""" ════════════════════════════════════════════════════════════ MODULE 6 — Script 04: Spatial Audio & Dynamic Mixing ════════════════════════════════════════════════════════════ What this demonstrates: • Stereo panning based on position (spatial sound) • Distance-based volume attenuation • Dynamic mixing: layering sounds by game state • Sound cooldown to avoid overlap spam • pygame.mixer.Channel.set_volume(left, right) for stereo Controls: • Move mouse to change listener position • Click to spawn a sound source • SPACE: add ambient layer • ESC: quit ════════════════════════════════════════════════════════════ """ import pygame import sys import math import random import struct pygame.mixer.pre_init(44100, -16, 2, 1024) # stereo (2 channels) pygame.init() WIDTH, HEIGHT = 900, 600 FPS = 60 BLACK = (0, 0, 0) WHITE = (255, 255, 255) GRAY = (60, 60, 60) GRAY_LT = (150, 150, 150) BLUE = (50, 120, 220) GREEN = (50, 200, 100) RED = (220, 80, 70) YELLOW = (255, 220, 50) ORANGE = (255, 160, 30) DARK_BG = (10, 10, 20) screen = pygame.display.set_mode((WIDTH, HEIGHT)) pygame.display.set_caption("Module 6 — Spatial Audio") clock = pygame.time.Clock() F_SMALL = pygame.font.SysFont("monospace", 12) F_MED = pygame.font.SysFont("monospace", 15) F_LARGE = pygame.font.SysFont("monospace", 20, bold=True) def blit(surf, txt, pos, color=WHITE, font=None): surf.blit((font or F_MED).render(txt, True, color), pos) SAMPLE_RATE = 44100 def gen_stereo_samples(left_samples, right_samples): """Interleave L and R samples into stereo PCM bytes.""" n = min(len(left_samples), len(right_samples)) data = [] for i in range(n): l = max(-1.0, min(1.0, left_samples[i])) r = max(-1.0, min(1.0, right_samples[i])) data.append(int(l * 32767)) data.append(int(r * 32767)) return struct.pack(f"{len(data)}h", *data) def make_stereo_sound(freq, duration, vol=0.5): """Sine wave, identical L and R (panning done at runtime).""" n = int(SAMPLE_RATE * duration) mono = [vol * math.sin(2 * math.pi * freq * i / SAMPLE_RATE) * (1 - i / n) for i in range(n)] data = gen_stereo_samples(mono, mono) return pygame.mixer.Sound(buffer=data) def make_noise_stereo(duration, vol=0.3): n = int(SAMPLE_RATE * duration) mono = [vol * (random.random() * 2 - 1) * (1 - i / n) ** 2 for i in range(n)] data = gen_stereo_samples(mono, mono) return pygame.mixer.Sound(buffer=data) def make_ambient(freq, duration, vol=0.15): n = int(SAMPLE_RATE * duration) out = [] for i in range(n): t = i / SAMPLE_RATE env = 0.5 + 0.5 * math.sin(math.pi * i / n) out.append(vol * env * (math.sin(2*math.pi*freq*t) + 0.3*math.sin(2*math.pi*freq*1.5*t))) data = gen_stereo_samples(out, out) return pygame.mixer.Sound(buffer=data) print("Generating stereo audio...") pygame.mixer.set_num_channels(16) SOUNDS = { "ping": make_stereo_sound(440, 0.4), "low": make_stereo_sound(220, 0.5), "high": make_stereo_sound(880, 0.3), "noise": make_noise_stereo(0.3), "ambient": make_ambient(130, 2.0), } print("Ready.") MAX_DIST = 400.0 # Beyond this distance, sound is inaudible class SoundSource: """A point in the world that emits sound.""" COLOR_MAP = {"ping": YELLOW, "low": BLUE, "high": GREEN, "noise": RED} def __init__(self, x, y, kind): self.x = x self.y = y self.kind = kind self.color= self.COLOR_MAP.get(kind, WHITE) self.t = 0.0 self.channel = None self.alive = True def update_spatial(self, listener_x, listener_y, dt): self.t += dt dx = self.x - listener_x dy = self.y - listener_y dist = math.hypot(dx, dy) # Distance attenuation (linear falloff) vol = max(0.0, 1.0 - dist / MAX_DIST) # Stereo panning: normalize x position in screen pan = (self.x / WIDTH) * 2 - 1 # -1 (left) to +1 (right) left = vol * (1.0 - max(0, pan)) right = vol * (1.0 + min(0, pan)) left = max(0.0, min(1.0, left)) right = max(0.0, min(1.0, right)) if self.channel and self.channel.get_busy(): self.channel.set_volume(left, right) # Auto-remove after 3 seconds if self.t > 3.0: if self.channel: self.channel.stop() self.alive = False def play(self): sound = SOUNDS.get(self.kind, SOUNDS["ping"]) self.channel = sound.play(loops=2) if self.channel: self.channel.set_volume(0.5, 0.5) def draw(self, surface, listener_x, listener_y): if