plumb URDF/SDF audio_source into PhysicsServerCommandProcessor, allow to play sounds on collision !

See also https://youtu.be/eppOjTfx5Jg for a first test, and this modified URDF how to add sounds:
https://github.com/bulletphysics/bullet3/blob/master/data/plane_with_collision_audio.urdf
Add the --audio flag to enable sound in pybullet/Bullet-C-API

examples/TinyAudio/b3ADSR.cpp

@@ -23,6 +23,7 @@ b3ADSR::b3ADSR()
 	m_releaseRate = 0.0005;
 	m_sustainLevel = 0.5;
 	m_state = ADSR_IDLE;
+	m_autoKeyOff = false;
 }
 
 b3ADSR::~b3ADSR()
@@ -51,6 +52,10 @@ double b3ADSR::tick()
 				{
 					m_value = m_sustainLevel;
 					m_state = ADSR_SUSTAIN;
+					if (m_autoKeyOff)
+					{
+						keyOff();
+					}
 				}
 			}
 			else
@@ -60,6 +65,11 @@ double b3ADSR::tick()
 				{
 					m_value = m_sustainLevel;
 					m_state = ADSR_SUSTAIN;
+					if (m_autoKeyOff)
+					{
+						keyOff();
+					}
+
 				}
 			}
 			break;
@@ -81,8 +91,9 @@ bool b3ADSR::isIdle() const
 	return m_state == ADSR_IDLE;
 }
 
-void b3ADSR::keyOn()
+void b3ADSR::keyOn(bool autoKeyOff)
 {
+	m_autoKeyOff = autoKeyOff;
 	if (m_target <= 0.0)
 		m_target = 1.0;
 	if (m_attackRate==1)
@@ -94,6 +105,7 @@ void b3ADSR::keyOn()
 
 void b3ADSR::keyOff()
 {
+	m_autoKeyOff = false;
 	m_target = 0.0;
 	m_state = ADSR_RELEASE;
 

examples/TinyAudio/b3ADSR.h

@@ -11,7 +11,7 @@ class b3ADSR
 	double m_releaseRate;
 	double m_releaseTime;
 	double m_sustainLevel;
-
+	bool m_autoKeyOff;
 public:
 
 	b3ADSR();
@@ -19,7 +19,7 @@ public:
 
 	double tick();
 	bool isIdle() const;
-	void keyOn();
+	void keyOn(bool autoKeyOff);
 	void keyOff();
 
 	void setValues(double attack,double decay,double sustain,double release)

examples/TinyAudio/b3SoundEngine.cpp

@@ -7,6 +7,8 @@
 #include "Bullet3Common/b3AlignedObjectArray.h"
 #include "b3ReadWavFile.h"
 #include "../Utils/b3ResourcePath.h"
+#include "../Utils/b3HashString.h"
+
 #include "Bullet3Common/b3HashMap.h"
 
 // The default real-time audio input and output buffer size.  If
@@ -24,6 +26,8 @@ struct b3SoundEngineInternalData
 
 	b3AlignedObjectArray<b3SoundSource*> m_soundSources;
 	b3HashMap<b3HashInt, b3ReadWavFile*> m_wavFiles;
+	b3HashMap<b3HashString, int> m_name2wav;
+
 	int m_wavFileUidGenerator;
 
 	b3SoundEngineInternalData()
@@ -84,6 +88,19 @@ void b3SoundEngine::exit()
 		delete m_data->m_soundSources[i];
 	}
 	m_data->m_soundSources.clear();
+
+	for (int i=0;i<m_data->m_wavFiles.size();i++)
+	{
+		b3ReadWavFile** wavPtr = m_data->m_wavFiles.getAtIndex(i);
+		if (wavPtr && *wavPtr)
+		{
+			b3ReadWavFile* wav = *wavPtr;
+			delete wav;
+		}
+	}
+	m_data->m_wavFiles.clear();
+	m_data->m_name2wav.clear();
+
 }
 
 int b3SoundEngine::getAvailableSoundSource()
@@ -113,7 +130,7 @@ void b3SoundEngine::startSound(int soundSourceIndex, b3SoundMessage msg)
 			soundSource->setOscillatorFrequency(0, msg.m_frequency);
 			soundSource->setOscillatorFrequency(1, msg.m_frequency);
 			
-			soundSource->startSound();
+			soundSource->startSound(msg.m_autoKeyOff);
 			break;
 		}
 		case B3_SOUND_SOURCE_WAV_FILE:
@@ -124,7 +141,7 @@ void b3SoundEngine::startSound(int soundSourceIndex, b3SoundMessage msg)
 				b3ReadWavFile* wavFile = *wavFilePtr;
 				soundSource->setWavFile(0,wavFile,getSampleRate());
 				soundSource->setWavFile(1,wavFile,getSampleRate());
-				soundSource->startSound();
+				soundSource->startSound(msg.m_autoKeyOff);
 			}
 			break;
 		}
@@ -142,6 +159,11 @@ void b3SoundEngine::releaseSound(int soundSourceIndex)
 
 int b3SoundEngine::loadWavFile(const char* fileName)
 {
+	int* wavUidPtr = m_data->m_name2wav[fileName];
+	if (wavUidPtr)
+	{
+		return *wavUidPtr;
+	}
 	char resourcePath[1024];
 
 	if (b3ResourcePath::findResourcePath(fileName, resourcePath, 1024))
@@ -153,6 +175,7 @@ int b3SoundEngine::loadWavFile(const char* fileName)
 		wavFile->normalize(1);
 		int wavUID = m_data->m_wavFileUidGenerator++;
 		m_data->m_wavFiles.insert(wavUID, wavFile);
+		m_data->m_name2wav.insert(fileName,wavUID);
 		return wavUID;
 	}
 	return 0;

examples/TinyAudio/b3SoundEngine.h

@@ -16,6 +16,7 @@ struct b3SoundMessage
 	double m_decayRate;
 	double m_sustainLevel;
 	double m_releaseRate;
+	bool m_autoKeyOff;
 
 	b3SoundMessage()
 		:m_type(B3_SOUND_SOURCE_SINE_OSCILLATOR),
@@ -25,7 +26,8 @@ struct b3SoundMessage
 		m_attackRate(0.001),
 		m_decayRate(0.00001),
 		m_sustainLevel(0.5),
-		m_releaseRate(0.0005)
+		m_releaseRate(0.0005),
+		m_autoKeyOff(false)
 	{
 	}
 };

examples/TinyAudio/b3SoundSource.cpp

@@ -183,7 +183,7 @@ bool b3SoundSource::isAvailable() const
 	return m_data->m_envelope.isIdle();
 }
 
-void b3SoundSource::startSound()
+void b3SoundSource::startSound(bool autoKeyOff)
 {
 	if (m_data->m_envelope.isIdle())
 	{
@@ -209,7 +209,7 @@ void b3SoundSource::startSound()
 			}
 		}
 	}
-	m_data->m_envelope.keyOn();
+	m_data->m_envelope.keyOn(autoKeyOff);
 }
 
 void b3SoundSource::stopSound()

examples/TinyAudio/b3SoundSource.h

@@ -24,7 +24,7 @@ public:
 
 	bool setWavFile(int oscillatorIndex, class b3ReadWavFile* wavFilePtr, int sampleRate);
 
-	void startSound();
+	void startSound(bool autoKeyOff);
 	void stopSound();
 
 	bool isAvailable() const;