From 52d33fa3c5016fa5e485150ef18ea171f3eca379 Mon Sep 17 00:00:00 2001
From: Stefano D'Angelo <stefano.dangelo@orastron.com>
Date: Thu, 21 Sep 2023 07:59:41 +0200
Subject: [PATCH] finalized bw_noise_gen + updated synth(pp)_mono + better
 bw_gain debug

---
 TODO                                          |   4 +-
 .../synth_mono/src/bw_example_synth_mono.c    |   2 +
 .../src/bw_example_synthpp_mono.cpp           |   2 +
 include/bw_gain.h                             |   1 +
 include/bw_noise_gen.h                        | 302 +++++++++++++++---
 5 files changed, 270 insertions(+), 41 deletions(-)

diff --git a/TODO b/TODO
index bed6c55..df95d75 100644
--- a/TODO
+++ b/TODO
@@ -4,7 +4,7 @@
 in progress:
 * add initial state (x0) to reset state of all modules
 * check assumptions w.r.t. usage of math functions
-* empty functions etc. to keep consistency and forward compatibility?
+* empty functions etc. to keep consistency and forward compatibility
 * format declarations in a more readable way
 code:
  general:
@@ -13,8 +13,6 @@ code:
 * common smoothing policy (as control rate as possible?) - smoothing control?
 * IMPLEMENTATION prepocessor def???
  semi-specific:
-* osc post filter (and one pole init, slew rate, etc.) val from input? set state instead?
-* audio rate optional pulse width/slope inputs?
 * max_delay -> set sample rate? see reverb
  specific:
 * bw_comb: should also modulate feedback?
diff --git a/examples/synth_mono/src/bw_example_synth_mono.c b/examples/synth_mono/src/bw_example_synth_mono.c
index 929cebb..7546839 100644
--- a/examples/synth_mono/src/bw_example_synth_mono.c
+++ b/examples/synth_mono/src/bw_example_synth_mono.c
@@ -53,6 +53,7 @@ void bw_example_synth_mono_init(bw_example_synth_mono *instance) {
 	bw_osc_tri_set_antialiasing(&instance->vco2_tri_coeffs, 1);
 	bw_osc_pulse_set_antialiasing(&instance->vco3_pulse_coeffs, 1);
 	bw_osc_tri_set_antialiasing(&instance->vco3_tri_coeffs, 1);
+	bw_noise_gen_set_sample_rate_scaling(&instance->noise_gen_coeffs, 1);
 	bw_phase_gen_set_frequency(&instance->a440_phase_gen_coeffs, 440.f);
 	
 	instance->rand_state = 0xbaddecaf600dfeed;
@@ -83,6 +84,7 @@ void bw_example_synth_mono_set_sample_rate(bw_example_synth_mono *instance, floa
 	bw_ppm_set_sample_rate(&instance->ppm_coeffs, sample_rate);
 
 	bw_osc_saw_reset_coeffs(&instance->vco_saw_coeffs);
+	bw_noise_gen_reset_coeffs(&instance->noise_gen_coeffs);
 }
 
 void bw_example_synth_mono_reset(bw_example_synth_mono *instance) {
diff --git a/examples/synthpp_mono/src/bw_example_synthpp_mono.cpp b/examples/synthpp_mono/src/bw_example_synthpp_mono.cpp
index bbc8ed9..4d8c686 100644
--- a/examples/synthpp_mono/src/bw_example_synthpp_mono.cpp
+++ b/examples/synthpp_mono/src/bw_example_synthpp_mono.cpp
@@ -33,6 +33,7 @@ void bw_example_synthpp_mono_init(bw_example_synthpp_mono *instance) {
 	instance->vco3OscSaw.setAntialiasing(true);
 	instance->vco3OscPulse.setAntialiasing(true);
 	instance->vco3OscTri.setAntialiasing(true);
