GUI: higher quality oscilloscope

issue #1324

src/gui/gui.cpp

@@ -7102,8 +7102,11 @@ FurnaceGUI::FurnaceGUI():
   displayInternalPorts(false),
   subPortPos(0.0f,0.0f),
   oscTotal(0),
+  oscWidth(512),
   oscZoom(0.5f),
   oscWindowSize(20.0f),
+  oscInput(0.0f),
+  oscInput1(0.0f),
   oscZoomSlider(false),
   chanOscCols(3),
   chanOscAutoColsType(0),
@@ -7217,7 +7220,7 @@ FurnaceGUI::FurnaceGUI():
   memset(patChanX,0,sizeof(float)*(DIV_MAX_CHANS+1));
   memset(patChanSlideY,0,sizeof(float)*(DIV_MAX_CHANS+1));
   memset(lastIns,-1,sizeof(int)*DIV_MAX_CHANS);
-  memset(oscValues,0,sizeof(float)*512);
+  memset(oscValues,0,sizeof(float)*1024);
 
   memset(chanOscLP0,0,sizeof(float)*DIV_MAX_CHANS);
   memset(chanOscLP1,0,sizeof(float)*DIV_MAX_CHANS);

src/gui/gui.h

@@ -1969,10 +1969,11 @@ class FurnaceGUI {
   ImVec2 subPortPos;
 
   // oscilloscope
-  int oscTotal;
+  int oscTotal, oscWidth;
-  float oscValues[512];
+  float oscValues[1024];
   float oscZoom;
   float oscWindowSize;
+  float oscInput, oscInput1;
   bool oscZoomSlider;
 
   // per-channel oscilloscope

src/gui/osc.cpp

@@ -20,6 +20,8 @@
 #include "gui.h"
 #include "imgui_internal.h"
 #include <imgui.h>
+#include "../ta-log.h"
+#include "../engine/filter.h"
 
 void FurnaceGUI::readOsc() {
   int writePos=e->oscWritePos;
@@ -45,21 +47,81 @@ void FurnaceGUI::readOsc() {
   if (total>avail) total=avail;
   //printf("total: %d. avail: %d bias: %d\n",total,avail,bias);
 
+  memset(oscValues,0,1024*sizeof(float));
+
   int winSize=e->getAudioDescGot().rate*(oscWindowSize/1000.0);
   int oscReadPos=(writePos-winSize)&0x7fff;
-  for (int i=0; i<512; i++) {
-    int pos=(oscReadPos+(i*winSize/512))&0x7fff;
-    oscValues[i]=0;
-    for (int j=0; j<e->getAudioDescGot().outChans; j++) {
-      oscValues[i]+=e->oscBuf[j][pos];
-    }
-    oscValues[i]/=e->getAudioDescGot().outChans;
 
-    if (oscValues[i]>0.001f || oscValues[i]<-0.001f) {
+  float* sincITable=DivFilterTables::getSincIntegralTable();
-      WAKE_UP;
+
+  float posFrac=0.0;
+  int posInt=oscReadPos;
+  float factor=(float)oscWidth/(float)winSize;
+  for (int i=0; i<oscWidth; i++) {
+    float avg=0.0f;
+    float prevAvg=0.0f;
+    for (int j=0; j<e->getAudioDescGot().outChans; j++) {
+      avg+=e->oscBuf[j][posInt&0x7fff];
+    }
+    avg/=e->getAudioDescGot().outChans;
+    oscValues[i]+=avg;
+
+    posFrac+=1.0;
+    while (posFrac>=1.0) {
+      unsigned int n=((unsigned int)(posFrac*8192.0))&8191;
+      posFrac-=factor;
+      posInt++;
+
+      prevAvg=avg;
+      avg=0.0f;
+      for (int j=0; j<e->getAudioDescGot().outChans; j++) {
+        avg+=e->oscBuf[j][posInt&0x7fff];
+      }
+      avg/=e->getAudioDescGot().outChans;
+
+      float* t1=&sincITable[(8191-n)<<3];
+      float* t2=&sincITable[n<<3];
+      float delta=avg-prevAvg;
+
+      for (int j=0; j<8; j++) {
+        if (i-j>0) {
+          oscValues[i-j]+=t1[j]*-delta;
+        }
+        if (i+j+1<oscWidth) {
+          oscValues[i+j+1]+=t2[j]*delta;
+        }
+      }
     }
   }
 
