1 files changed, 115 insertions, 0 deletions
diff --git a/extern/audaspace/src/fx/ADSRReader.cpp b/extern/audaspace/src/fx/ADSRReader.cpp
new file mode 100644
index 00000000000..6499b55468e
--- /dev/null
+++ b/extern/audaspace/src/fx/ADSRReader.cpp
@@ -0,0 +1,115 @@
+/*******************************************************************************
+ * Copyright 2009-2016 Jörg Müller
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ ******************************************************************************/
+
+#include "fx/ADSRReader.h"
+
+AUD_NAMESPACE_BEGIN
+
+ADSRReader::ADSRReader(std::shared_ptr<IReader> reader, float attack, float decay, float sustain, float release) :
+	EffectReader(reader),
+	m_attack(attack), m_decay(decay), m_sustain(sustain), m_release(release)
+{
+	nextState(ADSR_STATE_ATTACK);
+}
+
+ADSRReader::~ADSRReader()
+{
+}
+
+void ADSRReader::nextState(ADSRState state)
+{
+	m_state = state;
+
+	switch(m_state)
+	{
+	case ADSR_STATE_ATTACK:
+		m_level = 0;
+		if(m_attack <= 0)
+		{
+			nextState(ADSR_STATE_DECAY);
+			return;
+		}
+		return;
+	case ADSR_STATE_DECAY:
+		if(m_decay <= 0)
+		{
+			nextState(ADSR_STATE_SUSTAIN);
+			return;
+		}
+		if(m_level > 1.0)
+			m_level = 1 - (m_level - 1) * m_attack / m_decay * (1 - m_sustain);
+		if(m_level <= m_sustain)
+			nextState(ADSR_STATE_SUSTAIN);
+		break;
+	case ADSR_STATE_SUSTAIN:
+		m_level = m_sustain;
+		break;
+	case ADSR_STATE_RELEASE:
+		if(m_release <= 0)
+		{
+			nextState(ADSR_STATE_INVALID);
+			return;
+		}
+		break;
+	case ADSR_STATE_INVALID:
+		break;
+	}
+}
+
+void ADSRReader::read(int & length, bool &eos, sample_t* buffer)
+{
+	Specs specs = m_reader->getSpecs();
+	m_reader->read(length, eos, buffer);
+
+	for(int i = 0; i < length; i++)
+	{
+		for(int channel = 0; channel < specs.channels; channel++)
+		{
+			buffer[i * specs.channels + channel] *= m_level;
+		}
+
+		switch(m_state)
+		{
+		case ADSR_STATE_ATTACK:
+			m_level += 1 / m_attack / specs.rate;
+			if(m_level >= 1)
+				nextState(ADSR_STATE_DECAY);
+			break;
+		case ADSR_STATE_DECAY:
+			m_level -= (1 - m_sustain) /  m_decay / specs.rate;
+			if(m_level <= m_sustain)
+				nextState(ADSR_STATE_SUSTAIN);
+			break;
+		case ADSR_STATE_SUSTAIN:
+			break;
+		case ADSR_STATE_RELEASE:
+			m_level -= m_sustain / m_release / specs.rate ;
+			if(m_level <= 0)
+				nextState(ADSR_STATE_INVALID);
+			break;
+		case ADSR_STATE_INVALID:
+			length = i;
+			return;
+		}
+	}
+}
+
+void ADSRReader::release()
+{
+	nextState(ADSR_STATE_RELEASE);
+}
+
+AUD_NAMESPACE_END