+	instance->noiseGen.setSampleRateScaling(true);
 	instance->a440PhaseGen.setFrequency(440.f);
 
 	instance->rand_state = 0xbaddecaf600dfeed;
@@ -86,6 +87,7 @@ void bw_example_synthpp_mono_reset(bw_example_synthpp_mono *instance) {
 	instance->vco3OscTri.reset();
 	instance->vco3Gain.reset();
 	instance->oscFilt.reset();
+	instance->noiseGen.reset();
 	instance->pinkFilt.reset();
 	instance->noiseGain.reset();
 	instance->vcfEnvGen.reset();
diff --git a/include/bw_gain.h b/include/bw_gain.h
index 462b9d2..cf04e0f 100644
--- a/include/bw_gain.h
+++ b/include/bw_gain.h
@@ -461,6 +461,7 @@ static inline float bw_gain_get_gain_cur(
 		const bw_gain_coeffs * BW_RESTRICT coeffs) {
 	BW_ASSERT(coeffs != NULL);
 	BW_ASSERT_DEEP(bw_gain_coeffs_is_valid(coeffs));
+	BW_ASSERT_DEEP(coeffs->state >= bw_gain_coeffs_state_reset_coeffs);
 
 	return bw_one_pole_get_y_z1(&coeffs->smooth_state);
 }
diff --git a/include/bw_noise_gen.h b/include/bw_noise_gen.h
index 0c12201..ecf7807 100644
--- a/include/bw_noise_gen.h
+++ b/include/bw_noise_gen.h
@@ -33,6 +33,9 @@
  *    <ul>
  *      <li>Version <strong>1.0.0</strong>:
  *        <ul>
+ *          <li>Added <code>bw_noise_gen_reset_coeffs()</code>,
+ *              <code>bw_noise_gen_update_coeffs_ctrl()</code>,
+ *              and <code>bw_noise_gen_update_coeffs_audio()</code>.</li>
  *          <li><code>bw_noise_gen_process()</code> and
  *              <code>bw_noise_gen_process_multi()</code> now use
  *              <code>size_t</code> to count samples and channels.</li>
@@ -42,6 +45,7 @@
  *          <li>Added overloaded C++ <code>process()</code> function taking
  *              C-style arrays as arguments.</li>
  *          <li>Removed usage of reserved identifiers.</li>
+ *          <li>Added debugging code.</li>
  *        </ul>
  *      </li>
  *      <li>Version <strong>0.6.0</strong>:
@@ -87,44 +91,84 @@ typedef struct bw_noise_gen_coeffs bw_noise_gen_coeffs;
  *
  *    #### bw_noise_gen_init()
  *  ```>>> */
-static inline void bw_noise_gen_init(bw_noise_gen_coeffs *BW_RESTRICT coeffs, uint64_t *BW_RESTRICT state);
+static inline void bw_noise_gen_init(
+	bw_noise_gen_coeffs * BW_RESTRICT coeffs,
+	uint64_t * BW_RESTRICT            state);
 /*! <<<```
  *    Initializes input parameter values and sets the `state` pointer to obtain
  *    pseudo-random numbers in `coeffs`.
  *
  *    #### bw_noise_gen_set_sample_rate()
  *  ```>>> */
-static inline void bw_noise_gen_set_sample_rate(bw_noise_gen_coeffs *BW_RESTRICT coeffs, float sample_rate);
+static inline void bw_noise_gen_set_sample_rate(
+	bw_noise_gen_coeffs * BW_RESTRICT coeffs,
+	float                             sample_rate);
 /*! <<<```
  *    Sets the `sample_rate` (Hz) value in `coeffs`.
  *
+ *    #### bw_noise_gen_reset_coeffs()
+ *  ```>>> */
+static inline void bw_noise_gen_reset_coeffs(
+	bw_noise_gen_coeffs * BW_RESTRICT coeffs);
+/*! <<<```
+ *    Resets coefficients in `coeffs` to assume their target values.
