Carla: Initial code for dry/wet latency compensation, working for VST

c++/carla-backend/carla_native.cpp

@@ -1294,7 +1294,7 @@ public:
                 {
                     for (k=0; k < frames; k++)
                     {
-                        if (aOut.count == 1)
+                        if (aIn.count == 1)
                             outBuffer[i][k] = (outBuffer[i][k]*x_dryWet)+(inBuffer[0][k]*(1.0-x_dryWet));
                         else
                             outBuffer[i][k] = (outBuffer[i][k]*x_dryWet)+(inBuffer[i][k]*(1.0-x_dryWet));

c++/carla-backend/carla_plugin.h

@@ -233,6 +233,10 @@ public:
 #endif
             m_ctrlInChannel = 0;
 
+        m_latency = 0;
+        m_tempBufferIn  = nullptr;
+        m_tempBufferOut = nullptr;
+
 #ifndef BUILD_BRIDGE
         osc.data.path   = nullptr;
         osc.data.source = nullptr;
@@ -305,6 +309,22 @@ public:
             custom.clear();
         }
 
+        if (m_tempBufferIn)
+        {
+            for (uint32_t i=0; i < aIn.count; i++)
+                delete[] m_tempBufferIn[i];
+
+            delete[] m_tempBufferIn;
+        }
+
+        if (m_tempBufferOut)
+        {
+            for (uint32_t i=0; i < aOut.count; i++)
+                delete[] m_tempBufferOut[i];
+
+            delete[] m_tempBufferOut;
+        }
+
         m_count -= 1;
     }
 
@@ -1367,7 +1387,49 @@ public:
      */
     virtual void bufferSizeChanged(const uint32_t newBufferSize)
     {
-        Q_UNUSED(newBufferSize);
+        recreateTempBuffers(newBufferSize);
+    }
+
+    /*!
+     * Recreate temporary audio buffers.
+     */
+    void recreateTempBuffers(const uint32_t bufferSize)
+    {
+        if (m_tempBufferIn)
+        {
+            for (uint32_t i=0; i < aIn.count; i++)
+                delete[] m_tempBufferIn[i];
+
+            delete[] m_tempBufferIn;
+        }
+
+        if (m_tempBufferOut)
+        {
+            for (uint32_t i=0; i < aOut.count; i++)
+                delete[] m_tempBufferOut[i];
+
+            delete[] m_tempBufferOut;
+        }
+
+        if (aIn.count > 0)
+        {
+            m_tempBufferIn = new float* [aIn.count];
+
+            for (uint32_t i=0; i < aIn.count; i++)
+                m_tempBufferIn[i] = new float [bufferSize];
+        }
+        else
+            m_tempBufferIn = nullptr;
+
+        if (aOut.count > 0)
+        {
+            m_tempBufferOut = new float* [aOut.count];
+
+            for (uint32_t i=0; i < aOut.count; i++)
+                m_tempBufferOut[i] = new float [bufferSize];
+        }
+        else
+            m_tempBufferOut = nullptr;
     }
 
     // -------------------------------------------------------------------
@@ -2177,7 +2239,11 @@ protected:
     const char* m_name;
     const char* m_filename;
 
-    int8_t m_ctrlInChannel;
+    int8_t  m_ctrlInChannel;
+
+    uint32_t m_latency;
+    float**  m_tempBufferIn;
+    float**  m_tempBufferOut;
 
     // -------------------------------------------------------------------
     // Storage Data

c++/carla-backend/dssi.cpp

@@ -699,7 +699,7 @@ public:
         // check latency
         {
             bool hasLatency = false;
-            uint32_t latency = 0;
+            m_latency = 0;
 
             for (uint32_t i=0; i < param.count; i++)
             {
@@ -731,7 +731,7 @@ public:
                     ldescriptor->run(handle, 2);
                     ldescriptor->deactivate(handle);
 
