Simple MineCraft Cline (Remix)

This sketch creates a colorful 2D Minecraft-style sandbox where two players can simultaneously run, jump, mine, and place blocks to reshape the terrain. The world features procedurally-generated terrain, a day/night cycle with zombie spawns at night, and separate keyboard/touch controls for cooperative building.

Open in Editor Remix View in Gallery

🧪 Try This!

Experiment with the code by making these changes:

Change block colors — Grass will appear red instead of green, making the world look alien and unnatural.
Make gravity stronger — Players and zombies will fall faster and harder, making jumps feel snappier and landing impacts heavier.
Increase jump height — Players can reach much higher with a single jump, making the world feel more traversable and adventurous.
Make trees denser — Forests will be much thicker with more trees generated, making the landscape feel more forested and maze-like.
Speed up day/night cycle — Time passes much faster, so day and night alternate quickly, creating a hypnotic time-lapse effect.

Prefer the full editor? Open it there →

📖 About This Sketch

This sketch builds a playable 2D Minecraft clone in p5.js where two players cooperatively explore and reshape a pixel-art world. The landscape is procedurally generated with Perlin noise, featuring grass, dirt, stone, wood, and leaves arranged in realistic terrain with trees. A day/night cycle shifts the sky color and spawns hostile zombies when darkness falls—enemies that hunt toward the nearest player using simple AI. What makes this sketch visually striking is the combination of a scrolling camera centered between both players, colorful block palettes, and the satisfying sound effects when mining or placing blocks.

The code is organized into three core systems: world generation and block management, a physics engine that handles two players and zombie movement with collision detection, and an input handler supporting keyboard (with different control schemes per player), mouse clicks (with world-space coordinate conversion), and touch buttons for mobile devices. By studying it you will learn how to build a procedurally-generated tilemap, implement a camera that tracks multiple entities, manage multi-player input, play procedural audio, and structure a game loop where NPCs have independent AI.

⚙️ How It Works

When the sketch loads, setup() creates a canvas and calls initWorld() to generate terrain using Perlin noise. Each column of the world gets a height value, which determines where grass, dirt, and stone layers form, and occasionally spawns trees made of wood blocks with leaf canopies.
The world array is a 2D grid where each cell holds a block ID (AIR, GRASS, DIRT, STONE, WOOD, or LEAVES). Two player objects are spawned on top of the terrain with separate inventories and control schemes.
Every frame, draw() calls handleInput() to read keyboard/touch, updatePlayer() to apply gravity and collision detection to both players, updateZombies() to move enemies toward the nearest player, and drawWorld() to render only the visible tiles (culled for performance).
The camera centers on the midpoint between both players, constraining to world bounds so players can always see each other. A day/night cycle changes the sky color using lerpColor() transitions and spawns zombies at night with random placement checks to avoid overlapping terrain or players.
When a player clicks/taps the world or presses break/place keys, handleBlockInteraction() converts screen coordinates to tile coordinates (accounting for camera offset), then either breaks the block or places the selected block from their inventory (checking that it won't overlap with players or zombies).
Procedural sound is triggered on actions: playJumpSound() uses a square-wave oscillator, playBlockBreakSound() uses brown noise for a crunch, and playBlockPlaceSound() uses a triangle wave for a high blip—all with envelopes that fade in and out quickly.

🎓 Concepts You'll Learn

Procedural terrain generation with Perlin noise2D tilemap and block grid systemsPhysics simulation with gravity and collision detectionMulti-player input handling and control schemesCamera tracking and viewport cullingAI pathfinding and enemy behaviorTouch input and mobile UI controlsProcedural audio synthesis with oscillators and envelopes

📝 Code Breakdown

`setup()`

setup() runs exactly once when the sketch starts. Use it to initialize canvas size, seed randomness, and create your world data structures.

function setup() {
  createCanvas(windowWidth, windowHeight);
  noiseSeed(floor(random(100000)));
  initWorld();
  isTouchDevice = 'ontouchstart' in window || navigator.maxTouchPoints > 0;
}

Line-by-line explanation (4 lines)

createCanvas(windowWidth, windowHeight);: Creates a canvas that fills the entire browser window so the game is responsive to screen size.
noiseSeed(floor(random(100000)));: Seeds the Perlin noise generator with a random number so each game generates different terrain (without this seed, the terrain would be identical every time).
initWorld();: Calls the world generation function to create the tilemap, terrain, trees, and spawn both players.
isTouchDevice = 'ontouchstart' in window || navigator.maxTouchPoints > 0;: Detects whether the device supports touch input so the sketch can display mobile-friendly button controls if needed.

`draw()`

draw() is p5.js's main loop—it runs 60 times per second by default. Here, we update the world state (time, player physics, zombie AI), then render everything. This is where the magic happens: every frame is a tiny incremental change that creates the illusion of continuous animation and interaction.

🔬 The cycle speed controls how fast time passes. What happens if you change CYCLE_SPEED from 0.02 to 0.2? Does the day/night cycle speed up, and do zombies spawn more often?

  currentTime += CYCLE_SPEED;
  if (currentTime >= 24) currentTime -= 24;

function draw() {
  currentTime += CYCLE_SPEED;
  if (currentTime >= 24) currentTime -= 24;

  let skyColor;
  let currentHour = floor(currentTime);
  let phase = getPhase(currentTime);

  if (phase === 'day') {
    skyColor = color(135, 206, 235);
  } else if (phase === 'dusk') {
    skyColor = lerpColor(color(135, 206, 235), color(255, 140, 0), (currentTime - 18) / 2);
  } else if (phase === 'night') {
    skyColor = color(25, 25, 112);
  } else if (phase === 'dawn') {
    skyColor = lerpColor(color(25, 25, 112), color(135, 206, 235), (currentTime - 4) / 2);
  }
  background(skyColor);

  handleInput();
  updatePlayer();
  updateZombies();
  updateCamera();

  drawWorld();
  for (let p of players) {
    drawPlayer(p);
  }
  for (let z of zombies) {
    drawZombie(z);
  }

  drawCursorHighlight();
  if (isTouchDevice) {
    drawTouchControls();
  }
  drawUI();

  if (phase === 'night' && zombies.length < MAX_ZOMBIES && random() < ZOMBIE_SPAWN_CHANCE) {
    spawnZombie();
  }
}

Line-by-line explanation (17 lines)

🔧 Subcomponents:

calculation Day/Night Cycle Update currentTime += CYCLE_SPEED;

Advances time each frame and wraps the hour back to 0 after 24, creating a continuous day/night loop.

conditional Sky Color Selection if (phase === 'day') { skyColor = color(135, 206, 235); }

Determines which sky color to use based on the current phase (day, dusk, night, or dawn), with smooth transitions between phases using lerpColor().

conditional Zombie Night Spawn if (phase === 'night' && zombies.length < MAX_ZOMBIES && random() < ZOMBIE_SPAWN_CHANCE) { spawnZombie(); }