+ *
+ *    #### bw_noise_gen_update_coeffs_ctrl()
+ *  ```>>> */
+static inline void bw_noise_gen_update_coeffs_ctrl(
+	bw_noise_gen_coeffs * BW_RESTRICT coeffs);
+/*! <<<```
+ *    Triggers control-rate update of coefficients in `coeffs`.
+ *
+ *    #### bw_noise_gen_update_coeffs_audio()
+ *  ```>>> */
+static inline void bw_noise_gen_update_coeffs_audio(
+	bw_noise_gen_coeffs * BW_RESTRICT coeffs);
+/*! <<<```
+ *    Triggers audio-rate update of coefficients in `coeffs`.
+ *
  *    #### bw_noise_gen_process1\*()
  *  ```>>> */
-static inline float bw_noise_gen_process1(const bw_noise_gen_coeffs *BW_RESTRICT coeffs);
-static inline float bw_noise_gen_process1_scaling(const bw_noise_gen_coeffs *BW_RESTRICT coeffs);
+static inline float bw_noise_gen_process1(
+	const bw_noise_gen_coeffs * BW_RESTRICT coeffs);
+
+static inline float bw_noise_gen_process1_scaling(
+	const bw_noise_gen_coeffs * BW_RESTRICT coeffs);
 /*! <<<```
  *    These functions generate and return one sample using `coeffs`, where:
  *     * `bw_noise_gen_process1()` assumes that sample rate scaling is disabled;
  *     * `bw_noise_gen_process1_scaling()` assumes that sample rate scaling is
  *       enabled.
  *
+ *    Whether sample rate scaling is enabled or not is unchecked even for
+ *    debugging purposes.
+ *
  *    #### bw_noise_gen_process()
  *  ```>>> */
-static inline void bw_noise_gen_process(bw_noise_gen_coeffs *BW_RESTRICT coeffs, float *BW_RESTRICT y, size_t n_samples);
+static inline void bw_noise_gen_process(
+	bw_noise_gen_coeffs * BW_RESTRICT coeffs,
+	float * BW_RESTRICT               y,
+	size_t                            n_samples);
 /*! <<<```
  *    Generates and fills the first `n_samples` of the output buffer `y` using
  *    `coeffs`.
  *
  *    #### bw_noise_gen_process_multi()
  *  ```>>> */
-static inline void bw_noise_gen_process_multi(bw_noise_gen_coeffs *BW_RESTRICT coeffs, float *BW_RESTRICT const *BW_RESTRICT y, size_t n_channels, size_t n_samples);
+static inline void bw_noise_gen_process_multi(
+	bw_noise_gen_coeffs * BW_RESTRICT       coeffs,
+	float * BW_RESTRICT const * BW_RESTRICT y,
+	size_t                                  n_channels,
+	size_t                                  n_samples);
 /*! <<<```
  *    Generates and fills the first `n_samples` of the `n_channels` output
  *    buffers `y` using `coeffs`.
  *
  *    #### bw_noise_gen_set_sample_rate_scaling()
  *  ```>>> */
-static inline void bw_noise_gen_set_sample_rate_scaling(bw_noise_gen_coeffs *BW_RESTRICT coeffs, char value);
+static inline void bw_noise_gen_set_sample_rate_scaling(
+	bw_noise_gen_coeffs * BW_RESTRICT coeffs,
+	char                              value);
 /*! <<<```
  *    Sets whether the output should be scaled (`value` non-`0`) or not (`0`)
  *    according to the sample rate in `coeffs`.
@@ -138,10 +182,23 @@ static inline void bw_noise_gen_set_sample_rate_scaling(bw_noise_gen_coeffs *BW_
  *
  *    #### bw_noise_gen_get_scaling_k()
  *  ```>>> */
-static inline float bw_noise_gen_get_scaling_k(const bw_noise_gen_coeffs *BW_RESTRICT coeffs);
+static inline float bw_noise_gen_get_scaling_k(
+	const bw_noise_gen_coeffs * BW_RESTRICT coeffs);
 /*! <<<```
  *    Returns the sample rate scaling factor that is applied or would be applied
  *    if sample rate scaling were enabled, as stored in `coeffs`.
