ADSR and filters

synth_engine.h

@@ -66,6 +66,22 @@ public:
      */
     float getFrequency() const;
 
+    /**
+     * @brief Configures the ADSR envelope.
+     * @param attack Attack time in seconds.
+     * @param decay Decay time in seconds.
+     * @param sustain Sustain level (0.0 to 1.0).
+     * @param release Release time in seconds.
+     */
+    void setADSR(float attack, float decay, float sustain, float release);
+
+    /**
+     * @brief Configures the filters.
+     * @param lpCutoff Low-pass cutoff frequency in Hz.
+     * @param hpCutoff High-pass cutoff frequency in Hz.
+     */
+    void setFilter(float lpCutoff, float hpCutoff);
+
 private:
     uint32_t _sampleRate;
     uint32_t _phase;      // Phase accumulator for the oscillator.
@@ -73,6 +89,18 @@ private:
     float _volume;
     Waveform _waveform;
     bool _isGateOpen;
+
+    // ADSR State
+    enum EnvState { ENV_IDLE, ENV_ATTACK, ENV_DECAY, ENV_SUSTAIN, ENV_RELEASE };
+    EnvState _envState;
+    float _envLevel;
+    float _attackInc, _decayDec, _sustainLevel, _releaseDec;
+
+    // Filter State
+    float _lpAlpha;
+    float _hpAlpha;
+    float _lpVal;
+    float _hpVal;
 };
 
 #endif // SYNTH_ENGINE_H