GUI: add a preliminary oscilloscope

src/engine/engine.cpp

@@ -4857,6 +4857,7 @@ bool DivEngine::initAudioBackend() {
     output=NULL;
     return false;
   }
+
   return true;
 }
 
@@ -4931,6 +4932,9 @@ bool DivEngine::init() {
     isMuted[i]=0;
   }
 
+  oscBuf[0]=new float[32768];
+  oscBuf[1]=new float[32768];
+
   initDispatch();
   reset();
   active=true;
@@ -4948,5 +4952,7 @@ bool DivEngine::quit() {
   logI("saving config.\n");
   saveConf();
   active=false;
+  delete[] oscBuf[0];
+  delete[] oscBuf[1];
   return true;
 }

src/engine/engine.h

@@ -206,6 +206,8 @@ class DivEngine {
     DivSystem sysOfChan[DIV_MAX_CHANS];
     int dispatchOfChan[DIV_MAX_CHANS];
     int dispatchChanOfChan[DIV_MAX_CHANS];
+    float* oscBuf[2];
+    float oscSize;
 
     void runExportThread();
     void nextBuf(float** in, float** out, int inChans, int outChans, unsigned int size);
@@ -549,6 +551,8 @@ class DivEngine {
       metroAmp(0.0f),
       totalProcessed(0),
       jediTable(NULL),
+      oscBuf{NULL,NULL},
+      oscSize(1),
       adpcmMem(NULL),
       adpcmMemLen(0) {}
 };

src/engine/playback.cpp

@@ -1138,5 +1138,10 @@ void DivEngine::nextBuf(float** in, float** out, int inChans, int outChans, unsi
     metroPos+=metroFreq;
     while (metroPos>=1) metroPos--;
   }
+
+  // TODO: improve
+  memcpy(oscBuf[0],out[0],size*sizeof(float));
+  memcpy(oscBuf[1],out[1],size*sizeof(float));
+  oscSize=size;
   isBusy.unlock();
 }