+ *
+ *    #### bw_noise_gen_coeffs_is_valid()
+ *  ```>>> */
+static inline char bw_noise_gen_coeffs_is_valid(
+	const bw_noise_gen_coeffs * BW_RESTRICT coeffs);
+/*! <<<```
+ *    Tries to determine whether `coeffs` is valid and returns non-`0` if it
+ *    seems to be the case and `0` if it is certainly not. False positives are
+ *    possible, false negatives are not.
+ *
+ *    `coeffs` must at least point to a readable memory block of size greater
+ *    than or equal to that of `bw_noise_gen_coeffs`.
  *  }}} */
 
 #ifdef __cplusplus
@@ -160,54 +217,208 @@ static inline float bw_noise_gen_get_scaling_k(const bw_noise_gen_coeffs *BW_RES
 extern "C" {
 #endif
 
+#ifdef BW_DEBUG_DEEP
+enum bw_noise_gen_coeffs_state {
+	bw_noise_gen_coeffs_state_invalid,
+	bw_noise_gen_coeffs_state_init,
+	bw_noise_gen_coeffs_state_set_sample_rate,
+	bw_noise_gen_coeffs_state_reset_coeffs
+};
+#endif
+
 struct bw_noise_gen_coeffs {
+#ifdef BW_DEBUG_DEEP
+	uint32_t			hash;
+	enum bw_noise_gen_coeffs_state	state;
+#endif
+
 	// Coefficients
-	float		 scaling_k;
+	float				scaling_k;
 
 	// Parameters
-	uint64_t	*BW_RESTRICT state;
-	char		 sample_rate_scaling;
+	uint64_t * BW_RESTRICT		rand_state;
+	char				sample_rate_scaling;
 };
 
-static inline void bw_noise_gen_init(bw_noise_gen_coeffs *BW_RESTRICT coeffs, uint64_t *BW_RESTRICT state) {
-	coeffs->state = state;
+static inline void bw_noise_gen_init(
+		bw_noise_gen_coeffs * BW_RESTRICT coeffs,
+		uint64_t * BW_RESTRICT            state) {
+	BW_ASSERT(coeffs != NULL);
+	BW_ASSERT(state != NULL);
+
+	coeffs->rand_state = state;
 	coeffs->sample_rate_scaling = 0;
+
+#ifdef BW_DEBUG_DEEP
+	coeffs->hash = bw_hash_sdbm("bw_noise_gen_coeffs");
+	coeffs->state = bw_noise_gen_coeffs_state_init;
+#endif
+	BW_ASSERT_DEEP(bw_noise_gen_coeffs_is_valid(coeffs));
+	BW_ASSERT_DEEP(coeffs->state == bw_noise_gen_coeffs_state_init);
 }
 
-static inline void bw_noise_gen_set_sample_rate(bw_noise_gen_coeffs *BW_RESTRICT coeffs, float sample_rate) {
+static inline void bw_noise_gen_set_sample_rate(
+		bw_noise_gen_coeffs * BW_RESTRICT coeffs,
+		float                             sample_rate) {
+	BW_ASSERT(coeffs != NULL);
+	BW_ASSERT_DEEP(bw_noise_gen_coeffs_is_valid(coeffs));
+	BW_ASSERT_DEEP(coeffs->state >= bw_noise_gen_coeffs_state_init);
+	BW_ASSERT(bw_is_finite(sample_rate) && sample_rate > 0.f);
+
 	coeffs->scaling_k = 0.004761904761904762f * bw_sqrtf(sample_rate);
+
+#ifdef BW_DEBUG_DEEP
+	coeffs->state = bw_noise_gen_coeffs_state_set_sample_rate;
+#endif
+	BW_ASSERT_DEEP(bw_noise_gen_coeffs_is_valid(coeffs));
+	BW_ASSERT_DEEP(coeffs->state == bw_noise_gen_coeffs_state_set_sample_rate);
 }
 