Spawns a new zombie during night phases if the population hasn't reached the maximum and the random chance triggers.

currentTime += CYCLE_SPEED;: Increments the game's hour counter by a small amount each frame, making time pass at the rate defined by CYCLE_SPEED.
if (currentTime >= 24) currentTime -= 24;: Wraps time back to 0 when it reaches 24 hours, creating a continuous repeating cycle.
let phase = getPhase(currentTime);: Calls a helper function to determine the current phase of day (day, dusk, night, or dawn) based on the current hour.
if (phase === 'day') { skyColor = color(135, 206, 235); }: Sets the sky to bright blue during the day phase.
skyColor = lerpColor(color(135, 206, 235), color(255, 140, 0), (currentTime - 18) / 2);: During dusk, smoothly interpolates between blue sky and orange horizon—lerpColor() blends two colors based on a 0-1 ratio.
background(skyColor);: Clears the entire canvas with the current sky color, erasing the previous frame.
handleInput();: Reads keyboard and touch input to update each player's horizontal velocity and jump state.
updatePlayer();: Applies gravity and collision detection to both players, updating their positions and velocities.
updateZombies();: Updates zombie physics and AI behavior—each zombie moves toward the nearest player.
updateCamera();: Moves the camera to center on the midpoint between both players, ensuring both are always visible.
drawWorld();: Renders all visible tiles in the world grid, culled to only draw blocks on screen.
for (let p of players) { drawPlayer(p); }: Loops through all players and draws each one as a simple colored rectangle.
for (let z of zombies) { drawZombie(z); }: Loops through all zombies and draws each as a green rectangle with eyes.
drawCursorHighlight();: Draws a yellow outline around the tile that the mouse is currently hovering over (for Player 1).
if (isTouchDevice) { drawTouchControls(); }: On mobile devices, renders left, right, and jump buttons at the bottom of the screen.
drawUI();: Renders the hotbars for both players and the instructions panel.
if (phase === 'night' && zombies.length < MAX_ZOMBIES && random() < ZOMBIE_SPAWN_CHANCE) { spawnZombie(); }: During night, has a small random chance each frame to spawn a new zombie (up to the max limit).

`initWorld()`

initWorld() is the first major function called in setup(). It builds the entire world data structure and spawns both players. Procedural generation—using noise() to create terrain variation—is a powerful technique used in real games to create large, varied worlds without manually placing every block.

🔬 The distance threshold 2.6 controls the leaf canopy shape. What happens if you change it to 3.5? To 1.5? Does the tree look rounder or pointier?

      for (let lx = -2; lx <= 2; lx++) {
        for (let ly = -2; ly <= 1; ly++) {
          const tx = x + lx;
          const ty = leafY + ly;
          if (tx >= 0 && tx < WORLD_WIDTH && ty >= 0 && ty < WORLD_HEIGHT) {
            if (dist(lx, ly, 0, 0) < 2.6 && world[tx][ty] === AIR) {
              world[tx][ty] = LEAVES;
            }
          }
        }
      }

function initWorld() {
  world = new Array(WORLD_WIDTH);
  for (let x = 0; x < WORLD_WIDTH; x++) {
    world[x] = new Array(WORLD_HEIGHT).fill(AIR);
  }

  const baseHeight = 30;
  for (let x = 0; x < WORLD_WIDTH; x++) {
    let h = floor(noise(x * 0.12) * 10) + baseHeight;
    h = constrain(h, 12, WORLD_HEIGHT - 6);

    for (let y = h; y < WORLD_HEIGHT; y++) {
      world[x][y] = STONE;
    }

    if (h - 1 >= 0) world[x][h - 1] = GRASS;
    if (h - 2 >= 0) world[x][h - 2] = DIRT;
    if (h - 3 >= 0) world[x][h - 3] = DIRT;

    if (random() < 0.08 && h - 4 > 0) {
      const trunkHeight = 4;
      for (let t = 0; t < trunkHeight; t++) {
        const ty = h - 2 - t;
        if (ty >= 0) world[x][ty] = WOOD;
      }

      const leafY = h - 2 - trunkHeight;
      for (let lx = -2; lx <= 2; lx++) {
        for (let ly = -2; ly <= 1; ly++) {
          const tx = x + lx;
          const ty = leafY + ly;
          if (tx >= 0 && tx < WORLD_WIDTH && ty >= 0 && ty < WORLD_HEIGHT) {
            if (dist(lx, ly, 0, 0) < 2.6 && world[tx][ty] === AIR) {
              world[tx][ty] = LEAVES;
            }
          }
        }
      }
    }
  }

  const spawnX1 = floor(WORLD_WIDTH / 2);
  let spawnY1 = 0;
  for (let y = 0; y < WORLD_HEIGHT; y++) {
    if (world[spawnX1][y] !== AIR) {
      spawnY1 = y - 1;
      break;
    }
  }

  const spawnX2 = spawnX1 + 2;
  let spawnY2 = 0;
  for (let y = 0; y < WORLD_HEIGHT; y++) {
    if (world[spawnX2][y] !== AIR) {
      spawnY2 = y - 1;
      break;
    }
  }

  players = [
    {
      x: spawnX1 * TILE_SIZE,
      y: spawnY1 * TILE_SIZE - PLAYER_HEIGHT,
      w: PLAYER_WIDTH,
      h: PLAYER_HEIGHT,
      vx: 0,
      vy: 0,
      onGround: false,
      inventory: player1Inventory,
      selectedIndex: 0,
      controls: PLAYER_CONTROLS[0],
      colorBody: PLAYER_CONTROLS[0].colorBody,
      colorPants: PLAYER_CONTROLS[0].colorPants
    },
    {
      x: spawnX2 * TILE_SIZE,
      y: spawnY2 * TILE_SIZE - PLAYER_HEIGHT,
      w: PLAYER_WIDTH,
      h: PLAYER_HEIGHT,
      vx: 0,
      vy: 0,
      onGround: false,
      inventory: player2Inventory,
      selectedIndex: 0,
      controls: PLAYER_CONTROLS[1],
      colorBody: PLAYER_CONTROLS[1].colorBody,
      colorPants: PLAYER_CONTROLS[1].colorPants
    }
  ];
}

Line-by-line explanation (16 lines)

🔧 Subcomponents:

for-loop World Grid Initialization for (let x = 0; x < WORLD_WIDTH; x++) { world[x] = new Array(WORLD_HEIGHT).fill(AIR); }

Creates a 2D array representing the world grid, where each cell can hold a block ID; all cells start as AIR (empty).

calculation Perlin Noise Terrain Height let h = floor(noise(x * 0.12) * 10) + baseHeight;

Uses Perlin noise to generate terrain height variation—noise(x * 0.12) produces smooth, natural-looking hills across the world width.

conditional Random Tree Placement if (random() < 0.08 && h - 4 > 0) {

8% chance per column to spawn a tree; checks that there's enough vertical space above the terrain.

for-loop Leaf Canopy Generation for (let lx = -2; lx <= 2; lx++) { for (let ly = -2; ly <= 1; ly++) {

