Did more commenting, did minor code corrections.

Author: konsfik

3-Procedural-Audio/ProceduralAudioUnityProject/Assets/Materials/BlueMaterial.mat

@@ -11,15 +11,14 @@
 public class ProceduralAudioController : MonoBehaviour {
 /* This class is the main audio engine, that has certain embedded functions to it, so that
 you may produce some interesting audio results.*/
+
 SawWave sawAudioWave;
 SquareWave squareAudioWave;
 SinusWave sinusAudioWave;
 
 SinusWave amplitudeModulationOscillator;
 SinusWave frequencyModulationOscillator;
-//SinusWave amOsc;
-float tt;
-float ttPrev;
+
 public bool autoPlay;
 
 [Header("Volume / Frequency")]
@@ -66,11 +65,12 @@ you may produce some interesting audio results.*/
 private System.Random RandomNumber = new System.Random();
 
 private double sampleRate;// samples per second
-private double myDspTime;// dsp time
-private double dataLen;//the data length of each channel
-double chunkTime;
-double stepTime;
-double currentTime;
+//private double myDspTime;	// dsp time
+private double dataLen;// the data length of each channel
+double chunkTime;
+double dspTimeStep;
+double currentDspTime;
+
 void Awake(){
 sawAudioWave = new SawWave ();
 squareAudioWave = new SquareWave ();
@@ -80,13 +80,11 @@ void Awake(){
 frequencyModulationOscillator = new SinusWave ();
 
 sampleRate = AudioSettings.outputSampleRate;
-myDspTime = AudioSettings.dspTime;
-currentTime = 0;
 }
 
 void Update(){
 if (autoPlay) {
-mainFrequency = Mathf.PingPong (Time.time*200.0f, 1900.0f) + 100.0f;
+mainFrequency = Mathf.PingPong (Time.time *200.0f, 1900.0f) + 100.0f;
 sinusAudioWaveIntensity = Mathf.PingPong (Time.time * 0.5f, 1.0f);
 squareAudioWaveIntensity = Mathf.PingPong (Time.time * 0.6f, 1.0f);
 sawAudioWaveIntensity = Mathf.PingPong (Time.time * 0.7f, 1.0f);
@@ -97,35 +95,48 @@ void Update(){
 }
 
 void OnAudioFilterRead(float[] data, int channels){
-currentTime = AudioSettings.dspTime;
+/* This is called by the system
+suppose: sampleRate = 48000
+suppose: data.Length = 2048
+suppose: channels = 2
+then:
+dataLen = 2048/2 = 1024
+chunkTime = 1024 / 48000 = 0.0213333... so the chunk time is around 21.3 milliseconds.
+dspTimeStep = 0.0213333 / 1024 = 2.083333.. * 10^(-5) = 0.00002083333..sec = 0.02083 milliseconds
+keep note that 1 / dspTimeStep = 48000 ok!
+*/
+
+currentDspTime = AudioSettings.dspTime;
 dataLen = data.Length / channels;// the actual data length for each channel
 chunkTime = dataLen / sampleRate;// the time that each chunk of data lasts
-stepTime = chunkTime / dataLen;
+dspTimeStep = chunkTime / dataLen;// the time of each dsp step. (the time that each individual audio sample (actually a float value) lasts)
+
+double preciseDspTime;
 for (int i = 0; i < dataLen; i++){ // go through data chunk
-double tt = currentTime + i * stepTime;
+preciseDspTime = currentDspTime + i * dspTimeStep;
 double signalValue = 0.0;
 double currentFreq = mainFrequency;
 if (useFrequencyModulation) {
 double freqOffset = (frequencyModulationOscillatorIntensity * mainFrequency * 0.75) / 100.0;
-currentFreq += mapValueD (frequencyModulationOscillator.calculateSignalValue (tt, frequencyModulationOscillatorFrequency), -1.0, 1.0, -freqOffset, freqOffset);
-frequencyModulationRangeOut = (float)frequencyModulationOscillator.calculateSignalValue (tt, frequencyModulationOscillatorFrequency) * 0.5f + 0.5f;
+currentFreq += mapValueD (frequencyModulationOscillator.calculateSignalValue (preciseDspTime, frequencyModulationOscillatorFrequency), -1.0, 1.0, -freqOffset, freqOffset);
+frequencyModulationRangeOut = (float)frequencyModulationOscillator.calculateSignalValue (preciseDspTime, frequencyModulationOscillatorFrequency) * 0.5f + 0.5f;
 } else {
 frequencyModulationRangeOut = 0.0f;
 }
 
 if (useSinusAudioWave) {
-signalValue += sinusAudioWaveIntensity * sinusAudioWave.calculateSignalValue (tt, currentFreq);
+signalValue += sinusAudioWaveIntensity * sinusAudioWave.calculateSignalValue (preciseDspTime, currentFreq);
 }
 if (useSawAudioWave) {
-signalValue += sawAudioWaveIntensity * sawAudioWave.calculateSignalValue (tt, currentFreq);
+signalValue += sawAudioWaveIntensity * sawAudioWave.calculateSignalValue (preciseDspTime, currentFreq);
 }
 if (useSquareAudioWave) {
-signalValue += squareAudioWaveIntensity * squareAudioWave.calculateSignalValue (tt, currentFreq);
+signalValue += squareAudioWaveIntensity * squareAudioWave.calculateSignalValue (preciseDspTime, currentFreq);
 }
 
 if (useAmplitudeModulation) {
-signalValue *= mapValueD (amplitudeModulationOscillator.calculateSignalValue (tt, amplitudeModulationOscillatorFrequency), -1.0, 1.0, 0.0, 1.0);
-amplitudeModulationRangeOut = (float)amplitudeModulationOscillator.calculateSignalValue (tt, amplitudeModulationOscillatorFrequency) * 0.5f + 0.5f;
+signalValue *= mapValueD (amplitudeModulationOscillator.calculateSignalValue (preciseDspTime, amplitudeModulationOscillatorFrequency), -1.0, 1.0, 0.0, 1.0);
+amplitudeModulationRangeOut = (float)amplitudeModulationOscillator.calculateSignalValue (preciseDspTime, amplitudeModulationOscillatorFrequency) * 0.5f + 0.5f;
 } else {
 amplitudeModulationRangeOut = 0.0f;
 }

3-Procedural-Audio/ProceduralAudioUnityProject/Assets/Materials/GreenMaterial.mat

@@ -25,6 +25,7 @@ void Start () {
 GameObject instance = Instantiate (spectrumCubePrefab, cubePos, Quaternion.identity);
 Quaternion rot = Quaternion.Euler(0.0f, i * 2.0f, 0.0f);
 instance.transform.rotation = rot;
+instance.transform.parent = this.transform;
 cubes.Add (instance);
 }
 }