From d4f82af20700043f3a21bce785fb8ae64f1a1440 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?S=C3=A9bastien=20Bourdeauducq?= <sb@m-labs.hk>
Date: Thu, 2 Jan 2025 12:26:00 +0800
Subject: [PATCH] phase plot, amplitude control, display pause

---
 sndlock.cpp | 75 ++++++++++++++++++++++++++++++++++-------------------
 1 file changed, 49 insertions(+), 26 deletions(-)

diff --git a/sndlock.cpp b/sndlock.cpp
index f5992f2..df9715e 100644
--- a/sndlock.cpp
+++ b/sndlock.cpp
@@ -24,10 +24,13 @@
 
 static std::atomic<bool> shutdown_threads;
 static std::atomic<double> frequency[SND_PCHAN];
+static std::atomic<double> amplitude[SND_PCHAN];
 static std::atomic<double> lpf_bandwidth[SND_PCHAN];
 
-static std::mutex lpf_hist_mutex;
-static float lpf_hist[SND_PCHAN][512];
+static std::mutex li_hist_mutex;
+static std::atomic<bool> li_hist_pause[SND_PCHAN];
+static float li_hist_mag[SND_PCHAN][512];
+static float li_hist_phase[SND_PCHAN][512];
 
 static void dsp_thread()
 {
@@ -77,7 +80,7 @@ static void dsp_thread()
     for(int i=0;i<SND_PCHAN;i++)
         // input channels are averaged together to reduce uncorrelated noise
         lockin[i].set_scale(pow(0.5, SND_BITS-1)/SND_RCHAN);
-    int lpf_count[SND_PCHAN] = { 0 };
+    int li_count[SND_PCHAN] = { 0 };
 
     nfds_t nfds = sio_nfds(hdl);
     struct pollfd pfd[nfds];
@@ -90,7 +93,6 @@ static void dsp_thread()
             lockin[i].set_bandwidth(lpf_bandwidth[i]/SND_RATE);
 
         if(revents & POLLOUT) {
-            double scale = pow(2.0, SND_BITS-1) - 1.0;
             if(buf_out_offset == sizeof(buf_out)) {
                 for(int i=0;i<SND_PCHAN;i++) {
                     phase_t ftw = frequency_to_ftw(frequency[i]/SND_RATE);
@@ -98,9 +100,11 @@ static void dsp_thread()
                     if(!ftw_fifo[i].push(ftw))
                         std::cerr << "FTW FIFO overflow" << std::endl;
                 }
-                for(int i=0;i<SND_PCHAN;i++)
+                for(int i=0;i<SND_PCHAN;i++) {
+                    double scale = amplitude[i]*(pow(2.0, SND_BITS-1) - 1.0);
                     for(int j=0;j<SND_BUFLEN;j++)
                         buf_out[SND_PCHAN*j+i] = scale*dds[i].get();
+                }
                 buf_out_offset = 0;
             }
             size_t written = sio_write(hdl, (const char *)buf_out + buf_out_offset, sizeof(buf_out) - buf_out_offset);
@@ -125,14 +129,18 @@ static void dsp_thread()
                     double sample = 0.0;
                     for(int k=0;k<SND_RCHAN;k++)
                         sample += (double)buf_in[SND_RCHAN*j+k];
-                    double mag = std::abs(lockin[i].update(sample));
+                    std::complex<double> lockin_out = lockin[i].update(sample);
 
-                    lpf_count[i]++;
-                    if(lpf_count[i] == 200) {
-                        lpf_count[i] = 0;
-                        std::lock_guard<std::mutex> guard(lpf_hist_mutex);
-                        std::memmove(&lpf_hist[i][0], &lpf_hist[i][1], 511*sizeof(float));
-                        lpf_hist[i][511] = mag;
+                    if(!li_hist_pause[i]) {
+                        li_count[i]++;
+                        if(li_count[i] == 200) {
+                            li_count[i] = 0;
+                            std::lock_guard<std::mutex> guard(li_hist_mutex);
+                            std::memmove(&li_hist_mag[i][0], &li_hist_mag[i][1], 511*sizeof(float));
+                            li_hist_mag[i][511] = std::abs(lockin_out);
+                            std::memmove(&li_hist_phase[i][0], &li_hist_phase[i][1], 511*sizeof(float));
+                            li_hist_phase[i][511] = std::arg(lockin_out);
+                        }
                     }
                 }
         }
@@ -157,7 +165,7 @@ int main(int argc, char* argv[])
     std::atexit(glfwTerminate);
     glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
     glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0);
-    static GLFWwindow* window = glfwCreateWindow(1024, 768, "sndlock", nullptr, nullptr);
+    static GLFWwindow* window = glfwCreateWindow(1024, 1200, "sndlock", nullptr, nullptr);
     if(window == nullptr) {
         std::cerr << "failed to create GLFW window" << std::endl;
         return 1;
@@ -185,6 +193,7 @@ int main(int argc, char* argv[])
 
     for(int i=0;i<SND_PCHAN;i++) {
         frequency[i] = 441.0 + 202.0*i;
+        amplitude[i] = 1.0;
         lpf_bandwidth[i] = 10.0;
     }
 