Loops through a 5x4 area around the tree top and places leaves in a circular pattern using distance math.

for-loop Player Spawn Height Detection for (let y = 0; y < WORLD_HEIGHT; y++) { if (world[spawnX1][y] !== AIR) { spawnY1 = y - 1; break; } }

Finds the first solid block below the spawn X position and places the player on top of it.

world = new Array(WORLD_WIDTH);: Creates an empty array with length WORLD_WIDTH (200) to hold columns of the world.
for (let x = 0; x < WORLD_WIDTH; x++) { world[x] = new Array(WORLD_HEIGHT).fill(AIR); }: For each column x, creates a vertical array of height WORLD_HEIGHT and fills it all with AIR block IDs.
let h = floor(noise(x * 0.12) * 10) + baseHeight;: Uses Perlin noise to generate the terrain height at column x. Multiplying x by 0.12 controls the 'frequency' of hills, and adding baseHeight (30) sets the average height.
h = constrain(h, 12, WORLD_HEIGHT - 6);: Clamps the terrain height between 12 and 54 so mountains never reach the top or bottom of the world.
for (let y = h; y < WORLD_HEIGHT; y++) { world[x][y] = STONE; }: Fills all blocks from the terrain height down to the bottom with stone, creating a solid underground.
if (h - 1 >= 0) world[x][h - 1] = GRASS;: Places a grass block on the surface of the terrain (one row above the stone).
if (h - 2 >= 0) world[x][h - 2] = DIRT;: Places two rows of dirt just below the grass surface for realistic layering.
if (random() < 0.08 && h - 4 > 0) {: Has an 8% chance to spawn a tree at this column, but only if there's at least 4 rows of vertical space.
for (let t = 0; t < trunkHeight; t++) { const ty = h - 2 - t; if (ty >= 0) world[x][ty] = WOOD; }: Stacks 4 wood blocks vertically to create the tree trunk, starting 2 rows above the terrain surface.
const leafY = h - 2 - trunkHeight;: Calculates the Y position of the tree canopy, which is at the top of the trunk.
for (let lx = -2; lx <= 2; lx++) { for (let ly = -2; ly <= 1; ly++) {: Loops through a 5-wide and 4-tall rectangular region centered on the canopy.
if (dist(lx, ly, 0, 0) < 2.6 && world[tx][ty] === AIR) { world[tx][ty] = LEAVES; }: Uses dist() to measure how far each cell is from the canopy center, placing leaves only if distance < 2.6 (creating a circular canopy) and the cell is currently air.
const spawnX1 = floor(WORLD_WIDTH / 2);: Sets Player 1's spawn X position to the middle of the world.
for (let y = 0; y < WORLD_HEIGHT; y++) { if (world[spawnX1][y] !== AIR) { spawnY1 = y - 1; break; } }: Scans downward from the top until it finds the first solid block, then places the player one row above it (so they stand on the surface).
const spawnX2 = spawnX1 + 2;: Places Player 2 two tiles to the right of Player 1 so they start near each other.
players = [ { ... }, { ... } ];: Creates an array containing both player objects with all their initial properties (position, velocity, inventory, controls, colors).

`handleInput()`

handleInput() runs every frame and translates player key presses into velocity changes. By resetting vx to 0 each frame and then conditionally setting it based on key state, the code creates responsive, snappy movement that stops immediately when keys are released.

function handleInput() {
  for (let i = 0; i < players.length; i++) {
    let p = players[i];
    p.vx = 0;

    if (keyIsDown(p.controls.left) || (i === 0 && touchControls.left)) {
      p.vx = -MOVE_SPEED;
    }
    if (keyIsDown(p.controls.right) || (i === 0 && touchControls.right)) {
      p.vx = MOVE_SPEED;
    }

    if (
      (keyIsDown(p.controls.jump) || (i === 0 && touchControls.jump)) &&
      p.onGround
    ) {
      p.vy = -JUMP_SPEED;
      p.onGround = false;
      playJumpSound();
      if (i === 0) touchControls.jump = false;
    }
  }
}

Line-by-line explanation (10 lines)

🔧 Subcomponents:

for-loop Per-Player Input Processing for (let i = 0; i < players.length; i++) {

Iterates through both players, handling movement for each independently using their own control schemes.

conditional Horizontal Movement Input if (keyIsDown(p.controls.left) || (i === 0 && touchControls.left)) { p.vx = -MOVE_SPEED; }

Checks both keyboard and touch input for left movement, applying negative velocity if pressed.

conditional Jump Condition Check if ( (keyIsDown(p.controls.jump) || (i === 0 && touchControls.jump)) && p.onGround ) {

Only allows jumping when the player is on the ground (not mid-air), prevents infinite air jumps.

for (let i = 0; i < players.length; i++) {: Loops through both players (index 0 and 1) to handle their input separately.
let p = players[i];: Creates a shorthand reference to the current player object.
p.vx = 0;: Resets horizontal velocity to 0 each frame—this makes movement feel responsive and stops sliding when keys are released.
if (keyIsDown(p.controls.left) || (i === 0 && touchControls.left)) { p.vx = -MOVE_SPEED; }: Checks if the player's left movement key is held down OR if Player 1 is using the left touch button; if so, sets horizontal velocity to negative (leftward).
if (keyIsDown(p.controls.right) || (i === 0 && touchControls.right)) { p.vx = MOVE_SPEED; }: Checks if the player's right movement key is held down; if so, sets horizontal velocity to positive (rightward).
if ( (keyIsDown(p.controls.jump) || (i === 0 && touchControls.jump)) && p.onGround ) {: Only allows jump input if both conditions are true: (1) jump key is pressed AND (2) the player is standing on ground (not already in mid-air).
p.vy = -JUMP_SPEED;: Sets vertical velocity to a negative value, which will make gravity pull downward and create an upward arc.
p.onGround = false;: Marks the player as no longer on ground, preventing another jump until they land again.
playJumpSound();: Triggers a jump sound effect.
if (i === 0) touchControls.jump = false;: For Player 1 (touch device), immediately resets the jump button so it only triggers once per tap.

`updatePlayerPhysics()`

updatePlayerPhysics() is the heart of the game engine. It applies gravity, moves the player in both axes, and detects collisions by converting the player's bounding box to tile coordinates and checking which blocks they overlap. This tile-based collision detection is much simpler than pixel-perfect collisions and is perfect for grid-based games like Minecraft.

