Added Audio Limiter bus effect, and sidechain ability to compressor.

servers/audio/effects/audio_effect_compressor.cpp

@@ -19,10 +19,19 @@ void AudioEffectCompressorInstance::process(const AudioFrame *p_src_frames,Audio
 	float mix = base->mix;
 	float gr_meter_decay = exp(1 / (1 * sample_rate));
 
+	const AudioFrame *src = p_src_frames;
+
+	if (base->sidechain!=StringName() && current_channel!=-1) {
+
+		int bus = AudioServer::get_singleton()->thread_find_bus_index(base->sidechain);
+		if (bus>=0) {
+			src = AudioServer::get_singleton()->thread_get_channel_mix_buffer(bus,current_channel);
+		}
+	}
 
 	for(int i=0;i<p_frame_count;i++) {
 
-		AudioFrame s = p_src_frames[i];
+		AudioFrame s = src[i];
 		//convert to positive
 		s.l = Math::abs(s.l);
 		s.r = Math::abs(s.r);
@@ -88,6 +97,7 @@ Ref<AudioEffectInstance> AudioEffectCompressor::instance() {
 	ins->runmax=0;
 	ins->maxover=0;
 	ins->gr_meter=1.0;
+	ins->current_channel=-1;
 	return ins;
 }
 
@@ -147,6 +157,31 @@ float AudioEffectCompressor::get_mix() const {
 	return mix;
 }
 
+void AudioEffectCompressor::set_sidechain(const StringName& p_sidechain) {
+
+	AudioServer::get_singleton()->lock();
+	sidechain=p_sidechain;
+	AudioServer::get_singleton()->unlock();
+}
+
+StringName AudioEffectCompressor::get_sidechain() const {
+
+	return sidechain;
+}
+
+void AudioEffectCompressor::_validate_property(PropertyInfo& property) const {
+
+	if (property.name=="sidechain") {
+
+		String buses="";
+		for(int i=0;i<AudioServer::get_singleton()->get_bus_count();i++) {
+			buses+=",";
+			buses+=AudioServer::get_singleton()->get_bus_name(i);
+		}
+
+		property.hint_string=buses;
+	}
+}
 
 void AudioEffectCompressor::_bind_methods() {
 
@@ -168,12 +203,16 @@ void AudioEffectCompressor::_bind_methods() {
 	ClassDB::bind_method(_MD("set_mix","mix"),&AudioEffectCompressor::set_mix);
 	ClassDB::bind_method(_MD("get_mix"),&AudioEffectCompressor::get_mix);
 
+	ClassDB::bind_method(_MD("set_sidechain","sidechain"),&AudioEffectCompressor::set_sidechain);
+	ClassDB::bind_method(_MD("get_sidechain"),&AudioEffectCompressor::get_sidechain);
+
 	ADD_PROPERTY(PropertyInfo(Variant::REAL,"treshold",PROPERTY_HINT_RANGE,"-60,0,0.1"),_SCS("set_treshold"),_SCS("get_treshold"));
 	ADD_PROPERTY(PropertyInfo(Variant::REAL,"ratio",PROPERTY_HINT_RANGE,"1,48,0.1"),_SCS("set_ratio"),_SCS("get_ratio"));
 	ADD_PROPERTY(PropertyInfo(Variant::REAL,"gain",PROPERTY_HINT_RANGE,"-20,20,0.1"),_SCS("set_gain"),_SCS("get_gain"));
 	ADD_PROPERTY(PropertyInfo(Variant::REAL,"attack_us",PROPERTY_HINT_RANGE,"20,2000,1"),_SCS("set_attack_us"),_SCS("get_attack_us"));
 	ADD_PROPERTY(PropertyInfo(Variant::REAL,"release_ms",PROPERTY_HINT_RANGE,"20,2000,1"),_SCS("set_release_ms"),_SCS("get_release_ms"));
 	ADD_PROPERTY(PropertyInfo(Variant::REAL,"mix",PROPERTY_HINT_RANGE,"0,1,0.01"),_SCS("set_mix"),_SCS("get_mix"));
+	ADD_PROPERTY(PropertyInfo(Variant::REAL,"sidechain",PROPERTY_HINT_ENUM),_SCS("set_sidechain"),_SCS("get_sidechain"));
 
 }
 

servers/audio/effects/audio_effect_compressor.h

@@ -12,8 +12,10 @@ friend class AudioEffectCompressor;
 	Ref<AudioEffectCompressor> base;
 
 	float rundb,averatio,runratio,runmax,maxover,gr_meter;
+	int current_channel;
 public:
 
+	void set_current_channel(int p_channel) { current_channel=p_channel; }
 	virtual void process(const AudioFrame *p_src_frames,AudioFrame *p_dst_frames,int p_frame_count);
 
 };
@@ -29,10 +31,11 @@ friend class AudioEffectCompressorInstance;
 	float attack_us;
 	float release_ms;
 	float mix;
+	StringName sidechain;
 
 
 protected:
-
+	void _validate_property(PropertyInfo& property) const;
 	static void _bind_methods();
 public:
 
