uhh very cool game for cdww

function setup() {
  createCanvas(windowWidth, windowHeight, WEBGL);
  
  // Create UI overlay to trigger audio context
  startBtn = createButton('ENTER EXPERIENCE');
  startBtn.id('start-btn');
  startBtn.mousePressed(initAudio);
  
  liquidShader = createShader(vertShader, fragShader);
  noStroke();
}

function draw() {
  // Calculate instantaneous velocity
  let dx = mouseX - pmouseX;
  let dy = mouseY - pmouseY;

  // Smooth the velocity
  smoothVelX = lerp(smoothVelX, dx, 0.1);
  smoothVelY = lerp(smoothVelY, dy, 0.1);

  // Dampen velocity down to zero
  smoothVelX *= 0.96;
  smoothVelY *= 0.96;
  
  // --- AUDIO REACTIVITY ---
  if (audioStarted) {
    // Calculate the magnitude of our velocity
    let velMag = sqrt(smoothVelX * smoothVelX + smoothVelY * smoothVelY);
    
    // Map velocity to filter cutoff (low/muffled when still -> high/bright when moving fast)
    let targetFreq = map(velMag, 0, 40, 250, 8000, true);
    synthFilter.frequency.rampTo(targetFreq, 0.1);
    
    // Map velocity to volume (-20dB when still -> 0dB when moving)
    let targetVol = map(velMag, 0, 30, -20, 0, true);
    masterVolume.volume.rampTo(targetVol, 0.1);
  }

  // Activate shader
  shader(liquidShader);

  // Pass uniforms
  liquidShader.setUniform('u_resolution', [width, height]);
  liquidShader.setUniform('u_time', millis() / 1000.0);
  liquidShader.setUniform('u_mouse', [mouseX, mouseY]);
  liquidShader.setUniform('u_mouse_vel', [smoothVelX, smoothVelY]);

  // Draw fullscreen quad
  rect(-width / 2, -height / 2, width, height);
}

async function initAudio() {
  // Required: Start Tone context on user gesture
  await Tone.start();
  
  // Create master effects nodes controlled by the mouse movement
  masterVolume = new Tone.Volume(-20).toDestination();
  synthFilter = new Tone.Filter(250, "lowpass").connect(masterVolume);
  
  // 1. Kick Drum
  const kick = new Tone.MembraneSynth({
    pitchDecay: 0.05,
    octaves: 4,
    oscillator: { type: "sine" },
    envelope: { attack: 0.001, decay: 0.4, sustain: 0.01, release: 1.4 }
  }).connect(synthFilter);
  
  // 2. Gritty FM Bassline
  const bass = new Tone.FMSynth({
    harmonicity: 1,
    modulationIndex: 2,
    oscillator: { type: "square" },
    envelope: { attack: 0.01, decay: 0.2, sustain: 0.1, release: 0.5 }
  }).connect(synthFilter);
  
  // 3. Hi-Hat
  const hihat = new Tone.NoiseSynth({
    noise: { type: "white" },
    envelope: { attack: 0.001, decay: 0.1, sustain: 0, release: 0.1 }
  }).connect(synthFilter);
  
  // Bassline notes pattern
  const bassNotes = ["C2", "C2", "Eb2", "C2", "F2", "C2", "Bb1", "C2"];
  
  // Sequencer loop (16th notes)
  let step = 0;
  Tone.Transport.scheduleRepeat((time) => {
    // 4/4 Kick on the downbeat (0, 4, 8, 12)
    if (step % 4 === 0) {
      kick.triggerAttackRelease("C1", "8n", time);
    }
    
    // Offbeat hi-hat (2, 6, 10, 14)
    if (step % 4 === 2) {
      hihat.triggerAttackRelease("16n", time, 0.3);
    }
    
    // Driving 16th note bassline (skipping the kick beats)
    if (step % 4 !== 0) {
      bass.triggerAttackRelease(bassNotes[step % 8], "16n", time, 0.5);
    }
    
    step = (step + 1) % 16;
  }, "16n");

  // Set BPM and start transport
  Tone.Transport.bpm.value = 130;
  Tone.Transport.start();
  
  // Clean up UI and update state
  audioStarted = true;
  startBtn.remove();
}

function windowResized() {
  resizeCanvas(windowWidth, windowHeight);
}