🔬 Gravity pulls the player down each frame, and the cap prevents infinite acceleration. What happens if you remove the cap line? Can you feel the difference in how heavy the player becomes after falling for a while?

  p.vy += GRAVITY;
  p.vy = min(p.vy, 18);

function updatePlayerPhysics(p) {
  p.vy += GRAVITY;
  p.vy = min(p.vy, 18);
  p.onGround = false;

  let newX = p.x + p.vx;
  newX = constrain(newX, 0, WORLD_WIDTH * TILE_SIZE - p.w);

  if (p.vx > 0) {
    const right = newX + p.w;
    const top = p.y;
    const bottom = p.y + p.h - 1;
    const tileRight = floor(right / TILE_SIZE);
    for (let ty = floor(top / TILE_SIZE); ty <= floor(bottom / TILE_SIZE); ty++) {
      if (isSolidTile(tileRight, ty)) {
        newX = tileRight * TILE_SIZE - p.w;
        p.vx = 0;
        break;
      }
    }
  } else if (p.vx < 0) {
    const left = newX;
    const top = p.y;
    const bottom = p.y + p.h - 1;
    const tileLeft = floor(left / TILE_SIZE);
    for (let ty = floor(top / TILE_SIZE); ty <= floor(bottom / TILE_SIZE); ty++) {
      if (isSolidTile(tileLeft, ty)) {
        newX = (tileLeft + 1) * TILE_SIZE;
        p.vx = 0;
        break;
      }
    }
  }
  p.x = newX;

  let newY = p.y + p.vy;

  if (p.vy > 0) {
    let bottom = newY + p.h;
    if (bottom >= WORLD_HEIGHT * TILE_SIZE) {
      newY = WORLD_HEIGHT * TILE_SIZE - p.h;
      p.vy = 0;
      p.onGround = true;
    } else {
      const left = p.x;
      const right = p.x + p.w - 1;
      const tileBottom = floor(bottom / TILE_SIZE);
      for (let tx = floor(left / TILE_SIZE); tx <= floor(right / TILE_SIZE); tx++) {
        if (isSolidTile(tx, tileBottom)) {
          newY = tileBottom * TILE_SIZE - p.h;
          p.vy = 0;
          p.onGround = true;
          break;
        }
      }
    }
  } else if (p.vy < 0) {
    let top = newY;
    if (top <= 0) {
      newY = 0;
      p.vy = 0;
    } else {
      const left = p.x;
      const right = p.x + p.w - 1;
      const tileTop = floor(top / TILE_SIZE);
      for (let tx = floor(left / TILE_SIZE); tx <= floor(right / TILE_SIZE); tx++) {
        if (isSolidTile(tx, tileTop)) {
          newY = (tileTop + 1) * TILE_SIZE;
          p.vy = 0;
          break;
        }
      }
    }
  }

  p.y = newY;
}

Line-by-line explanation (21 lines)

🔧 Subcomponents:

calculation Gravity Acceleration p.vy += GRAVITY;

Adds gravitational acceleration to vertical velocity each frame, making players fall faster the longer they're in the air.

conditional Horizontal Collision Detection if (p.vx > 0) { ... } else if (p.vx < 0) { ... }

Checks for collisions with solid blocks in the direction of horizontal movement (right or left), adjusting position and stopping velocity if blocked.

conditional Vertical Collision Detection if (p.vy > 0) { ... } else if (p.vy < 0) { ... }

Checks for collisions with solid blocks during downward or upward movement, setting onGround when landing on a surface.

p.vy += GRAVITY;: Increases downward velocity by a constant gravity amount, simulating continuous acceleration downward.
p.vy = min(p.vy, 18);: Caps maximum falling speed at 18 pixels per frame so falling doesn't accelerate indefinitely.
p.onGround = false;: Assumes the player is airborne at the start of each physics update; it will be set back to true if we detect ground contact.
let newX = p.x + p.vx;: Calculates the new X position by adding horizontal velocity to the current position.
newX = constrain(newX, 0, WORLD_WIDTH * TILE_SIZE - p.w);: Prevents the player from moving outside the world boundaries (left and right edges).
if (p.vx > 0) {: This section handles collision detection when moving RIGHT. We check the right edge of the player against tiles.
const right = newX + p.w;: Calculates the x-coordinate of the player's right edge.
const tileRight = floor(right / TILE_SIZE);: Converts the right edge position to tile coordinates by dividing by TILE_SIZE and flooring.
for (let ty = floor(top / TILE_SIZE); ty <= floor(bottom / TILE_SIZE); ty++) {: Loops through all tiles from the player's top to bottom edge at this column, checking for collisions.
if (isSolidTile(tileRight, ty)) {: If a solid tile is found, the player hits it and cannot move further right.
newX = tileRight * TILE_SIZE - p.w;: Repositions the player so their right edge aligns with the left edge of the solid tile.
p.vx = 0;: Stops horizontal velocity so the player doesn't slide through the wall.
let newY = p.y + p.vy;: Calculates the new Y position by adding vertical velocity.
if (p.vy > 0) {: This section handles collision detection when moving DOWN (falling or jumping down).
let bottom = newY + p.h;: Calculates the Y-coordinate of the player's bottom edge.
if (bottom >= WORLD_HEIGHT * TILE_SIZE) {: Checks if the player has reached the absolute bottom of the world (invisible floor).
newY = WORLD_HEIGHT * TILE_SIZE - p.h; p.vy = 0; p.onGround = true;: Locks the player at the world bottom, stops vertical velocity, and marks them as on ground.
const tileBottom = floor(bottom / TILE_SIZE);: Converts the player's bottom edge position to a tile y-coordinate.
for (let tx = floor(left / TILE_SIZE); tx <= floor(right / TILE_SIZE); tx++) {: Loops through all tiles below the player's left-to-right span, checking for ground contact.
if (isSolidTile(tx, tileBottom)) {: If a solid tile is found below, the player is standing on it.
newY = tileBottom * TILE_SIZE - p.h; p.vy = 0; p.onGround = true;: Repositions the player on top of the tile, stops vertical motion, and marks them as grounded.

`updateCamera()`

updateCamera() implements split-screen awareness: instead of following a single player, it centers on the point between them. This is a foundational technique for cooperative games—it keeps both players visible as long as they stay reasonably close. The constrain() calls are critical: without them, the camera would drift into black space at world edges.

function updateCamera() {
  let midX = (players[0].x + players[1].x) / 2 + players[0].w / 2;
  let midY = (players[0].y + players[1].y) / 2 + players[0].h / 2;

  let targetX = midX - width / 2;
  const maxCamX = max(0, WORLD_WIDTH * TILE_SIZE - width);
  cameraX = constrain(targetX, 0, maxCamX);

  let targetY = midY - height / 2;
  const maxCamY = max(0, WORLD_HEIGHT * TILE_SIZE - height);
  cameraY = constrain(targetY, 0, maxCamY);
}

Line-by-line explanation (7 lines)

🔧 Subcomponents:

calculation Player Midpoint Calculation let midX = (players[0].x + players[1].x) / 2 + players[0].w / 2;

Calculates the center point between both players, which becomes the camera focus point.

calculation Camera Boundary Clamping cameraX = constrain(targetX, 0, maxCamX);

Ensures the camera never shows outside the world boundaries—clamping prevents rendering non-existent terrain.

let midX = (players[0].x + players[1].x) / 2 + players[0].w / 2;: Averages the X positions of both players and adds half the player width to get the true center point between them.
let midY = (players[0].y + players[1].y) / 2 + players[0].h / 2;: Averages the Y positions of both players to find the vertical center point.
let targetX = midX - width / 2;: Calculates the camera X position so that the midpoint appears at the center of the screen (midX - half the screen width).
const maxCamX = max(0, WORLD_WIDTH * TILE_SIZE - width);: Calculates the maximum valid camera X position so the camera shows the rightmost edge of the world without empty space.
cameraX = constrain(targetX, 0, maxCamX);: Clamps the camera X position between 0 (left edge) and maxCamX (right edge), preventing camera drift into empty space.
let targetY = midY - height / 2;: Calculates the target camera Y position to keep the midpoint vertically centered on screen.
cameraY = constrain(targetY, 0, maxCamY);: Clamps the camera Y position to prevent scrolling above the top or below the bottom of the world.