-                    latency = rint(paramBuffers[i]);
+                    m_latency = rint(paramBuffers[i]);
                     hasLatency = true;
                     break;
                 }
@@ -740,7 +740,7 @@ public:
             if (hasLatency)
             {
                 for (uint32_t i=0; i < aIn.count; i++)
-                    aIn.ports[i]->setLatency(latency);
+                    aIn.ports[i]->setLatency(m_latency);
 
                 x_client->recomputeLatencies();
             }
@@ -748,6 +748,7 @@ public:
 
         reloadPrograms(true);
 
+        recreateTempBuffers(x_engine->getBufferSize());
         x_client->activate();
 
         qDebug("DssiPlugin::reload() - end");
@@ -1303,7 +1304,7 @@ public:
                 {
                     for (k=0; k < frames; k++)
                     {
-                        if (aOut.count == 1)
+                        if (aIn.count == 1)
                             outBuffer[i][k] = (outBuffer[i][k]*x_dryWet)+(inBuffer[0][k]*(1.0-x_dryWet));
                         else
                             outBuffer[i][k] = (outBuffer[i][k]*x_dryWet)+(inBuffer[i][k]*(1.0-x_dryWet));

c++/carla-backend/ladspa.cpp

@@ -668,7 +668,7 @@ public:
         // check latency
         {
             bool hasLatency = false;
-            uint32_t latency = 0;
+            m_latency = 0;
 
             for (uint32_t i=0; i < param.count; i++)
             {
@@ -700,7 +700,7 @@ public:
                     descriptor->run(handle, 2);
                     descriptor->deactivate(handle);
 
-                    latency = rint(paramBuffers[i]);
+                    m_latency = rint(paramBuffers[i]);
                     hasLatency = true;
                     break;
                 }
@@ -709,12 +709,13 @@ public:
             if (hasLatency)
             {
                 for (uint32_t i=0; i < aIn.count; i++)
-                    aIn.ports[i]->setLatency(latency);
+                    aIn.ports[i]->setLatency(m_latency);
 
                 x_client->recomputeLatencies();
             }
         }
 
+        recreateTempBuffers(x_engine->getBufferSize());
         x_client->activate();
 
         qDebug("LadspaPlugin::reload() - end");
@@ -979,7 +980,7 @@ public:
                 {
                     for (k=0; k < frames; k++)
                     {
-                        if (aOut.count == 1)
+                        if (aIn.count == 1)
                             outBuffer[i][k] = (outBuffer[i][k]*x_dryWet)+(inBuffer[0][k]*(1.0-x_dryWet));
                         else
                             outBuffer[i][k] = (outBuffer[i][k]*x_dryWet)+(inBuffer[i][k]*(1.0-x_dryWet));

c++/carla-backend/lv2.cpp

@@ -1740,7 +1740,7 @@ public:
         // check latency
         {
             bool hasLatency = false;
-            uint32_t latency = 0;
+            m_latency = 0;
 
             for (uint32_t i=0; i < param.count; i++)
             {
@@ -1763,7 +1763,7 @@ public:
                     descriptor->run(handle, 0);
                     descriptor->deactivate(handle);
 
-                    latency = rint(paramBuffers[i]);
+                    m_latency = rint(paramBuffers[i]);
                     hasLatency = true;
                     break;
                 }
@@ -1772,7 +1772,7 @@ public:
             if (hasLatency)
             {
                 for (uint32_t i=0; i < aIn.count; i++)
-                    aIn.ports[i]->setLatency(latency);
+                    aIn.ports[i]->setLatency(m_latency);
 
                 x_client->recomputeLatencies();
             }
@@ -1780,6 +1780,7 @@ public:
 
         reloadPrograms(true);
 
+        recreateTempBuffers(x_engine->getBufferSize());
         x_client->activate();
 
         qDebug("Lv2Plugin::reload() - end");
@@ -2580,7 +2581,7 @@ public:
                 {
                     for (k=0; k < frames; k++)
                     {
-                        if (aOut.count == 1)
+                        if (aIn.count == 1)
                             outBuffer[i][k] = (outBuffer[i][k]*x_dryWet)+(inBuffer[0][k]*(1.0-x_dryWet));
                         else
                             outBuffer[i][k] = (outBuffer[i][k]*x_dryWet)+(inBuffer[i][k]*(1.0-x_dryWet));
@@ -2761,6 +2762,8 @@ public:
     void bufferSizeChanged(const uint32_t newBufferSize)
     {
         lv2Options.bufferSize = newBufferSize;
+
+        CarlaPlugin::bufferSizeChanged(newBufferSize);
     }
 