-static inline float bw_noise_gen_process1(const bw_noise_gen_coeffs *BW_RESTRICT coeffs) {
-	return bw_randf(coeffs->state);
+static inline void bw_noise_gen_reset_coeffs(
+		bw_noise_gen_coeffs * BW_RESTRICT coeffs) {
+	BW_ASSERT(coeffs != NULL);
+	BW_ASSERT_DEEP(bw_noise_gen_coeffs_is_valid(coeffs));
+	BW_ASSERT_DEEP(coeffs->state >= bw_noise_gen_coeffs_state_set_sample_rate);
+
+	(void)coeffs;
+
+#ifdef BW_DEBUG_DEEP
+	coeffs->state = bw_noise_gen_coeffs_state_reset_coeffs;
+#endif
+	BW_ASSERT_DEEP(bw_noise_gen_coeffs_is_valid(coeffs));
+	BW_ASSERT_DEEP(coeffs->state == bw_noise_gen_coeffs_state_reset_coeffs);
 }
 
-static inline float bw_noise_gen_process1_scaling(const bw_noise_gen_coeffs *BW_RESTRICT coeffs) {
-	return coeffs->scaling_k * bw_randf(coeffs->state);
+static inline void bw_noise_gen_update_coeffs_ctrl(
+		bw_noise_gen_coeffs * BW_RESTRICT coeffs) {
+	BW_ASSERT(coeffs != NULL);
+	BW_ASSERT_DEEP(bw_noise_gen_coeffs_is_valid(coeffs));
+	BW_ASSERT_DEEP(coeffs->state >= bw_noise_gen_coeffs_state_reset_coeffs);
+
+	(void)coeffs;
 }
 
-static inline void bw_noise_gen_process(bw_noise_gen_coeffs *BW_RESTRICT coeffs, float *BW_RESTRICT y, size_t n_samples) {
+static inline void bw_noise_gen_update_coeffs_audio(
+		bw_noise_gen_coeffs * BW_RESTRICT coeffs) {
+	BW_ASSERT(coeffs != NULL);
+	BW_ASSERT_DEEP(bw_noise_gen_coeffs_is_valid(coeffs));
+	BW_ASSERT_DEEP(coeffs->state >= bw_noise_gen_coeffs_state_reset_coeffs);
+
+	(void)coeffs;
+}
+
+static inline float bw_noise_gen_process1(
+		const bw_noise_gen_coeffs * BW_RESTRICT coeffs) {
+	BW_ASSERT(coeffs != NULL);
+	BW_ASSERT_DEEP(bw_noise_gen_coeffs_is_valid(coeffs));
+	BW_ASSERT_DEEP(coeffs->state >= bw_noise_gen_coeffs_state_reset_coeffs);
+
+	const float y = bw_randf(coeffs->rand_state);
+
+	BW_ASSERT_DEEP(bw_noise_gen_coeffs_is_valid(coeffs));
+	BW_ASSERT_DEEP(coeffs->state >= bw_noise_gen_coeffs_state_reset_coeffs);
+	BW_ASSERT(bw_is_finite(y));
+
+	return y;
+}
+
+static inline float bw_noise_gen_process1_scaling(
+		const bw_noise_gen_coeffs * BW_RESTRICT coeffs) {
+	BW_ASSERT(coeffs != NULL);
+	BW_ASSERT_DEEP(bw_noise_gen_coeffs_is_valid(coeffs));
+	BW_ASSERT_DEEP(coeffs->state >= bw_noise_gen_coeffs_state_reset_coeffs);
+
+	const float y = coeffs->scaling_k * bw_randf(coeffs->rand_state);
+
+	BW_ASSERT_DEEP(bw_noise_gen_coeffs_is_valid(coeffs));
+	BW_ASSERT_DEEP(coeffs->state >= bw_noise_gen_coeffs_state_reset_coeffs);
+	BW_ASSERT(bw_is_finite(y));
+
+	return y;
+}
+
+static inline void bw_noise_gen_process(
+		bw_noise_gen_coeffs * BW_RESTRICT coeffs,
+		float * BW_RESTRICT               y,
+		size_t                            n_samples) {
+	BW_ASSERT(coeffs != NULL);