`drawWorld()`

drawWorld() is a textbook example of frustum culling—only rendering what's on-screen. This technique is essential for performance: rendering a 200x60 grid (12,000 tiles) would be slow, but rendering only the ~200 visible tiles per frame is instant. The switch statement for colors is a simple lookup table; real games often use tilemap texture atlases for much faster rendering.

🔬 Every block is drawn with fill() then rect(). What happens if you remove the rect() call? Do you see nothing drawn, or do the colors still appear somehow?

      const sx = x * TILE_SIZE - cameraX;
      const sy = y * TILE_SIZE - cameraY;

      switch (block) {
        case GRASS:  fill(95, 159, 53);      break;
        case DIRT:   fill(121, 85, 58);      break;
        case STONE:  fill(140);              break;
        case WOOD:   fill(102, 51, 0);       break;
        case LEAVES: fill(46, 139, 87, 230); break;
      }
      rect(sx, sy, TILE_SIZE, TILE_SIZE);

function drawWorld() {
  noStroke();

  let startCol = floor(cameraX / TILE_SIZE);
  let endCol = startCol + floor(width / TILE_SIZE) + 2;
  startCol = max(0, startCol);
  endCol = min(WORLD_WIDTH - 1, endCol);

  let startRow = floor(cameraY / TILE_SIZE);
  let endRow = startRow + floor(height / TILE_SIZE) + 2;
  startRow = max(0, startRow);
  endRow = min(WORLD_HEIGHT - 1, endRow);

  for (let x = startCol; x <= endCol; x++) {
    for (let y = startRow; y <= endRow; y++) {
      const block = world[x][y];
      if (block === AIR) continue;

      const sx = x * TILE_SIZE - cameraX;
      const sy = y * TILE_SIZE - cameraY;

      switch (block) {
        case GRASS:  fill(95, 159, 53);      break;
        case DIRT:   fill(121, 85, 58);      break;
        case STONE:  fill(140);              break;
        case WOOD:   fill(102, 51, 0);       break;
        case LEAVES: fill(46, 139, 87, 230); break;
      }
      rect(sx, sy, TILE_SIZE, TILE_SIZE);
    }
  }
}

Line-by-line explanation (11 lines)

🔧 Subcomponents:

calculation Horizontal Frustum Culling let startCol = floor(cameraX / TILE_SIZE); let endCol = startCol + floor(width / TILE_SIZE) + 2;

Calculates which columns of tiles are on-screen so we only draw visible blocks (major performance optimization for large worlds).

for-loop Tile Rendering Loop for (let x = startCol; x <= endCol; x++) { for (let y = startRow; y <= endRow; y++) {

Iterates only through visible tiles and renders each one with appropriate color based on block type.

switch-case Block Type Color Assignment switch (block) { case GRASS: fill(95, 159, 53); break; ... }

Assigns RGB colors to each block type so grass is green, dirt is brown, stone is gray, etc.

noStroke();: Removes outlines from rectangles so tiles render cleanly without borders between them.
let startCol = floor(cameraX / TILE_SIZE);: Converts the camera X position to a tile column index, which is the leftmost visible column.
let endCol = startCol + floor(width / TILE_SIZE) + 2;: Calculates the rightmost visible column by adding screen width (in tiles) to startCol, plus a small buffer for safety.
startCol = max(0, startCol); endCol = min(WORLD_WIDTH - 1, endCol);: Clamps the start and end columns to valid world bounds so we never try to render tiles outside the grid.
for (let x = startCol; x <= endCol; x++) { for (let y = startRow; y <= endRow; y++) {: Nested loop through all visible tiles, from left to right and top to bottom.
const block = world[x][y];: Retrieves the block ID at the current tile position.
if (block === AIR) continue;: Skips empty (air) tiles—we don't render them, saving drawing calls.
const sx = x * TILE_SIZE - cameraX;: Converts tile X position to screen X position by multiplying by tile size and subtracting the camera offset.
const sy = y * TILE_SIZE - cameraY;: Converts tile Y position to screen Y position, accounting for vertical camera offset.
switch (block) { case GRASS: fill(95, 159, 53); break; ... }: Uses a switch statement to assign a fill color based on block type, then immediately draws the tile.
rect(sx, sy, TILE_SIZE, TILE_SIZE);: Draws a square tile at the calculated screen position with the chosen color.

`spawnZombie()`

spawnZombie() is a robust spawn system that validates multiple conditions before placing an enemy. The attempt loop prevents infinite searches, the distance check keeps the game fair, and the block collision checks prevent zombies from spawning inside terrain. This multi-factor validation is crucial for game balance and prevents game-breaking bugs.

🔬 This code checks that zombies don't spawn too close to players. What happens if you change SAFE_SPAWN_DISTANCE to a very large number, like TILE_SIZE * 50? Can zombies spawn near the players now?

    let safe = true;
    for (let p of players) {
      if (dist(spawnX + ZOMBIE_WIDTH / 2, spawnY + ZOMBIE_HEIGHT / 2, p.x + p.w / 2, p.y + p.h / 2) < SAFE_SPAWN_DISTANCE) {
        safe = false;
        break;
      }
    }

function spawnZombie() {
  if (zombies.length >= MAX_ZOMBIES) return;

  let spawnX, spawnY;
  let attempts = 0;
  const maxAttempts = 100;

  while (attempts < maxAttempts) {
    spawnX = floor(random(WORLD_WIDTH)) * TILE_SIZE;
    spawnY = 0;

    for (let y = 0; y < WORLD_HEIGHT; y++) {
      if (isSolidTile(floor(spawnX / TILE_SIZE), y)) {
        spawnY = y * TILE_SIZE - ZOMBIE_HEIGHT;
        break;
      }
    }

    let safe = true;
    for (let p of players) {
      if (dist(spawnX + ZOMBIE_WIDTH / 2, spawnY + ZOMBIE_HEIGHT / 2, p.x + p.w / 2, p.y + p.h / 2) < SAFE_SPAWN_DISTANCE) {
        safe = false;
        break;
      }
    }

    if (isSolidTile(floor(spawnX / TILE_SIZE), floor(spawnY / TILE_SIZE)) ||
        isSolidTile(floor((spawnX + ZOMBIE_WIDTH - 1) / TILE_SIZE), floor(spawnY / TILE_SIZE)) ||
        isSolidTile(floor(spawnX / TILE_SIZE), floor((spawnY + ZOMBIE_HEIGHT - 1) / TILE_SIZE)) ||
        isSolidTile(floor((spawnX + ZOMBIE_WIDTH - 1) / TILE_SIZE), floor((spawnY + ZOMBIE_HEIGHT - 1) / TILE_SIZE))) {
      safe = false;
    }

    if (safe) {
      break;
    }
    attempts++;
  }

  if (attempts < maxAttempts) {
    zombies.push({
      x: spawnX,
      y: spawnY,
      w: ZOMBIE_WIDTH,
      h: ZOMBIE_HEIGHT,
      vx: 0,
      vy: 0,
      onGround: false,
      color: color(34, 139, 34)
    });
  }
}