@@ -58,6 +61,9 @@ public:
 	void set_mix(float p_mix);
 	float get_mix() const;
 
+	void set_sidechain(const StringName& p_sidechain);
+	StringName get_sidechain() const;
+
 	AudioEffectCompressor();
 };
 

servers/audio/effects/audio_effect_limiter.cpp

@@ -0,0 +1,124 @@
+#include "audio_effect_limiter.h"
+
+void AudioEffectLimiterInstance::process(const AudioFrame *p_src_frames,AudioFrame *p_dst_frames,int p_frame_count) {
+
+	float thresh = Math::db2linear(base->treshold);
+	float threshdb = base->treshold;
+	float ceiling = Math::db2linear(base->ceiling);
+	float ceildb = base->ceiling;
+	float makeup = Math::db2linear(ceildb - threshdb);
+	float makeupdb = ceildb - threshdb;
+	float sc = -base->soft_clip;
+	float scv = Math::db2linear(sc);
+	float sccomp = Math::db2linear(-sc);
+	float peakdb = ceildb + 25;
+	float peaklvl = Math::db2linear(peakdb);
+	float scratio = base->soft_clip_ratio;
+	float scmult = Math::abs((ceildb - sc) / (peakdb - sc));
+
+	for(int i=0;i<p_frame_count;i++) {
+
+		float spl0 = p_src_frames[i].l;
+		float spl1 = p_src_frames[i].r;
+		spl0 = spl0 * makeup;
+		spl1 = spl1 * makeup;
+		float sign0 = (spl0 < 0.0 ? -1.0 : 1.0 );
+		float sign1 = (spl1 < 0.0 ? -1.0 : 1.0 );
+		float abs0 = Math::abs(spl0);
+		float abs1 = Math::abs(spl1);
+		float overdb0 = Math::linear2db(abs0) - ceildb;
+		float overdb1 = Math::linear2db(abs1) - ceildb;
+
+		if (abs0 > scv)
+		{
+			spl0 = sign0 * (scv + Math::db2linear(overdb0 * scmult));
+		}
+		if (abs1 > scv)
+		{
+			spl1 = sign1 * (scv + Math::db2linear(overdb1 * scmult));
+		}
+
+		spl0 = MIN(ceiling, Math::abs(spl0)) * (spl0 < 0.0 ? -1.0 : 1.0);
+		spl1 = MIN(ceiling, Math::abs(spl1)) * (spl1 < 0.0 ? -1.0 : 1.0);
+
+		p_dst_frames[i].l = spl0;
+		p_dst_frames[i].r = spl1;
+	}
+
+}
+
+
+Ref<AudioEffectInstance> AudioEffectLimiter::instance() {
+	Ref<AudioEffectLimiterInstance> ins;
+	ins.instance();
+	ins->base=Ref<AudioEffectLimiter>(this);
+
+	return ins;
+}
+
+
+void AudioEffectLimiter::set_treshold_db(float p_treshold) {
+
+	treshold=p_treshold;
+}
+
+float AudioEffectLimiter::get_treshold_db() const{
+
+	return treshold;
+}
+
+void AudioEffectLimiter::set_ceiling_db(float p_ceiling){
+
+	ceiling=p_ceiling;
+}
+float AudioEffectLimiter::get_ceiling_db() const{
+
+	return ceiling;
+}
+
+void AudioEffectLimiter::set_soft_clip_db(float p_soft_clip){
+
+	soft_clip=p_soft_clip;
+}
+float AudioEffectLimiter::get_soft_clip_db() const{
+
+	return soft_clip;
+}
+
+void AudioEffectLimiter::set_soft_clip_ratio(float p_soft_clip){
+
+	soft_clip_ratio=p_soft_clip;
+}
+float AudioEffectLimiter::get_soft_clip_ratio() const{
+
+	return soft_clip;
+}
+
+
+void AudioEffectLimiter::_bind_methods() {
+
+	ClassDB::bind_method(_MD("set_ceiling_db","ceiling"),&AudioEffectLimiter::set_ceiling_db);
+	ClassDB::bind_method(_MD("get_ceiling_db"),&AudioEffectLimiter::get_ceiling_db);
+
+	ClassDB::bind_method(_MD("set_treshold_db","treshold"),&AudioEffectLimiter::set_treshold_db);
+	ClassDB::bind_method(_MD("get_treshold_db"),&AudioEffectLimiter::get_treshold_db);
+
+	ClassDB::bind_method(_MD("set_soft_clip_db","soft_clip"),&AudioEffectLimiter::set_soft_clip_db);
+	ClassDB::bind_method(_MD("get_soft_clip_db"),&AudioEffectLimiter::get_soft_clip_db);
+
+	ClassDB::bind_method(_MD("set_soft_clip_ratio","soft_clip"),&AudioEffectLimiter::set_soft_clip_ratio);
+	ClassDB::bind_method(_MD("get_soft_clip_ratio"),&AudioEffectLimiter::get_soft_clip_ratio);
+
+	ADD_PROPERTY(PropertyInfo(Variant::REAL,"ceiling_db",PROPERTY_HINT_RANGE,"-20,-0.1,0.1"),_SCS("set_ceiling_db"),_SCS("get_ceiling_db"));
+	ADD_PROPERTY(PropertyInfo(Variant::REAL,"treshold_db",PROPERTY_HINT_RANGE,"-30,0,0.1"),_SCS("set_treshold_db"),_SCS("get_treshold_db"));
+	ADD_PROPERTY(PropertyInfo(Variant::REAL,"soft_clip_db",PROPERTY_HINT_RANGE,"0,6,0.1"),_SCS("set_soft_clip_db"),_SCS("get_soft_clip_db"));
+	ADD_PROPERTY(PropertyInfo(Variant::REAL,"soft_clip_ratio",PROPERTY_HINT_RANGE,"3,20,0.1"),_SCS("set_soft_clip_ratio"),_SCS("get_soft_clip_ratio"));
+}
+
+AudioEffectLimiter::AudioEffectLimiter()
+{
+	treshold=0;
+	ceiling=-0.1;
+	soft_clip=2;
+	soft_clip_ratio=10;
+}