+	BW_ASSERT_DEEP(bw_noise_gen_coeffs_is_valid(coeffs));
+	BW_ASSERT_DEEP(coeffs->state >= bw_noise_gen_coeffs_state_reset_coeffs);
+	BW_ASSERT(y != NULL);
+
 	if (coeffs->sample_rate_scaling)
 		for (size_t i = 0; i < n_samples; i++)
 			y[i] = bw_noise_gen_process1(coeffs);
 	else
 		for (size_t i = 0; i < n_samples; i++)
 			y[i] = bw_noise_gen_process1_scaling(coeffs);
+
+	BW_ASSERT_DEEP(bw_noise_gen_coeffs_is_valid(coeffs));
+	BW_ASSERT_DEEP(coeffs->state >= bw_noise_gen_coeffs_state_reset_coeffs);
+	BW_ASSERT_DEEP(bw_has_only_finite(y, n_samples));
 }
 
-static inline void bw_noise_gen_process_multi(bw_noise_gen_coeffs *BW_RESTRICT coeffs, float *BW_RESTRICT const *BW_RESTRICT y, size_t n_channels, size_t n_samples) {
+static inline void bw_noise_gen_process_multi(
+		bw_noise_gen_coeffs * BW_RESTRICT       coeffs,
+		float * BW_RESTRICT const * BW_RESTRICT y,
+		size_t                                  n_channels,
+		size_t                                  n_samples) {
+	BW_ASSERT(coeffs != NULL);
+	BW_ASSERT_DEEP(bw_noise_gen_coeffs_is_valid(coeffs));
+	BW_ASSERT_DEEP(coeffs->state >= bw_noise_gen_coeffs_state_reset_coeffs);
+	BW_ASSERT(y != NULL);
+
 	for (size_t i = 0; i < n_channels; i++)
 		bw_noise_gen_process(coeffs, y[i], n_samples);
+
+	BW_ASSERT_DEEP(bw_noise_gen_coeffs_is_valid(coeffs));
+	BW_ASSERT_DEEP(coeffs->state >= bw_noise_gen_coeffs_state_reset_coeffs);
 }
 
-static inline void bw_noise_gen_set_sample_rate_scaling(bw_noise_gen_coeffs *BW_RESTRICT coeffs, char value) {
+static inline void bw_noise_gen_set_sample_rate_scaling(
+		bw_noise_gen_coeffs * BW_RESTRICT coeffs,
+		char                              value) {
+	BW_ASSERT(coeffs != NULL);
+	BW_ASSERT_DEEP(bw_noise_gen_coeffs_is_valid(coeffs));
+	BW_ASSERT_DEEP(coeffs->state >= bw_noise_gen_coeffs_state_init);
+
 	coeffs->sample_rate_scaling = value;
+
+	BW_ASSERT_DEEP(bw_noise_gen_coeffs_is_valid(coeffs));
+	BW_ASSERT_DEEP(coeffs->state >= bw_noise_gen_coeffs_state_init);
 }
 
-static inline float bw_noise_gen_get_scaling_k(const bw_noise_gen_coeffs *BW_RESTRICT coeffs) {
+static inline float bw_noise_gen_get_scaling_k(
+		const bw_noise_gen_coeffs * BW_RESTRICT coeffs) {
+	BW_ASSERT(coeffs != NULL);
+	BW_ASSERT_DEEP(bw_noise_gen_coeffs_is_valid(coeffs));
+	BW_ASSERT_DEEP(coeffs->state >= bw_noise_gen_coeffs_state_set_sample_rate);
+
 	return coeffs->scaling_k;
 }
 
+static inline char bw_noise_gen_coeffs_is_valid(
+		const bw_noise_gen_coeffs * BW_RESTRICT coeffs) {
+	BW_ASSERT(coeffs != NULL);
+
+#ifdef BW_DEBUG_DEEP
+	if (coeffs->hash != bw_hash_sdbm("bw_noise_gen_coeffs"))
+		return 0;