+  /*
+  for (int i=0; i<winSize; i++) {
+    int pos=(oscReadPos+i)&0x7fff;
+    float avg=0.0f;
+    for (int j=0; j<e->getAudioDescGot().outChans; j++) {
+      avg+=e->oscBuf[j][pos];
+    }
+    avg/=e->getAudioDescGot().outChans;
+
+    //oscInput+=(avg-oscInput)*cut;
+    //oscInput1+=(oscInput1-oscInput)*cut;
+
+    oscInput=avg;
+
+    for (int j=(i*oscWidth)/winSize; j<((i+1)*oscWidth)/winSize; j++) {
+      if (j>=oscWidth) break;
+      oscValues[j]=oscInput;
+    }
+
+    if (avg>0.001f || avg<-0.001f) {
+      WAKE_UP;
+    }
+  }*/
+
+  /*for (int i=0; i<oscWidth; i++) {
+    oscValues[i]=(i&1)?0.3:0;
+  }*/
+
   float peakDecay=0.05f*60.0f*ImGui::GetIO().DeltaTime;
   for (int i=0; i<e->getAudioDescGot().outChans; i++) {
     peak[i]*=1.0-peakDecay;
@@ -124,7 +186,7 @@ void FurnaceGUI::drawOsc() {
     ImDrawList* dl=ImGui::GetWindowDrawList();
     ImGuiWindow* window=ImGui::GetCurrentWindow();
 
-    ImVec2 waveform[512];
+    ImVec2 waveform[1024];
     ImVec2 size=ImGui::GetContentRegionAvail();
 
     ImVec2 minArea=window->DC.CursorPos;
@@ -211,8 +273,12 @@ void FurnaceGUI::drawOsc() {
         dpiScale
       );
 
-      for (size_t i=0; i<512; i++) {
+      oscWidth=round(inRect.Max.x-inRect.Min.x);
-        float x=(float)i/512.0f;
+      if (oscWidth<1) oscWidth=1;
+      if (oscWidth>1024) oscWidth=1024;
+
+      for (int i=0; i<oscWidth; i++) {
+        float x=(float)i/(float)oscWidth;
         float y=oscValues[i]*oscZoom;
         if (!settings.oscEscapesBoundary) {
           if (y<-0.5f) y=-0.5f;
@@ -220,13 +286,16 @@ void FurnaceGUI::drawOsc() {
         }
         waveform[i]=ImLerp(inRect.Min,inRect.Max,ImVec2(x,0.5f-y));
       }
+      //ImDrawListFlags prevFlags=dl->Flags;
+      //dl->Flags&=~(ImDrawListFlags_AntiAliasedLines|ImDrawListFlags_AntiAliasedLinesUseTex);
       if (settings.oscEscapesBoundary) {
         dl->PushClipRectFullScreen();
-        dl->AddPolyline(waveform,512,color,ImDrawFlags_None,dpiScale);
+        dl->AddPolyline(waveform,oscWidth,color,ImDrawFlags_None,dpiScale);
         dl->PopClipRect();
       } else {
-        dl->AddPolyline(waveform,512,color,ImDrawFlags_None,dpiScale);
+        dl->AddPolyline(waveform,oscWidth,color,ImDrawFlags_None,dpiScale);
       }
+      //dl->Flags=prevFlags;
       if (settings.oscBorder) {
         dl->AddRect(inRect.Min,inRect.Max,borderColor,settings.oscRoundedCorners?(8.0f*dpiScale):0.0f,0,1.5f*dpiScale);
       }