significantly improve visual performance

native/src/main.cpp

@@ -139,6 +139,25 @@ Napi::Value SpectrumSetSmoothing(const Napi::CallbackInfo& info) {
     return env.Undefined();
 }
 
+Napi::Value SpectrumPushSamples(const Napi::CallbackInfo& info) {
+    Napi::Env env = info.Env();
+    if (info.Length() < 1 || !info[0].IsTypedArray()) {
+        Napi::TypeError::New(env, "Expected Float32Array").ThrowAsJavaScriptException();
+        return env.Null();
+    }
+    Napi::Float32Array audioData = info[0].As<Napi::Float32Array>();
+    spectrum.pushSamples(audioData.Data(), audioData.ElementLength());
+    return env.Undefined();
+}
+
+Napi::Value SpectrumGetMagnitudes(const Napi::CallbackInfo& info) {
+    Napi::Env env = info.Env();
+    const auto& magnitudes = spectrum.getMagnitudes();
+    Napi::Float32Array result = Napi::Float32Array::New(env, magnitudes.size());
+    memcpy(result.Data(), magnitudes.data(), magnitudes.size() * sizeof(float));
+    return result;
+}
+
 Napi::Value SpectrumProcess(const Napi::CallbackInfo& info) {
     Napi::Env env = info.Env();
     if (info.Length() < 1 || !info[0].IsTypedArray()) {
@@ -280,6 +299,8 @@ Napi::Object Init(Napi::Env env, Napi::Object exports) {
     specExports.Set("getFFTSize", Napi::Function::New(env, SpectrumGetFFTSize));
     specExports.Set("setSampleRate", Napi::Function::New(env, SpectrumSetSampleRate));
     specExports.Set("setSmoothing", Napi::Function::New(env, SpectrumSetSmoothing));
+    specExports.Set("pushSamples", Napi::Function::New(env, SpectrumPushSamples));
+    specExports.Set("getMagnitudes", Napi::Function::New(env, SpectrumGetMagnitudes));
     specExports.Set("process", Napi::Function::New(env, SpectrumProcess));
     specExports.Set("binToFrequency", Napi::Function::New(env, SpectrumBinToFrequency));
     specExports.Set("reset", Napi::Function::New(env, SpectrumReset));

native/src/spectrum.cpp

@@ -55,7 +55,7 @@ void Spectrum::applyWindow(const float* input, float* output, size_t length) {
     }
 }
 
-void Spectrum::pushSamples(const float* input, size_t length) {
+void Spectrum::pushHistory(const float* input, size_t length) {
     if (length == 0 || fftSize_ == 0) {
         return;
     }
@@ -73,13 +73,9 @@ void Spectrum::pushSamples(const float* input, size_t length) {
     bufferedSamples_ = std::min(fftSize_, bufferedSamples_ + length);
 }
 
-const std::vector<float>& Spectrum::process(const float* audioData, size_t length) {
-    if (audioData != nullptr && length > 0) {
-        pushSamples(audioData, length);
-    }
-
+void Spectrum::updateMagnitudes() {
     if (historyBuffer_.empty() || magnitudes_.empty()) {
-        return smoothedMagnitudes_;
+        return;
     }
 
     // Always analyze a full FFT frame from the rolling buffer.
@@ -115,6 +111,21 @@ const std::vector<float>& Spectrum::process(const float* audioData, size_t lengt
             smoothedMagnitudes_[i] = -100.0f;
         }
     }
+}
+
+void Spectrum::pushSamples(const float* input, size_t length) {
+    if (input != nullptr && length > 0) {
+        pushHistory(input, length);
+    }
+    updateMagnitudes();
+}
+
+const std::vector<float>& Spectrum::process(const float* audioData, size_t length) {
+    if (audioData != nullptr && length > 0) {
+        pushHistory(audioData, length);
+    }
+
+    updateMagnitudes();
 
     return smoothedMagnitudes_;
 }

native/src/spectrum.h

@@ -16,6 +16,12 @@ public:
     void setSampleRate(float sampleRate);
     void setSmoothing(float smoothing); // 0.0 - 1.0
 
+    // Feed new samples into the rolling history and update the latest magnitudes.
+    void pushSamples(const float* input, size_t length);
+
+    // Read the latest smoothed magnitudes without mutating analyzer state.
+    const std::vector<float>& getMagnitudes() const { return smoothedMagnitudes_; }
+
     // Process audio and get spectrum data
     // Returns magnitude data (size = fftSize / 2)
     const std::vector<float>& process(const float* audioData, size_t length);
@@ -39,7 +45,8 @@ private:
     size_t bufferedSamples_;
 
     void applyWindow(const float* input, float* output, size_t length);
-    void pushSamples(const float* input, size_t length);
+    void pushHistory(const float* input, size_t length);
+    void updateMagnitudes();
 };
 
 } // namespace Visualizer