     // -------------------------------------------------------------------

c++/carla-backend/vst.cpp

@@ -734,19 +734,20 @@ public:
 #ifdef VESTIGE_HEADER
             char* const empty3Ptr = &effect->empty3[0];
             int32_t* initialDelayPtr = (int32_t*)empty3Ptr;
-            uint32_t latency = *initialDelayPtr;
+            m_latency = *initialDelayPtr;
 #else
-            uint32_t latency = effect->initialDelay;
+            m_latency = effect->initialDelay;
 #endif
 
             for (uint32_t i=0; i < aIn.count; i++)
-                aIn.ports[i]->setLatency(latency);
+                aIn.ports[i]->setLatency(m_latency);
 
             x_client->recomputeLatencies();
         }
 
         reloadPrograms(true);
 
+        recreateTempBuffers(x_engine->getBufferSize());
         x_client->activate();
 
         qDebug("VstPlugin::reload() - end");
@@ -1209,6 +1210,12 @@ public:
                     midiEventCount = MAX_MIDI_CHANNELS*2;
                 }
 
+                for (i=0; i < aIn.count; i++)
+                    memset(m_tempBufferIn[i], 0, sizeof(float)*x_engine->getBufferSize());
+
+                for (i=0; i < aOut.count; i++)
+                    memset(m_tempBufferOut[i], 0, sizeof(float)*x_engine->getBufferSize());
+
                 effect->dispatcher(effect, effStartProcess, 0, 0, nullptr, 0.0f);
             }
 
@@ -1260,7 +1267,7 @@ public:
             bool do_balance = (m_hints & PLUGIN_CAN_BALANCE) > 0 && (x_balanceLeft != -1.0 || x_balanceRight != 1.0);
 
             double bal_rangeL, bal_rangeR;
-            float oldBufLeft[do_balance ? frames : 0];
+            float bufValue, oldBufLeft[do_balance ? frames : 0];
 
             for (i=0; i < aOut.count; i++)
             {
@@ -1269,10 +1276,12 @@ public:
                 {
                     for (k=0; k < frames; k++)
                     {
-                        if (aOut.count == 1)
-                            outBuffer[i][k] = (outBuffer[i][k]*x_dryWet)+(inBuffer[0][k]*(1.0-x_dryWet));
+                        if (k < m_latency && m_latency < frames)
+                            bufValue = (aIn.count == 1) ? m_tempBufferIn[0][k] : m_tempBufferIn[i][k];
                         else
-                            outBuffer[i][k] = (outBuffer[i][k]*x_dryWet)+(inBuffer[i][k]*(1.0-x_dryWet));
+                            bufValue = (aIn.count == 1) ? inBuffer[0][k-m_latency] : inBuffer[i][k-m_latency];
+
+                        outBuffer[i][k] = (outBuffer[i][k]*x_dryWet)+(bufValue*(1.0-x_dryWet));
                     }
                 }
 
@@ -1316,6 +1325,13 @@ public:
                         aOutsPeak[i] = abs(outBuffer[i][k]);
                 }
             }
+
+            // Latency, save values for next callback
+            if (m_latency > 0 && m_latency < frames)
+            {
+                for (i=0; i < aIn.count; i++)
+                    memcpy(m_tempBufferIn[i], inBuffer[i] + (frames - m_latency), sizeof(float)*m_latency);
+            }
         }
         else
         {
@@ -1376,6 +1392,8 @@ public:
 
         if (m_active)
             effect->dispatcher(effect, effStartProcess, 0, 0, nullptr, 0.0f);
+
+        CarlaPlugin::bufferSizeChanged(newBufferSize);
     }
 
     // -------------------------------------------------------------------