= 0; i--) {
    let b = bullets[i];
    b.y -= b.speed;
    if (b.y + b.h / 2 < 0) {
      bullets.splice(i, 1);
    }
  }
}

function updateEnemies() {
  for (let i = enemies.length - 1; i >= 0; i--) {
    let e = enemies[i];
    e.y += e.speed;

    // Enemy reached bottom: lose a life
    if (e.y - e.h / 2 > height) {
      enemies.splice(i, 1);
      lives--;
      if (lives <= 0) {
        gameState = 'gameOver';
      }
    }
  }
}

function checkCollisions() {
  // Bullet vs Enemy
  for (let i = bullets.length - 1; i >= 0; i--) {
    let b = bullets[i];
    for (let j = enemies.length - 1; j >= 0; j--) {
      let e = enemies[j];
      if (rectOverlap(b, e)) {
        // Remove both and increase score
        bullets.splice(i, 1);
        enemies.splice(j, 1);
        score++;

        // Slightly increase difficulty as score increases
        break; // break enemy loop for this bullet
      }
    }
  }

  // Player vs Enemy
  for (let i = enemies.length - 1; i >= 0; i--) {
    let e = enemies[i];
    if (rectOverlap(player, e)) {
      enemies.splice(i, 1);
      lives--;
      if (lives <= 0) {
        gameState = 'gameOver';
      }
    }
  }
}

function rectOverlap(a, b) {
  return !(
    a.x + a.w / 2 < b.x - b.w / 2 ||
    a.x - a.w / 2 > b.x + b.w / 2 ||
    a.y + a.h / 2 < b.y - b.h / 2 ||
    a.y - a.h / 2 > b.y + b.h / 2
  );
}

function drawGame() {
  // Player
  rectMode(CENTER);
  noStroke();
  fill(0, 200, 255);
  rect(player.x, player.y, player.w, player.h);

  // Player "nose" (triangle) to make it look like a ship
  fill(0, 255, 150);
  triangle(
    player.x, player.y - player.h / 2 - 10,
    player.x - player.w / 4, player.y,
    player.x + player.w / 4, player.y
  );

  // Bullets
  fill(255, 255, 0);
  for (let b of bullets) {
    rect(b.x, b.y, b.w, b.h);
  }

  // Enemies
  fill(255, 80, 80);
  for (let e of enemies) {
    rect(e.x, e.y, e.w, e.h);
  }

  // UI: Score and Lives
  fill(255);
  textSize(20);
  textAlign(LEFT, TOP);
  text('Score: ' + score, 15, 10);

  textAlign(RIGHT, TOP);
  text('Lives: ' + lives, width - 15, 10);
}

function drawStartScreen() {
  background(10);
  fill(255);
  textAlign(CENTER, CENTER);

  textSize(48);
  text('Space Shooter', width / 2, height / 2 - 60);

  textSize(24);
  text('Move: Arrow Keys or A/D', width / 2, height / 2);
  text('Shoot: Spacebar', width / 2, height / 2 + 30);
  text('Press ENTER to Start', width / 2, height / 2 + 80);
}

function drawGameOverScreen() {
  fill(0, 0, 0, 170);
  rectMode(CORNER);
  noStroke();
  rect(0, 0, width, height);

  fill(255);
  textAlign(CENTER, CENTER);
  textSize(48);
  text('Game Over', width / 2, height / 2 - 60);

  textSize(28);
  text('Final Score: ' + score, width / 2, height / 2);

  textSize(22);
  text('Press R to Restart', width / 2, height / 2 + 50);
}

function keyPressed() {
  if (gameState === 'start' && keyCode === ENTER) {
    resetGame(true);
  }

  if (gameState === 'gameOver' && (key === 'r' || key === 'R')) {
    resetGame(true);
  }

  // Shooting
  if (gameState === 'playing' && key === ' ') {
    bullets.push({
      x: player.x,
      y: player.y - player.h / 2 - 10,
      w: 6,
      h: 16,
      speed: 10
    });
  }
}

function windowResized() {
  resizeCanvas(windowWidth, windowHeight);
  // Keep player near bottom center when resized
  player.x = width / 2;
  player.y = height - 80;
}