audio_effect_chorus.h

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/*  audio_effect_chorus.h                                                 */
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/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
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#pragma once

#include "servers/audio/audio_effect.h"

class AudioEffectChorus;

class AudioEffectChorusInstance : public AudioEffectInstance {
	GDCLASS(AudioEffectChorusInstance, AudioEffectInstance);
	friend class AudioEffectChorus;
	Ref<AudioEffectChorus> base;

	Vector<AudioFrame> audio_buffer;
	unsigned int buffer_pos;
	unsigned int buffer_mask;

	AudioFrame filter_h[4];
	uint64_t cycles[4];

	void _process_chunk(const AudioFrame *p_src_frames, AudioFrame *p_dst_frames, int p_frame_count);

public:
	virtual void process(const AudioFrame *p_src_frames, AudioFrame *p_dst_frames, int p_frame_count) override;
};

class AudioEffectChorus : public AudioEffect {
	GDCLASS(AudioEffectChorus, AudioEffect);

	friend class AudioEffectChorusInstance;

public:
	static constexpr int32_t MAX_DELAY_MS = 50;
	static constexpr int32_t MAX_DEPTH_MS = 20;
	static constexpr int32_t MAX_WIDTH_MS = 50;
	static constexpr int32_t MAX_VOICES = 4;
	static constexpr int32_t CYCLES_FRAC = 16;
	static constexpr int32_t CYCLES_MASK = (1 << CYCLES_FRAC) - 1;
	static constexpr int32_t MAX_CHANNELS = 4;
	static constexpr int32_t MS_CUTOFF_MAX = 16000;

private:
	struct Voice {
		float delay;
		float rate;
		float depth;
		float level;
		float cutoff;
		float pan;

		Voice() {
			delay = 12.0;
			rate = 1;
			depth = 0;
			level = 0;
			cutoff = MS_CUTOFF_MAX;
			pan = 0;
		}

	} voice[MAX_VOICES];

	int voice_count;

	float wet;
	float dry;

protected:
	void _validate_property(PropertyInfo &p_property) const;

	static void _bind_methods();

public:
	void set_voice_count(int p_voices);
	int get_voice_count() const;

	void set_voice_delay_ms(int p_voice, float p_delay_ms);
	float get_voice_delay_ms(int p_voice) const;

	void set_voice_rate_hz(int p_voice, float p_rate_hz);
	float get_voice_rate_hz(int p_voice) const;

	void set_voice_depth_ms(int p_voice, float p_depth_ms);
	float get_voice_depth_ms(int p_voice) const;

	void set_voice_level_db(int p_voice, float p_level_db);
	float get_voice_level_db(int p_voice) const;

	void set_voice_cutoff_hz(int p_voice, float p_cutoff_hz);
	float get_voice_cutoff_hz(int p_voice) const;

	void set_voice_pan(int p_voice, float p_pan);
	float get_voice_pan(int p_voice) const;

	void set_wet(float amount);
	float get_wet() const;

	void set_dry(float amount);
	float get_dry() const;

	Ref<AudioEffectInstance> instantiate() override;

	AudioEffectChorus();
};