Add CPU Usage to the main panel in new layout (#339)

With a simple timer over available block calculation

Author: baconpaul

src/synth/synth.cpp

@@ -234,6 +234,7 @@ void Synth::setSampleRate(double sampleRate)
 
 template <bool multiOut> void Synth::processInternal(const clap_output_events_t *outq)
 {
+    auto start = std::chrono::high_resolution_clock::now();
     if (!SinTable::staticsInitialized)
         SinTable::initializeStatics();
 
@@ -465,6 +466,10 @@ template <bool multiOut> void Synth::processInternal(const clap_output_events_t
 
                 AudioToUIMsg msg2{AudioToUIMsg::UPDATE_VOICE_COUNT, (uint32_t)voiceCount};
                 audioToUi.push(msg2);
+
+                AudioToUIMsg msg3{AudioToUIMsg::UPDATE_CPU_USAGE, 0, (float)(cpuUsage * 100)};
+                audioToUi.push(msg3);
+
                 lastVuUpdate = 0;
             }
             else
@@ -522,6 +527,18 @@ template <bool multiOut> void Synth::processInternal(const clap_output_events_t
             resampler[0]->renormalizePhases();
         }
     }
+
+    // Finish CPU calculation
+    if (isEditorAttached)
+    {
+        auto end = std::chrono::high_resolution_clock::now();
+        auto duration = std::chrono::duration_cast<std::chrono::nanoseconds>(end - start);
+        auto micros = duration.count();
+        auto availmicrosinv = hostSampleRate * 1e-9 / blockSize;
+        auto pct = micros * availmicrosinv;
+        auto cpuFac = 0.995;
+        cpuUsage = cpuUsage * cpuFac + pct * (1 - cpuFac);
+    }
 }
 
 void Synth::process(const clap_output_events_t *o)

src/synth/synth.h

@@ -336,6 +336,7 @@ struct Synth
             UPDATE_PARAM,
             UPDATE_VU,
             UPDATE_VOICE_COUNT,
+            UPDATE_CPU_USAGE,
             SET_PATCH_NAME,
             SET_PATCH_DIRTY_STATE,
             DO_PARAM_RESCAN,
@@ -422,6 +423,7 @@ struct Synth
 
     sst::basic_blocks::dsp::VUPeak vuPeak;
     std::array<sst::basic_blocks::dsp::VUPeak, numOps> opVuPeak;
+    double cpuUsage{0};
     int32_t updateVuEvery{(int32_t)(48000 * 2.5 / 60 / blockSize)}; // approx
     int32_t lastVuUpdate{updateVuEvery};
 

src/ui/settings-panel.h

@@ -20,6 +20,7 @@
 #include <sst/jucegui/components/NamedPanel.h>
 #include <sst/jucegui/components/ToggleButton.h>
 #include <sst/jucegui/component-adapters/DiscreteToReference.h>
+#include <fmt/core.h>
 #include "six-sines-editor.h"
 
 namespace baconpaul::six_sines::ui
@@ -34,9 +35,19 @@ struct SettingsPanel : jcmp::NamedPanel, HasEditor
     void clearHighlight();
 
     void setVoiceCount(int vc) { voiceCount->setText("Voices: " + std::to_string(vc)); }
+    void setCpuUsage(double cpu)
+    {
+        if (std::round(cpu) != std::round(lastCpu))
+        {
+            cpuLabel->setText(fmt::format("CPU: {} %", std::round(cpu)));
+            repaint();
+            lastCpu = cpu;
+        }
+    }
 
     std::unique_ptr<jcmp::Label> voiceCount;
     std::unique_ptr<jcmp::Label> cpuLabel;
+    double lastCpu{-2000};
 
     bool isPlayScreenShowing{false};
     bool suppressPowerOff{false};

src/ui/six-sines-editor.cpp

@@ -287,6 +287,10 @@ void SixSinesEditor::idle()
                 applyDawExtraStateFromAudio();
             }
         }
+        else if (aum->action == Synth::AudioToUIMsg::UPDATE_CPU_USAGE)
+        {
+            settingsPanel->setCpuUsage(aum->value);
+        }
         else
         {
             SXSNLOG("Ignored patch message " << aum->action);