servers/audio/effects/audio_effect_limiter.h

@@ -0,0 +1,58 @@
+#ifndef AUDIO_EFFECT_LIMITER_H
+#define AUDIO_EFFECT_LIMITER_H
+
+
+#include "servers/audio/audio_effect.h"
+
+class AudioEffectLimiter;
+
+class AudioEffectLimiterInstance : public AudioEffectInstance {
+	GDCLASS(AudioEffectLimiterInstance,AudioEffectInstance)
+friend class AudioEffectLimiter;
+	Ref<AudioEffectLimiter> base;
+
+	float mix_volume_db;
+public:
+
+	virtual void process(const AudioFrame *p_src_frames,AudioFrame *p_dst_frames,int p_frame_count);
+
+};
+
+
+class AudioEffectLimiter : public AudioEffect {
+	GDCLASS(AudioEffectLimiter,AudioEffect)
+
+friend class AudioEffectLimiterInstance;
+	float treshold;
+	float ceiling;
+	float soft_clip;
+	float soft_clip_ratio;
+
+protected:
+
+	static void _bind_methods();
+public:
+
+
+	void set_treshold_db(float p_treshold);
+	float get_treshold_db() const;
+
+	void set_ceiling_db(float p_ceiling);
+	float get_ceiling_db() const;
+
+	void set_soft_clip_db(float p_soft_clip);
+	float get_soft_clip_db() const;
+
+	void set_soft_clip_ratio(float p_soft_clip);
+	float get_soft_clip_ratio() const;
+
+
+	Ref<AudioEffectInstance> instance();
+	void set_volume_db(float p_volume);
+	float get_volume_db() const;
+
+	AudioEffectLimiter();
+};
+
+
+#endif // AUDIO_EFFECT_LIMITER_H

servers/audio_server.cpp

@@ -29,6 +29,8 @@
 #include "audio_server.h"
 #include "globals.h"
 #include "os/os.h"
+#include "servers/audio/effects/audio_effect_compressor.h"
+
 AudioDriver *AudioDriver::singleton=NULL;
 AudioDriver *AudioDriver::get_singleton() {
 
@@ -514,7 +516,12 @@ void AudioServer::_update_bus_effects(int p_bus) {
 	for(int i=0;i<buses[p_bus]->channels.size();i++) {
 		buses[p_bus]->channels[i].effect_instances.resize(buses[p_bus]->effects.size());
 		for(int j=0;j<buses[p_bus]->effects.size();j++) {
-			buses[p_bus]->channels[i].effect_instances[j]=buses[p_bus]->effects[j].effect->instance();
+			Ref<AudioEffectInstance> fx = buses[p_bus]->effects[j].effect->instance();
+			if (fx->cast_to<AudioEffectCompressorInstance>()) {
+				fx->cast_to<AudioEffectCompressorInstance>()->set_current_channel(i);
+			}
+			buses[p_bus]->channels[i].effect_instances[j]=fx;
+
 		}
 	}
 }

servers/register_server_types.cpp

@@ -47,6 +47,7 @@
 #include "audio/effects/audio_effect_chorus.h"
 #include "audio/effects/audio_effect_delay.h"
 #include "audio/effects/audio_effect_compressor.h"
+#include "audio/effects/audio_effect_limiter.h"
 
 static void _debugger_get_resource_usage(List<ScriptDebuggerRemote::ResourceUsage>* r_usage) {
 
@@ -109,6 +110,7 @@ void register_server_types() {
 		ClassDB::register_class<AudioEffectChorus>();
 		ClassDB::register_class<AudioEffectDelay>();
 		ClassDB::register_class<AudioEffectCompressor>();
+		ClassDB::register_class<AudioEffectLimiter>();
 	}