+	if (coeffs->state < bw_noise_gen_coeffs_state_init || coeffs->state > bw_noise_gen_coeffs_state_reset_coeffs)
+		return 0;
+#endif
+
+	if (coeffs->rand_state == NULL)
+		return 0;
+
+#ifdef BW_DEBUG_DEEP
+	if (coeffs->state >= bw_noise_gen_coeffs_state_set_sample_rate && coeffs->scaling_k <= 0.f)
+		return 0;
+#endif
+
+	return 1;
+}
+
 #ifdef __cplusplus
 }
 
@@ -223,17 +434,24 @@ namespace Brickworks {
 template<size_t N_CHANNELS>
 class NoiseGen {
 public:
-	NoiseGen(uint64_t *BW_RESTRICT state);
+	NoiseGen(
+		uint64_t * BW_RESTRICT state);
 
-	void setSampleRate(float sampleRate);
-	void process(
-		float *BW_RESTRICT const *BW_RESTRICT y,
-		size_t nSamples);
-	void process(
-		std::array<float *BW_RESTRICT, N_CHANNELS> y,
-		size_t nSamples);
+	void setSampleRate(
+		float sampleRate);
 
-	void setSampleRateScaling(bool value);
+	void reset();
+
+	void process(
+		float * BW_RESTRICT const * BW_RESTRICT y,
+		size_t                                  nSamples);
+
+	void process(
+		std::array<float * BW_RESTRICT, N_CHANNELS> y,
+		size_t                                      nSamples);
+
+	void setSampleRateScaling(
+		bool value);
 	
 	float getScalingK();
 /*! <<<...
@@ -247,35 +465,43 @@ public:
  * change at any time in future versions. Please, do not use it directly. */
 
 private:
-	bw_noise_gen_coeffs	 coeffs;
+	bw_noise_gen_coeffs	coeffs;
 };
 
 template<size_t N_CHANNELS>
-inline NoiseGen<N_CHANNELS>::NoiseGen(uint64_t *BW_RESTRICT state) {
+inline NoiseGen<N_CHANNELS>::NoiseGen(
+		uint64_t * BW_RESTRICT state) {
 	bw_noise_gen_init(&coeffs, state);
 }
 
 template<size_t N_CHANNELS>
-inline void NoiseGen<N_CHANNELS>::setSampleRate(float sampleRate) {
+inline void NoiseGen<N_CHANNELS>::setSampleRate(
+		float sampleRate) {
 	bw_noise_gen_set_sample_rate(&coeffs, sampleRate);
 }
 
+template<size_t N_CHANNELS>
+inline void NoiseGen<N_CHANNELS>::reset() {
+	bw_noise_gen_reset_coeffs(&coeffs);
+}
+
 template<size_t N_CHANNELS>
 inline void NoiseGen<N_CHANNELS>::process(
 		float *BW_RESTRICT const *BW_RESTRICT y,
-		size_t nSamples) {
+		size_t                                nSamples) {
 	bw_noise_gen_process_multi(&coeffs, y, N_CHANNELS, nSamples);
 }
 
 template<size_t N_CHANNELS>
 inline void NoiseGen<N_CHANNELS>::process(
-		std::array<float *BW_RESTRICT, N_CHANNELS> y,
-		size_t nSamples) {
+		std::array<float * BW_RESTRICT, N_CHANNELS> y,
+		size_t                                      nSamples) {
 	process(y.data(), nSamples);
 }
 
 template<size_t N_CHANNELS>
-inline void NoiseGen<N_CHANNELS>::setSampleRateScaling(bool value) {
+inline void NoiseGen<N_CHANNELS>::setSampleRateScaling(
+		bool value) {
 	bw_noise_gen_set_sample_rate_scaling(&coeffs, value);
 }