@@ -200,11 +209,10 @@ int main(int argc, char* argv[])
     };
     std::atexit(SetShutdown);
 
-    bool exit = false;
     float plot_scale[SND_PCHAN];
     for(int i=0;i<SND_PCHAN;i++)
-        plot_scale[i] = 0.005f;
-    while(!exit && !glfwWindowShouldClose(window)) {
+        plot_scale[i] = 0.05f;
+    while(!glfwWindowShouldClose(window)) {
         glfwPollEvents();
         glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
         glClear(GL_COLOR_BUFFER_BIT);
@@ -218,37 +226,52 @@ int main(int argc, char* argv[])
         ImGui::PushStyleVar(ImGuiStyleVar_WindowRounding, 0.0f);
         ImGui::Begin("sndlock", nullptr, ImGuiWindowFlags_NoDecoration | ImGuiWindowFlags_NoResize);
 
-        if(ImGui::CollapsingHeader("Modulation", ImGuiTreeNodeFlags_DefaultOpen)) {
+        if(ImGui::CollapsingHeader("Modulation")) {
             for(int i=0;i<SND_PCHAN;i++) {
-                ImGui::Text("Channel %d", i);
                 char str[64];
+                sprintf(str, "Channel %d", i);
+                ImGui::SeparatorText(str);
                 sprintf(str, "frequency##%d", i);
                 float frequency_l = frequency[i];
                 ImGui::SliderFloat(str, &frequency_l, 50.0f, 8000.0f);
                 frequency[i] = frequency_l;
+                sprintf(str, "amplitude##%d", i);
+                float amplitude_l = amplitude[i];
+                ImGui::SliderFloat(str, &amplitude_l, 0.0f, 1.0f);
+                amplitude[i] = amplitude_l;
             }
         }
         if(ImGui::CollapsingHeader("Demodulation", ImGuiTreeNodeFlags_DefaultOpen)) {
             for(int i=0;i<SND_PCHAN;i++) {
                 char str[64];
 
-                ImGui::Text("Channel %d", i);
+                sprintf(str, "Channel %d", i);
+                ImGui::SeparatorText(str);
                 sprintf(str, "LPF BW##%d", i);
                 float lpf_bandwidth_l = lpf_bandwidth[i];
                 ImGui::SliderFloat(str, &lpf_bandwidth_l, 0.5f, 200.0f);
                 lpf_bandwidth[i] = lpf_bandwidth_l;
 
-                sprintf(str, "plot scale##%d", i);
-                ImGui::SliderFloat(str, &plot_scale[i], 0.001f, 0.01f);
-                sprintf(str, "output##%d", i);
+                sprintf(str, "mag scale##%d", i);
+                ImGui::SliderFloat(str, &plot_scale[i], 0.01f, 0.1f);
                 {
-                    std::lock_guard<std::mutex> guard(lpf_hist_mutex);
-                    ImGui::PlotLines(str, lpf_hist[i], 512, 0, 0, -0.0f, plot_scale[i], ImVec2(0.0f, 200.0f));
+                    std::lock_guard<std::mutex> guard(li_hist_mutex);
+                    sprintf(str, "magnitude##%d", i);
+                    ImGui::PlotLines(str, li_hist_mag[i], 512, 0, 0, -0.0f, 0.1f*plot_scale[i], ImVec2(0.0f, 200.0f));
+                    sprintf(str, "phase##%d", i);
+                    ImGui::PlotLines(str, li_hist_phase[i], 512, 0, 0, -M_PI, M_PI, ImVec2(0.0f, 200.0f));
+                }
+                bool pause_l = li_hist_pause[i];
+                sprintf(str, "pause##%d", i);
+                ImGui::Checkbox(str, &pause_l);
+                li_hist_pause[i] = pause_l;
+                ImGui::SameLine();
+                {
+                    std::lock_guard<std::mutex> guard(li_hist_mutex);
+                    ImGui::Text("values: %8.5f %8.5f rad", li_hist_mag[i][511], li_hist_phase[i][511]);
                 }
             }
         }
-        if(ImGui::Button("Exit"))
-            exit = true;
 
         ImGui::End();
         ImGui::PopStyleVar(1);