Line-by-line explanation (13 lines)

🔧 Subcomponents:

while-loop Safe Spawn Position Search while (attempts < maxAttempts) {

Tries up to 100 random spawn positions to find one that is safe (not too close to players, not inside a block).

for-loop Ground Height Detection for (let y = 0; y < WORLD_HEIGHT; y++) { if (isSolidTile(floor(spawnX / TILE_SIZE), y)) {

Scans downward from the top to find the terrain surface where the zombie should stand.

conditional Spawn Safety Validation if (dist(...) < SAFE_SPAWN_DISTANCE) { safe = false; }

Checks that the spawn location is far enough from both players and not inside solid terrain blocks.

if (zombies.length >= MAX_ZOMBIES) return;: Early exit if we've already spawned the maximum number of zombies (10).
let attempts = 0; const maxAttempts = 100;: Sets up a counter to limit how many spawn position attempts we make (prevents infinite loops).
while (attempts < maxAttempts) {: Tries up to 100 random positions to find a valid spawn location.
spawnX = floor(random(WORLD_WIDTH)) * TILE_SIZE;: Picks a random column in the world and converts it to pixel coordinates.
spawnY = 0;: Starts the zombie at the top of the world; we'll scan downward to find ground.
for (let y = 0; y < WORLD_HEIGHT; y++) { if (isSolidTile(floor(spawnX / TILE_SIZE), y)) {: Scans downward column-by-column until it finds a solid block (the terrain).
spawnY = y * TILE_SIZE - ZOMBIE_HEIGHT;: Places the zombie on top of the first solid block found, just like player spawning.
let safe = true;: Assumes the spawn location is safe; we'll check multiple conditions and set it to false if any fail.
for (let p of players) { if (dist(spawnX + ZOMBIE_WIDTH / 2, spawnY + ZOMBIE_HEIGHT / 2, p.x + p.w / 2, p.y + p.h / 2) < SAFE_SPAWN_DISTANCE) {: Checks each player: if a zombie's center is closer than SAFE_SPAWN_DISTANCE (8 tiles) to any player's center, mark it as unsafe.
if (isSolidTile(floor(spawnX / TILE_SIZE), floor(spawnY / TILE_SIZE)) || ...): Checks all four corners of the zombie's bounding box to ensure it's not spawning inside a solid block.
if (safe) { break; }: If this position passes all safety checks, exit the while loop and use it.
attempts++;: Increment the attempt counter; if we reach 100 attempts without finding a safe spot, give up.
if (attempts < maxAttempts) { zombies.push({...}); }: Only actually create the zombie if we found a valid spawn position within our attempt limit.

`updateZombiePhysics()`

updateZombiePhysics() mirrors updatePlayerPhysics() but adds AI behavior at the start. The nearest-player search is a simple form of enemy AI: compute distance to each potential target and pick the closest one. This creates the illusion of intelligent behavior—zombies appear to 'hunt' players—but is actually just a distance comparison each frame.

🔬 This code finds the closest player. What happens if you change it to ALWAYS target players[0] (ignoring Player 2)? Do zombies only chase one player now?

  let nearestPlayer = null;
  let minDist = Infinity;
  for (let p of players) {
    let d = dist(z.x, z.y, p.x, p.y);
    if (d < minDist) {
      minDist = d;
      nearestPlayer = p;
    }
  }

function updateZombiePhysics(z) {
  z.vy += GRAVITY;
  z.vy = min(z.vy, 18);
  z.onGround = false;

  let nearestPlayer = null;
  let minDist = Infinity;
  for (let p of players) {
    let d = dist(z.x, z.y, p.x, p.y);
    if (d < minDist) {
      minDist = d;
      nearestPlayer = p;
    }
  }

  if (nearestPlayer) {
    if (z.x < nearestPlayer.x) z.vx = ZOMBIE_MOVE_SPEED;
    else z.vx = -ZOMBIE_MOVE_SPEED;
  } else {
    z.vx = 0;
  }

  // Horizontal movement + collisions (similar to player)
  let newX = z.x + z.vx;
  newX = constrain(newX, 0, WORLD_WIDTH * TILE_SIZE - z.w);

  if (z.vx > 0) {
    const right = newX + z.w;
    const top = z.y;
    const bottom = z.y + z.h - 1;
    const tileRight = floor(right / TILE_SIZE);
    for (let ty = floor(top / TILE_SIZE); ty <= floor(bottom / TILE_SIZE); ty++) {
      if (isSolidTile(tileRight, ty)) {
        newX = tileRight * TILE_SIZE - z.w;
        z.vx = 0;
        break;
      }
    }
  } else if (z.vx < 0) {
    const left = newX;
    const top = z.y;
    const bottom = z.y + z.h - 1;
    const tileLeft = floor(left / TILE_SIZE);
    for (let ty = floor(top / TILE_SIZE); ty <= floor(bottom / TILE_SIZE); ty++) {
      if (isSolidTile(tileLeft, ty)) {
        newX = (tileLeft + 1) * TILE_SIZE;
        z.vx = 0;
        break;
      }
    }
  }
  z.x = newX;

  let newY = z.y + z.vy;

  if (z.vy > 0) {
    let bottom = newY + z.h;
    if (bottom >= WORLD_HEIGHT * TILE_SIZE) {
      newY = WORLD_HEIGHT * TILE_SIZE - z.h;
      z.vy = 0;
      z.onGround = true;
    } else {
      const left = z.x;
      const right = z.x + z.w - 1;
      const tileBottom = floor(bottom / TILE_SIZE);
      for (let tx = floor(left / TILE_SIZE); tx <= floor(right / TILE_SIZE); tx++) {
        if (isSolidTile(tx, tileBottom)) {
          newY = tileBottom * TILE_SIZE - z.h;
          z.vy = 0;
          z.onGround = true;
          break;
        }
      }
    }
  } else if (z.vy < 0) {
    let top = newY;
    if (top <= 0) {
      newY = 0;
      z.vy = 0;
    } else {
      const left = z.x;
      const right = z.x + z.w - 1;
      const tileTop = floor(top / TILE_SIZE);
      for (let tx = floor(left / TILE_SIZE); tx <= floor(right / TILE_SIZE); tx++) {
        if (isSolidTile(tx, tileTop)) {
          newY = (tileTop + 1) * TILE_SIZE;
          z.vy = 0;
          break;
        }
      }
    }
  }

  z.y = newY;
}

Line-by-line explanation (8 lines)

