godot/servers/audio/effects/audio_effect_eq.cpp

#include "audio_effect_eq.h"
#include "servers/audio_server.h"


void AudioEffectEQInstance::process(const AudioFrame *p_src_frames,AudioFrame *p_dst_frames,int p_frame_count) {

	int band_count = bands[0].size();
	EQ::BandProcess *proc_l = bands[0].ptr();
	EQ::BandProcess *proc_r = bands[1].ptr();
	float *bgain = gains.ptr();
	for(int i=0;i<band_count;i++) {
		bgain[i]=Math::db2linear(base->gain[i]);
	}


	for(int i=0;i<p_frame_count;i++) {

		AudioFrame src = p_src_frames[i];
		AudioFrame dst = AudioFrame(0,0);

		for(int j=0;j<band_count;j++) {

			float l = src.l;
			float r = src.r;

			proc_l[j].process_one(l);
			proc_r[j].process_one(r);

			dst.l+=l * bgain[j];
			dst.r+=r * bgain[j];
		}

		p_dst_frames[i]=dst;
	}

}


Ref<AudioEffectInstance> AudioEffectEQ::instance() {
	Ref<AudioEffectEQInstance> ins;
	ins.instance();
	ins->base=Ref<AudioEffectEQ>(this);
	ins->gains.resize(eq.get_band_count());
	for(int i=0;i<2;i++) {
		ins->bands[i].resize(eq.get_band_count());
		for(int j=0;j<ins->bands[i].size();j++) {
			ins->bands[i][j]=eq.get_band_processor(j);
		}
	}

	return ins;
}

void AudioEffectEQ::set_band_gain_db(int p_band,float p_volume) {
	ERR_FAIL_INDEX(p_band,gain.size());
	gain[p_band]=p_volume;
}

float AudioEffectEQ::get_band_gain_db(int p_band) const {
	ERR_FAIL_INDEX_V(p_band,gain.size(),0);

	return gain[p_band];
}
int AudioEffectEQ::get_band_count() const {
	return gain.size();
}

bool AudioEffectEQ::_set(const StringName& p_name, const Variant& p_value) {

	const Map<StringName,int>::Element *E=prop_band_map.find(p_name);
	if (E) {
		set_band_gain_db(E->get(),p_value);
		return true;
	}

	return false;
}

bool AudioEffectEQ::_get(const StringName& p_name,Variant &r_ret) const{

	const Map<StringName,int>::Element *E=prop_band_map.find(p_name);
	if (E) {
		r_ret=get_band_gain_db(E->get());
		return true;
	}

	return false;

}

void AudioEffectEQ::_get_property_list( List<PropertyInfo> *p_list) const{

	for(int i=0;i<band_names.size();i++) {

		p_list->push_back(PropertyInfo(Variant::REAL,band_names[i],PROPERTY_HINT_RANGE,"-60,24,0.1"));
	}
}



void AudioEffectEQ::_bind_methods() {

	ClassDB::bind_method(D_METHOD("set_band_gain_db","band_idx","volume_db"),&AudioEffectEQ::set_band_gain_db);
	ClassDB::bind_method(D_METHOD("get_band_gain_db","band_idx"),&AudioEffectEQ::get_band_gain_db);
	ClassDB::bind_method(D_METHOD("get_band_count"),&AudioEffectEQ::get_band_count);

}

AudioEffectEQ::AudioEffectEQ(EQ::Preset p_preset)
{


	eq.set_mix_rate(AudioServer::get_singleton()->get_mix_rate());
	eq.set_preset_band_mode(p_preset);
	gain.resize(eq.get_band_count());
	for(int i=0;i<gain.size();i++) {
		gain[i]=0.0;
		String name = "band_db/"+itos(eq.get_band_frequency(i))+"_hz";
		prop_band_map[name]=i;
		band_names.push_back(name);
	}
}