import

2012-11-16 09:18:57 +01:00
commit ea6f1ef80a
79 changed files with 3595 additions and 0 deletions
--- a/Player/arm7/source/Envelope.c
+++ b/Player/arm7/source/Envelope.c
@@ -0,0 +1,85 @@
+#include "Envelope.h"
+#include "InstrumentParameters.h"
+
+#define MAX_VOLUME 512
+
+void Envelope_Init(Envelope * pEnvelope)
+{
+	pEnvelope->iTime = 0;
+	pEnvelope->iLastEnvelope = 0;
+	pEnvelope->iVelocity = 0;
+	pEnvelope->iState = RELEASE;
+}
+
+unsigned int Envelope_Compute(Envelope * pEnvelope, InstrumentParameters * pParameters)
+{
+	unsigned int iEnvelope = 0;
+
+	int iAttack = pParameters->iAttack;
+	int iDecay = pParameters->iDecay;
+	int iSustain = pParameters->iSustain * MAX_VOLUME / 127;
+	int iRelease = pParameters->iRelease;
+
+	pEnvelope->iTime++;
+
+	switch ( pEnvelope->iState )
+	{
+		case ATTACK:
+		{
+			iEnvelope = (pEnvelope->iTime * MAX_VOLUME) / iAttack;
+			if ( pEnvelope->iTime >= iAttack ) {
+				pEnvelope->iTime = 0;
+				pEnvelope->iState = DECAY;
+			}
+			break;
+		}
+
+		case DECAY:
+		{
+			int s = MAX_VOLUME - iSustain;
+			iEnvelope = iSustain + s - ((pEnvelope->iTime * s) / iDecay);
+			if ( pEnvelope->iTime >= iDecay ) {
+				pEnvelope->iTime = 0;
+				pEnvelope->iState = SUSTAIN;
+			}
+			break;
+		}
+
+		case SUSTAIN:
+		{
+			iEnvelope = iSustain;
+			break;
+		}
+
+		case RELEASE:
+		{
+			if ( pEnvelope->iTime <= iRelease )
+				iEnvelope = pEnvelope->iLastEnvelope -
+					((pEnvelope->iTime * pEnvelope->iLastEnvelope) / iRelease);
+			break;
+		}
+	}
+
+	if ( pEnvelope->iState != RELEASE )
+		pEnvelope->iLastEnvelope = iEnvelope;
+
+	iEnvelope = iEnvelope * pEnvelope->iVelocity / 127;
+
+	return iEnvelope / (MAX_VOLUME / 128);
+}
+
+void Envelope_NoteOn(Envelope * pEnvelope, int v)
+{
+	pEnvelope->iVelocity = v;
+	pEnvelope->iTime = 0;
+	pEnvelope->iState = ATTACK;
+}
+
+void Envelope_NoteOff(Envelope * pEnvelope)
+{
+	if ( pEnvelope->iState != RELEASE )
+	{
+		pEnvelope->iTime = 0;
+		pEnvelope->iState = RELEASE;
+	}
+}