🔧 Subcomponents:

for-loop Nearest Player Detection for (let p of players) { let d = dist(z.x, z.y, p.x, p.y); if (d < minDist) { minDist = d; nearestPlayer = p; } }

Finds which player is closest to the zombie using distance calculations.

conditional AI Chasing Logic if (z.x < nearestPlayer.x) z.vx = ZOMBIE_MOVE_SPEED;

Sets zombie horizontal velocity toward the nearest player: right if player is to the right, left if to the left.

z.vy += GRAVITY;: Zombies fall due to gravity, just like players.
z.vy = min(z.vy, 18);: Caps falling speed at 18 pixels per frame.
let nearestPlayer = null; let minDist = Infinity;: Initializes variables to find the closest player (starting with infinite distance).
for (let p of players) { let d = dist(z.x, z.y, p.x, p.y);: Loops through all players and calculates Euclidean distance from the zombie to each one.
if (d < minDist) { minDist = d; nearestPlayer = p; }: Updates nearestPlayer and minDist whenever a player closer than the current minimum is found.
if (nearestPlayer) { if (z.x < nearestPlayer.x) z.vx = ZOMBIE_MOVE_SPEED;: If a player exists, sets zombie horizontal velocity to chase them: rightward if player is to the right.
else z.vx = -ZOMBIE_MOVE_SPEED;: Sets velocity leftward if the player is to the left of the zombie.
} else { z.vx = 0; }: If no players exist (shouldn't happen), stop horizontal movement.

`handleBlockInteraction()`

handleBlockInteraction() is the core of the sandbox mechanic. It converts screen/world coordinates, manages block state changes, and validates that placements don't create impossible geometry (blocks inside players). The coordinate conversion is subtle but critical: adding cameraX/Y before dividing by TILE_SIZE correctly maps the camera-offset screen coordinates back to world space.

function handleBlockInteraction(px, py, playerObj) {
  const tileX = floor((px + cameraX) / TILE_SIZE);
  const tileY = floor((py + cameraY) / TILE_SIZE);
  if (!isInWorld(tileX, tileY)) return;

  if (world[tileX][tileY] !== AIR) {
    world[tileX][tileY] = AIR;
    playBlockBreakSound();
  } else {
    const blockId = playerObj.inventory[playerObj.selectedIndex];
    if (blockId !== AIR) {
      const bx = tileX * TILE_SIZE;
      const by = tileY * TILE_SIZE;
      let overlapsAnyEntity = false;
      for (let p of players) {
        if (rectsOverlap(bx, by, TILE_SIZE, TILE_SIZE, p.x, p.y, p.w, p.h)) {
          overlapsAnyEntity = true;
          break;
        }
      }
      if (!overlapsAnyEntity) {
        for (let z of zombies) {
          if (rectsOverlap(bx, by, TILE_SIZE, TILE_SIZE, z.x, z.y, z.w, z.h)) {
            overlapsAnyEntity = true;
            break;
          }
        }
      }

      if (!overlapsAnyEntity) {
        world[tileX][tileY] = blockId;
        playBlockPlaceSound();
      }
    }
  }
}

Line-by-line explanation (11 lines)

🔧 Subcomponents:

calculation Screen to World Coordinate Conversion const tileX = floor((px + cameraX) / TILE_SIZE);

Converts a screen click position (px) to a world tile coordinate, accounting for camera offset.

conditional Block Breaking Logic if (world[tileX][tileY] !== AIR) { world[tileX][tileY] = AIR; playBlockBreakSound(); }

If the target tile has a block, removes it and plays a sound effect.

for-loop Player and Zombie Collision Check for (let p of players) { if (rectsOverlap(bx, by, TILE_SIZE, TILE_SIZE, p.x, p.y, p.w, p.h)) {

Prevents placing blocks inside players or zombies by checking overlap with all entities.

const tileX = floor((px + cameraX) / TILE_SIZE);: Converts screen X (px) to world tile X by adding the camera offset and dividing by tile size.
const tileY = floor((py + cameraY) / TILE_SIZE);: Converts screen Y (py) to world tile Y, accounting for vertical camera offset.
if (!isInWorld(tileX, tileY)) return;: Early exit if the click is outside world bounds (prevents accessing invalid array indices).
if (world[tileX][tileY] !== AIR) {: Checks if the target tile contains a block (anything other than AIR).
world[tileX][tileY] = AIR;: Removes the block by setting the tile to AIR.
playBlockBreakSound();: Plays a satisfying break sound effect.
const blockId = playerObj.inventory[playerObj.selectedIndex];: Retrieves the block type the player has currently selected in their hotbar.
if (blockId !== AIR) {: Only places a block if the selected inventory item is not air (i.e., it's a real block).
let overlapsAnyEntity = false;: Flag to track if the placement location overlaps any player or zombie.
for (let p of players) { if (rectsOverlap(bx, by, TILE_SIZE, TILE_SIZE, p.x, p.y, p.w, p.h)) {: Checks if the block would overlap with any player's bounding box.
if (!overlapsAnyEntity) { world[tileX][tileY] = blockId; playBlockPlaceSound(); }: If no collision detected, places the block and plays a place sound.

📦 Key Variables

world array

A 2D array [x][y] holding block IDs (AIR, GRASS, DIRT, STONE, WOOD, or LEAVES) representing the entire terrain.

let world; // initialized in initWorld()

players array

An array of two player objects, each with position (x, y), velocity (vx, vy), inventory, and control settings.

let players = [playerObj1, playerObj2];

zombies array

An array of zombie objects spawned during nighttime, each with position, velocity, and AI state.

let zombies = [];

cameraX number

The horizontal camera offset in pixels, used to convert world coordinates to screen coordinates.

let cameraX = 0;

cameraY number

The vertical camera offset in pixels, allowing the camera to pan up and down to follow players.

let cameraY = 0;

currentTime number

A floating-point value from 0-24 representing the in-game hour, which controls day/night cycles and zombie spawning.

let currentTime = 0;

touchControls object

An object tracking the state of virtual touch buttons on mobile (left, right, jump booleans).

let touchControls = { left: false, right: false, jump: false };

TILE_SIZE number

The pixel width/height of each block tile; changing this scales the entire visual grid.

const TILE_SIZE = 32;

GRAVITY number

The acceleration applied to vertical velocity each frame, controlling how quickly entities fall.

const GRAVITY = 0.8;

MOVE_SPEED number

How many pixels per frame a player moves horizontally when holding movement keys.

const MOVE_SPEED = 3;

JUMP_SPEED number

The initial upward velocity applied when a player jumps.

const JUMP_SPEED = 12;

🔧 Potential Improvements (5)

Here are some ways this code could be enhanced:

BUG handleBlockInteraction() and updatePlayerPhysics()

Players can get stuck inside blocks at world edges or by rapid block placement. The collision detection only prevents overlap at the moment of placement, not continuous overlap.