not self.alive: return dx = self.x - listener_x dy = self.y - listener_y dist = math.hypot(dx, dy) vol = max(0.0, 1.0 - dist / MAX_DIST) # Draw ripple rings rings = 3 for r in range(rings): phase = (self.t * 120 + r * 40) % 120 ring_r= int(phase * (1 + vol)) alpha = max(0, int(180 * (1 - phase / 120) * vol)) if ring_r > 0 and alpha > 0: ring_surf = pygame.Surface((ring_r*2+2, ring_r*2+2), pygame.SRCALPHA) pygame.draw.circle(ring_surf, (*self.color, alpha), (ring_r+1, ring_r+1), ring_r, 1) surface.blit(ring_surf, (int(self.x)-ring_r-1, int(self.y)-ring_r-1)) # Core dot pygame.draw.circle(surface, self.color, (int(self.x), int(self.y)), 8) pygame.draw.circle(surface, WHITE, (int(self.x), int(self.y)), 8, 1) # Volume bar above bar_w = int(vol * 60) pygame.draw.rect(surface, GRAY, (int(self.x)-30, int(self.y)-24, 60, 6)) pygame.draw.rect(surface, self.color, (int(self.x)-30, int(self.y)-24, bar_w, 6)) label = F_SMALL.render(f"{self.kind} {vol:.2f}", True, self.color) surface.blit(label, (int(self.x)-30, int(self.y)-38)) sources = [] ambient_channel= None t_global = 0.0 click_cooldown = 0.0 KINDS = ["ping", "low", "high", "noise"] kind_idx = 0 while True: dt = clock.tick(FPS) / 1000.0 t_global += dt click_cooldown = max(0, click_cooldown - dt) listener_x, listener_y = pygame.mouse.get_pos() for event in pygame.event.get(): if event.type == pygame.QUIT: pygame.quit(); sys.exit() if event.type == pygame.KEYDOWN: if event.key == pygame.K_ESCAPE: pygame.quit(); sys.exit() if event.key == pygame.K_SPACE: # Toggle ambient layer if ambient_channel and ambient_channel.get_busy(): ambient_channel.fadeout(500) ambient_channel = None else: ambient_channel = SOUNDS["ambient"].play(loops=-1) if ambient_channel: ambient_channel.set_volume(0.15, 0.15) if event.key == pygame.K_TAB: kind_idx = (kind_idx + 1) % len(KINDS) if event.type == pygame.MOUSEBUTTONDOWN and event.button == 1: if click_cooldown <= 0: src = SoundSource(event.pos[0], event.pos[1], KINDS[kind_idx]) src.play() sources.append(src) click_cooldown = 0.2 # Update sources for src in sources: src.update_spatial(listener_x, listener_y, dt) sources = [s for s in sources if s.alive] # ── DRAW ──────────────────────────────────────────────── screen.fill(DARK_BG) # Grid for gx in range(0, WIDTH, 80): pygame.draw.line(screen, (16, 16, 26), (gx, 0), (gx, HEIGHT)) for gy in range(0, HEIGHT, 80): pygame.draw.line(screen, (16, 16, 26), (0, gy), (WIDTH, gy)) # Max-distance circle around listener pygame.draw.circle(screen, (30, 30, 50), (listener_x, listener_y), int(MAX_DIST), 1) # Sources for src in sources: src.draw(screen, listener_x, listener_y) # Listener (ear icon) pygame.draw.circle(screen, WHITE, (listener_x, listener_y), 12) pygame.draw.circle(screen, BLUE, (listener_x, listener_y), 12, 2) lbl = F_SMALL.render("👂", True, WHITE) screen.blit(lbl, (listener_x - 6, listener_y - 8)) # Line from listener to each source for src in sources: dx = src.x - listener_x dy = src.y - listener_y dist = math.hypot(dx, dy) vol = max(0.0, 1.0 - dist / MAX_DIST) if vol > 0.05: pygame.draw.line(screen, (*src.color, int(vol * 80)), (listener_x, listener_y), (int(src.x), int(src.y)), 1) # ── HUD ──────────────────────────────────────────────── hud_y = HEIGHT - 80 pygame.draw.rect(screen, (12, 12, 20), (0, hud_y, WIDTH, 80)) pygame.draw.line(screen, GRAY, (0, hud_y), (WIDTH, hud_y), 1) blit(screen, f"Selected sound: {KINDS[kind_idx]} (TAB to cycle)", (20, hud_y + 8), YELLOW, F_MED) blit(screen, f"Active sources: {len(sources)} " f"| Ambient: {'ON' if ambient_channel and ambient_channel.get_busy() else 'OFF'}", (20, hud_y + 30), GRAY_LT, F_SMALL) blit(screen, "CLICK: spawn source | SPACE: ambient | TAB: change sound | ESC: quit", (20, hud_y + 48), GRAY, F_SMALL) # Stereo meter pan_x = listener_x / WIDTH blit(screen, "L", (WIDTH - 220, hud_y + 8), GRAY_LT, F_SMALL) pygame.draw.rect(screen, GRAY, (WIDTH - 200, hud_y + 12, 180, 10)) pygame.draw.rect(screen, BLUE, (WIDTH - 200, hud_y + 12, int(180 * pan_x), 10)) blit(screen, "R", (WIDTH - 16, hud_y + 8), GRAY_LT, F_SMALL) blit(screen, f"pan {pan_x:.2f}", (WIDTH - 200, hud_y + 28), GRAY, F_SMALL) pygame.display.flip()