fix #271723: support for opcodes required for percussion library

delay, pan (there is a bug - effects are applied despite on pan mixing
channels), offset, group_volume support

zerberus/sfz.cpp

@@ -89,6 +89,10 @@ struct SfzRegion {
       LoopMode loop_mode;
       OffMode off_mode;
       std::map<int, double> gain_oncc;
+      float delay; //seconds
+      int pan;    // [-100, 100]
+      unsigned long offset; // [0, 4Gb) or [0, 4294967295]
+      float group_volume; // [-144 to 6] (dB)
 
       void init(const QString&);
       bool isEmpty() const { return sample.isEmpty(); }
@@ -150,6 +154,10 @@ void SfzRegion::init(const QString& _path)
       use_cc         = false;
       off_mode = OffMode::FAST;
       gain_oncc.clear();
+      delay = 0.0f;
+      pan = 0;
+      offset = 0;
+      group_volume = 0.0f;
       }
 
 //---------------------------------------------------------
@@ -164,7 +172,7 @@ void SfzRegion::setZone(Zone* z) const
       z->veloLo       = lovel;
       z->veloHi       = hivel;
       z->keyBase      = pitch_keycenter;
-      z->offset       = 0;
+      z->offset       = offset;
       z->volume       = pow(10.0, volume / 20.0);
       z->ampVeltrack  = amp_veltrack;
       z->ampegAttack  = ampeg_attack * 1000;
@@ -204,6 +212,9 @@ void SfzRegion::setZone(Zone* z) const
       z->loopEnd      = loopEnd;
       z->loopStart    = loopStart;
       z->gainOnCC     = gain_oncc;
+      z->delay        = delay * 1000; //convert seconds from sfz to ms for computations
+      z->pan          = pan;
+      z->group_volume = pow(10.0, group_volume / 20.0); //dB -> volume multiplier
       }
 
 //---------------------------------------------------------
@@ -278,6 +289,18 @@ void ZInstrument::addRegion(SfzRegion& r)
             addZone(z);
       }
 
+//---------------------------------------------------------
+//   readFloat
+//---------------------------------------------------------
+
+static void readFloat(const QString& data, float& val)
+      {
+      bool ok;
+      float d = data.toFloat(&ok);
+      if (ok)
+            val = d;
+      }
+
 //---------------------------------------------------------
 //   readDouble
 //---------------------------------------------------------
@@ -480,6 +503,14 @@ void SfzRegion::readOp(const QString& b, const QString& data, SfzControl &c)
             seq_position = i;
       else if (opcode == "transpose")
             transpose = i;
+      else if (opcode == "delay")
+            readFloat(opcode_data, delay);
+      else if (opcode == "pan")
+            pan = i;
+      else if (opcode == "offset")
+            offset = opcode_data.toULong();
+      else if (opcode == "group_volume")
+            readFloat(opcode_data, group_volume);
       else
             qDebug("SfzRegion: unknown opcode <%s>", qPrintable(opcode));
       }

zerberus/voice.cpp

@@ -107,7 +107,8 @@ void Voice::start(Channel* c, int key, int v, const Zone* zone, double durSinceN
       Sample* s = z->sample;
       audioChan = s->channel();
       data      = s->data() + z->offset * audioChan;
-      eidx      = s->frames() * audioChan;
+      //avoid processing sample if offset is bigger than sample length
+      eidx      = std::max((s->frames() - long(z->offset) - 1) * audioChan, long(0));
       _loopMode = z->loopMode;
       _loopStart = z->loopStart;
       _loopEnd   = z->loopEnd;
@@ -134,7 +135,7 @@ void Voice::start(Channel* c, int key, int v, const Zone* zone, double durSinceN
       //    -> afterwards 0.5 (-6dB) is applied to compensate possible coherent
       //       signals in a stereo output see http://www.sengpielaudio.com/calculator-coherentsources.htm
       //    -> 0.005 = 0.01 * 0.5
-      gain        = z->volume * (offset + z->ampVeltrack * curve)
+      gain        = (z->volume * z->group_volume) * (offset + z->ampVeltrack * curve)
                     * .005 * c->gain() * rt_decay_value;
 
       phase.set(0);
@@ -166,7 +167,7 @@ void Voice::start(Channel* c, int key, int v, const Zone* zone, double durSinceN
       float velPercent = _velocity / 127.0;
 
       envelopes[V1Envelopes::DELAY].setTable(Envelope::egLin);
-      envelopes[V1Envelopes::DELAY].setTime(z->ampegDelay + (z->ampegVel2Delay * velPercent), _zerberus->sampleRate());
+      envelopes[V1Envelopes::DELAY].setTime(z->ampegDelay + (z->ampegVel2Delay * velPercent) + z->delay, _zerberus->sampleRate());
       envelopes[V1Envelopes::DELAY].setConstant(0.0);
 
       envelopes[V1Envelopes::ATTACK].setTable(Envelope::egLin);
@@ -325,6 +326,8 @@ void Voice::process(int frames, float* p)
             last_fres = _fres;
             }
 
+      const float opcodePanLeftGain = 1.f - std::fmax(0.0f, z->pan / 100.0); //[0, 1]
+      const float opcodePanRightGain = 1.f + std::fmin(0.0f, z->pan / 100.0); //[0, 1]
       if (audioChan == 1) {
             while (frames--) {
 
@@ -361,9 +364,11 @@ void Voice::process(int frames, float* p)
                         break;
                   v *= envelopes[currentEnvelope].val * z->ccGain;
 
-                  *p++  += v * _channel->panLeftGain();
-                  *p++  += v * _channel->panRightGain();
-                  phase += phaseIncr;
+                  *p++  += v * _channel->panLeftGain() * opcodePanLeftGain;
+                  *p++  += v * _channel->panRightGain() * opcodePanRightGain;
+                  if (V1Envelopes::DELAY != currentEnvelope)
+                        phase += phaseIncr;
+
                   _samplesSinceStart++;
                   }
             }
@@ -422,9 +427,12 @@ void Voice::process(int frames, float* p)
                         b1  += b1_incr;
                         }
 
-                  *p++  += vl;
-                  *p++  += vr;
-                  phase += phaseIncr;
+                  *p++  += vl * opcodePanLeftGain;
+                  *p++  += vr * opcodePanRightGain;
+
+                  if (V1Envelopes::DELAY != currentEnvelope)
+                        phase += phaseIncr;
+
                   _samplesSinceStart++;
                   }
             }

zerberus/zone.h

@@ -46,7 +46,7 @@ enum class OffMode : char {
 
 struct Zone {
       Sample* sample = 0;
-      int  offset  = 0;
+      unsigned long offset  = 0; //[0, 4294967295]
       int  seq     = 0;
       int seqLen   = 0;
       int seqPos   = 0;
@@ -76,6 +76,9 @@ struct Zone {
       float ampegVel2Sustain  = 0.0;
       float ampegVel2Release  = 0.0;
       float rtDecay = 0.0;
+      float delay = 0.0;
+      int pan = 0;
+      float group_volume = 1.0;
 
       Trigger trigger = Trigger::ATTACK;
       LoopMode loopMode = LoopMode::NO_LOOP;