engine.scope(({ start, cls, rectfill, pset, line, btn, caption, base }) => { const { KeySprite, ExitSprite, Darken, Constants, Levels } = base(); let currentLevel = 0; let map, wallTexture, px, py, pa; let keys, exitX, exitY, exitOpen; function loadLevel(index) { currentLevel = index; const level = Levels[currentLevel]; map = level.map; wallTexture = level.wallTexture; px = level.spawnX; py = level.spawnY; pa = 0; keys = level.keys.map(k => ({ x: k.x, y: k.y, collected: false })); exitX = level.exitX; exitY = level.exitY; exitOpen = false; } loadLevel(0); const sprites = { wall: wallTexture, key: KeySprite, exit: ExitSprite }; function update() { if (btn('ArrowLeft')) pa -= Constants.RotSpeed; if (btn('ArrowRight')) pa += Constants.RotSpeed; if (btn('ArrowUp')) { const nx = px + Math.cos(pa) * Constants.MoveSpeed; const ny = py + Math.sin(pa) * Constants.MoveSpeed; if (map[Math.floor(py)][Math.floor(nx)] === 0) px = nx; if (map[Math.floor(ny)][Math.floor(px)] === 0) py = ny; } if (btn('ArrowDown')) { const nx = px - Math.cos(pa) * Constants.MoveSpeed; const ny = py - Math.sin(pa) * Constants.MoveSpeed; if (map[Math.floor(py)][Math.floor(nx)] === 0) px = nx; if (map[Math.floor(ny)][Math.floor(px)] === 0) py = ny; } for (const k of keys) { if (k.collected) continue; const dx = px - k.x; const dy = py - k.y; if (Math.sqrt(dx * dx + dy * dy) < 0.5) { k.collected = true; } } const remaining = keys.filter(k => !k.collected).length; if (remaining === 0) exitOpen = true; if (exitOpen) { const dx = px - exitX; const dy = py - exitY; if (Math.sqrt(dx * dx + dy * dy) < 0.5) { const next = (currentLevel + 1) % Levels.length; loadLevel(next); sprites.wall = wallTexture; } } } function drawBillboard(spriteData, worldX, worldY, dirX, dirY, planeX, planeY, zBuffer) { const sx = worldX - px; const sy = worldY - py; const invDet = 1 / (planeX * dirY - dirX * planeY); const transformX = invDet * (dirY * sx - dirX * sy); const transformY = invDet * (-planeY * sx + planeX * sy); if (transformY <= 0) return; const screenX = Math.floor((128 / 2) * (1 + transformX / transformY)); const sprH = Math.floor(64 / transformY); const sprW = sprH; const drawStartY = Math.max(0, Math.floor(64 + 64 / transformY / 2 - sprH)); const drawEndY = Math.min(128, Math.floor(64 + 64 / transformY / 2)); const drawStartX = Math.max(0, Math.floor(screenX - sprW / 2)); const drawEndX = Math.min(128, Math.floor(screenX + sprW / 2)); for (let stripe = drawStartX; stripe < drawEndX; stripe++) { if (transformY >= zBuffer[stripe]) continue; const tx = Math.floor(((stripe - (screenX - sprW / 2)) * 8) / sprW); for (let y = drawStartY; y < drawEndY; y++) { const ty = Math.floor(((y - (drawStartY + sprH - (drawEndY - drawStartY))) * 8) / sprH); if (ty < 0 || ty > 7) continue; let color = spriteData[ty * 8 + tx]; if (color < 0) continue; if (transformY >= 6) { color = Darken[Darken[color]]; } else if (transformY >= 3) { color = Darken[color]; } pset(stripe, y, color); } } } function draw() { cls(0); rectfill(0, 0, 128, 64, 1); rectfill(0, 64, 128, 128, 5); const dirX = Math.cos(pa); const dirY = Math.sin(pa); const planeX = -dirY * Constants.Fov; const planeY = dirX * Constants.Fov; const zBuffer = new Array(128); for (let x = 0; x < 128; x++) { const cameraX = (2 * x) / 128 - 1; const rdx = dirX + planeX * cameraX; const rdy = dirY + planeY * cameraX; let mx = Math.floor(px); let my = Math.floor(py); const deltaDistX = Math.abs(rdx) < 1e-10 ? 