Fix T83997: Duplicated audio does not sound the same

The issue was that sounds were always faded from 0 volume when they
started and depending on the currently used buffer size, the fading took
longer or shorter.

The solution stores whether the sound has ever been played back and
consequently does not fade when starting to play back.

2 files changed, 21 insertions, 1 deletions

diff --git a/extern/audaspace/include/devices/SoftwareDevice.h b/extern/audaspace/include/devices/SoftwareDevice.h
index e92a35e5402..a350550048b 100644
--- a/extern/audaspace/include/devices/SoftwareDevice.h
+++ b/extern/audaspace/include/devices/SoftwareDevice.h
@@ -72,6 +72,9 @@ protected:
 		/// The channel mapper reader in between.
 		std::shared_ptr<ChannelMapperReader> m_mapper;
 
+		/// Whether the source is being read for the first time.
+		bool m_first_reading;
+
 		/// Whether to keep the source if end of it is reached.
 		bool m_keep;
 
diff --git a/extern/audaspace/src/devices/SoftwareDevice.cpp b/extern/audaspace/src/devices/SoftwareDevice.cpp
index 7186f8b9442..c8c1c6081c2 100644
--- a/extern/audaspace/src/devices/SoftwareDevice.cpp
+++ b/extern/audaspace/src/devices/SoftwareDevice.cpp
@@ -78,7 +78,7 @@ bool SoftwareDevice::SoftwareHandle::pause(bool keep)
 }
 
 SoftwareDevice::SoftwareHandle::SoftwareHandle(SoftwareDevice* device, std::shared_ptr<IReader> reader, std::shared_ptr<PitchReader> pitch, std::shared_ptr<ResampleReader> resampler, std::shared_ptr<ChannelMapperReader> mapper, bool keep) :
-	m_reader(reader), m_pitch(pitch), m_resampler(resampler), m_mapper(mapper), m_keep(keep), m_user_pitch(1.0f), m_user_volume(1.0f), m_user_pan(0.0f), m_volume(0.0f), m_old_volume(0.0f), m_loopcount(0),
+	m_reader(reader), m_pitch(pitch), m_resampler(resampler), m_mapper(mapper), m_first_reading(true), m_keep(keep), m_user_pitch(1.0f), m_user_volume(1.0f), m_user_pan(0.0f), m_volume(0.0f), m_old_volume(0.0f), m_loopcount(0),
 	m_relative(true), m_volume_max(1.0f), m_volume_min(0), m_distance_max(std::numeric_limits<float>::max()),
 	m_distance_reference(1.0f), m_attenuation(1.0f), m_cone_angle_outer(M_PI), m_cone_angle_inner(M_PI), m_cone_volume_outer(0),
 	m_flags(RENDER_CONE), m_stop(nullptr), m_stop_data(nullptr), m_status(STATUS_PLAYING), m_device(device)
@@ -106,6 +106,14 @@ void SoftwareDevice::SoftwareHandle::update()
 	if(m_pitch->getSpecs().channels != CHANNELS_MONO)
 	{
 		m_volume = m_user_volume;
+
+		// we don't know a previous volume if this source has never been read before
+		if(m_first_reading)
+		{
+			m_old_volume = m_volume;
+			m_first_reading = false;
+		}
+
 		m_pitch->setPitch(m_user_pitch);
 		return;
 	}
@@ -214,6 +222,13 @@ void SoftwareDevice::SoftwareHandle::update()
 		m_volume *= m_user_volume;
 	}
 
+	// we don't know a previous volume if this source has never been read before
+	if(m_first_reading)
+	{
+		m_old_volume = m_volume;
+		m_first_reading = false;
+	}
+
 	// 3D Cue
 
 	Quaternion orientation;
@@ -754,6 +769,8 @@ void SoftwareDevice::mix(data_t* buffer, int length)
 				{
 					m_mixer->mix(buf, pos, len, sound->m_volume, sound->m_old_volume);
 
+					sound->m_old_volume = sound->m_volume;
+
 					pos += len;
 
 					if(sound->m_loopcount > 0)