💡 Add a continuous collision check in updatePlayerPhysics() after movement is applied. If a player overlaps a block, push them out in the direction they came from (or nearest safe direction).

PERFORMANCE updateZombies() and updateZombiePhysics()

Each zombie runs distance checks to all players every frame. With 10 zombies and 2 players, that's 20 distance calculations per frame. Spatial partitioning could be added for larger worlds.

💡 Cache the nearest player or use a spatial grid to avoid checking all zombies against all players every single frame. For this sketch's scale it's fine, but it doesn't scale to 100+ enemies.

STYLE PLAYER_CONTROLS array

Control key codes are hard-coded magic numbers (65 for A, 87 for W). A new player reading the code won't know which numbers map to which keys without looking up ASCII codes.

💡 Use p5.js KEY_CODES constants or add comments clarifying the key names: `left: 65, // A`, or better yet, use a key name lookup function if p5.js provides one.

FEATURE spawnZombie() and updateZombiePhysics()

Zombies use simple left/right chasing AI and have no jumping ability, making them easy to avoid by jumping over them or standing on high ground.

💡 Add simple zombie jump AI: if a zombie is on the ground and blocked by terrain while chasing a player, set vy to -8 to make it jump over obstacles. This creates more challenge and makes the game less trivial for skilled players.

BUG drawHotbar() hotbar scaling and touch click detection

The hotbar for Player 2 is scaled down (0.7x), but the touch click detection in handleHotbarClick() doesn't correctly account for this scaling in all cases. Tapping the P2 hotbar may register offset clicks.

💡 Test the scaling math in handleHotbarClick() more carefully, or cache the scaled dimensions as constants so they're consistent between drawing and hit detection.

🔄 Code Flow

Code flow showing setup, draw, initworld, handleinput, updateplayerphysics, updatecamera, drawworld, spawzzombie, updatezombiephysics, handleblockinteraction

💡 Click on function names in the diagram to jump to their code

graph TD start[Start] --> setup[setup] setup --> initworld[initWorld] initworld --> world_grid_init[world_grid_init] world_grid_init --> perlin_terrain_gen[perlin_terrain_gen] perlin_terrain_gen --> tree_generation[tree_generation] tree_generation --> leaf_placement[leaf_placement] initworld --> player_spawn[player_spawn] setup --> draw[draw loop] draw --> day_night_cycle[day_night_cycle] day_night_cycle --> sky_color_transition[sky_color_transition] draw --> handleinput[handleInput] handleinput --> player_loop[player_loop] player_loop --> horizontal_movement[horizontal_movement] horizontal_movement --> jump_check[jump_check] player_loop --> gravity_application[gravity_application] gravity_application --> horizontal_collision[horizontal_collision] horizontal_collision --> vertical_collision[vertical_collision] draw --> updateplayerphysics[updatePlayerPhysics] updateplayerphysics --> updatecamera[updateCamera] updatecamera --> midpoint_calculation[midpoint_calculation] midpoint_calculation --> camera_constraint[camera_constraint] draw --> drawworld[drawWorld] drawworld --> frustum_culling_horizontal[frustum_culling_horizontal] frustum_culling_horizontal --> tile_render_loop[tile_render_loop] tile_render_loop --> block_color_switch[block_color_switch] draw --> spawzzombie[spawnZombie] spawzzombie --> spawn_position_search[spawn_position_search] spawn_position_search --> safety_checks[safety_checks] spawzzombie --> updatezombiephysics[updateZombiePhysics] updatezombiephysics --> nearest_player_search[nearest_player_search] nearest_player_search --> ai_movement[ai_movement] click setup href "#fn-setup" click initworld href "#fn-initworld" click draw href "#fn-draw" click day_night_cycle href "#sub-day_night_cycle" click sky_color_transition href "#sub-sky_color_transition" click handleinput href "#fn-handleinput" click player_loop href "#sub-player_loop" click horizontal_movement href "#sub-horizontal_movement" click jump_check href "#sub-jump_check" click gravity_application href "#sub-gravity_application" click horizontal_collision href "#sub-horizontal_collision" click vertical_collision href "#sub-vertical_collision" click updateplayerphysics href "#fn-updateplayerphysics" click updatecamera href "#fn-updatecamera" click drawworld href "#fn-drawworld" click frustum_culling_horizontal href "#sub-frustum_culling_horizontal" click tile_render_loop href "#sub-tile_render_loop" click block_color_switch href "#sub-block_color_switch" click spawzzombie href "#fn-spawnzombie" click spawn_position_search href "#sub-spawn_position_search" click safety_checks href "#sub-safety_checks" click updatezombiephysics href "#fn-updatezombiephysics" click nearest_player_search href "#sub-nearest_player_search" click ai_movement href "#sub-ai_movement" click world_grid_init href "#sub-world_grid_init" click perlin_terrain_gen href "#sub-perlin_terrain_gen" click tree_generation href "#sub-tree_generation" click leaf_placement href "#sub-leaf_placement" click player_spawn href "#sub-player_spawn"

❓ Frequently Asked Questions

What visual experience does the Simple MineCraft Cline (Remix) sketch offer?

The sketch creates a vibrant, side-scrolling 2D world inspired by Minecraft, featuring colorful landscapes and block-based terrain.

How can users interact with the Simple MineCraft Cline (Remix) sketch?

Users can run, jump, break, and place blocks using keyboard controls, allowing for solo play or cooperative gameplay with a friend on the same keyboard.

What creative coding concepts are illustrated in the Simple MineCraft Cline (Remix) sketch?

This sketch demonstrates tile-based world generation, simple physics for player movement, and interactive block manipulation, showcasing fundamental game development techniques.

Preview

Code flow diagram showing the structure of Simple MineCraft Cline (Remix) - Code flow showing setup, draw, initworld, handleinput, updateplayerphysics, updatecamera, drawworld, spawzzombie, updatezombiephysics, handleblockinteraction — Code Flow Diagram

🧪 Try This!

📖 About This Sketch

⚙️ How It Works

🎓 Concepts You'll Learn

📝 Code Breakdown

🔧 Subcomponents:

🔧 Subcomponents:

🔧 Subcomponents:

🔧 Subcomponents:

🔧 Subcomponents:

🔧 Subcomponents:

🔧 Subcomponents:

🔧 Subcomponents:

🔧 Subcomponents:

📦 Key Variables

🔧 Potential Improvements (5)

🔄 Code Flow

❓ Frequently Asked Questions

Explore More

Simple MineCraft Cline

Simple MineCraft Cline (Remix) (Remix)

Simple MineCraft Game (Louis)

Sketch 2026-06-08 16:23 (Remix) (Remix)

p5js.ai

Gallery

User Guide

Preview