1e30 : Math.abs(1 / rdx); const deltaDistY = Math.abs(rdy) < 1e-10 ? 1e30 : Math.abs(1 / rdy); let stepX, stepY, sideDistX, sideDistY; if (rdx < 0) { stepX = -1; sideDistX = (px - mx) * deltaDistX; } else { stepX = 1; sideDistX = (mx + 1 - px) * deltaDistX; } if (rdy < 0) { stepY = -1; sideDistY = (py - my) * deltaDistY; } else { stepY = 1; sideDistY = (my + 1 - py) * deltaDistY; } let side; while (true) { if (sideDistX < sideDistY) { sideDistX += deltaDistX; mx += stepX; side = 0; } else { sideDistY += deltaDistY; my += stepY; side = 1; } if (map[my]?.[mx] === 1) break; } const perpDist = side === 0 ? sideDistX - deltaDistX : sideDistY - deltaDistY; zBuffer[x] = perpDist; const stripeH = Math.floor(128 / perpDist); const drawStart = Math.max(0, Math.floor(64 - stripeH / 2)); const drawEnd = Math.min(128, Math.floor(64 + stripeH / 2)); let wallHit; if (side === 0) { wallHit = py + perpDist * rdy; } else { wallHit = px + perpDist * rdx; } wallHit -= Math.floor(wallHit); const tx = Math.floor(wallHit * 8); const texStep = 8 / stripeH; let texPos = (drawStart - 64 + stripeH / 2) * texStep; for (let sy = drawStart; sy < drawEnd; sy++) { const ty = Math.min(7, Math.floor(texPos)); texPos += texStep; let color = sprites.wall[ty * 8 + tx]; if (color < 0) continue; if (perpDist >= 6) { color = Darken[Darken[color]]; } else if (perpDist >= 3) { color = Darken[color]; } if (side === 0) { color = Darken[color]; } pset(x, sy, color); } } const billboards = []; for (const k of keys) { if (!k.collected) { billboards.push({ sprite: sprites.key, x: k.x, y: k.y }); } } if (exitOpen) { billboards.push({ sprite: sprites.exit, x: exitX, y: exitY }); } billboards .map(b => ({ b, dist: (b.x - px) * (b.x - px) + (b.y - py) * (b.y - py) })) .sort((a, b) => b.dist - a.dist) .forEach(({ b }) => drawBillboard(b.sprite, b.x, b.y, dirX, dirY, planeX, planeY, zBuffer)); for (let y = 0; y < Constants.MapSize; y++) { for (let x = 0; x < Constants.MapSize; x++) { const color = map[y][x] === 1 ? 5 : 6; rectfill( Constants.MmX + x * Constants.Cell, Constants.MmY + y * Constants.Cell, Constants.MmX + (x + 1) * Constants.Cell, Constants.MmY + (y + 1) * Constants.Cell, color, ); } } for (const k of keys) { if (k.collected) continue; pset( Constants.MmX + Math.floor(k.x * Constants.Cell), Constants.MmY + Math.floor(k.y * Constants.Cell), 10, ); } if (exitOpen) { pset( Constants.MmX + Math.floor(exitX * Constants.Cell), Constants.MmY + Math.floor(exitY * Constants.Cell), 11, ); } rectfill( Constants.MmX + Math.floor(px * Constants.Cell) - 1, Constants.MmY + Math.floor(py * Constants.Cell) - 1, Constants.MmX + Math.floor(px * Constants.Cell) + 2, Constants.MmY + Math.floor(py * Constants.Cell) + 2, 11, ); line( Constants.MmX + Math.floor(px * Constants.Cell), Constants.MmY + Math.floor(py * Constants.Cell), Constants.MmX + Math.floor(px * Constants.Cell + Math.cos(pa) * 4), Constants.MmY + Math.floor(py * Constants.Cell + Math.sin(pa) * 4), 11, ); const remaining = keys.filter(k => !k.collected).length; if (remaining > 0) { caption(remaining + ' keys left', 2, 2, 10); } else { caption('find the exit!', 2, 2, 11); } caption(Levels[currentLevel].name, 2, 10, 7); } start({ sprites, sounds: {}, update, draw, target }); });

Editing: Scene & Level Management: Collectible Keys

Recent Edits

Plugins