[3.x] Backport panning strength parameters from 4.0

core/project_settings.cpp

@@ -1085,6 +1085,10 @@ ProjectSettings::ProjectSettings() {
 
 	GLOBAL_DEF("audio/default_bus_layout", "res://default_bus_layout.tres");
 	custom_prop_info["audio/default_bus_layout"] = PropertyInfo(Variant::STRING, "audio/default_bus_layout", PROPERTY_HINT_FILE, "*.tres");
+	GLOBAL_DEF_RST("audio/2d_panning_strength", 1.0f);
+	custom_prop_info["audio/2d_panning_strength"] = PropertyInfo(Variant::REAL, "audio/2d_panning_strength", PROPERTY_HINT_RANGE, "0,4,0.01");
+	GLOBAL_DEF_RST("audio/3d_panning_strength", 1.0f);
+	custom_prop_info["audio/3d_panning_strength"] = PropertyInfo(Variant::REAL, "audio/3d_panning_strength", PROPERTY_HINT_RANGE, "0,4,0.01");
 
 	PoolStringArray extensions = PoolStringArray();
 	extensions.push_back("gd");

doc/classes/AudioStreamPlayer2D.xml

@@ -62,6 +62,9 @@
 		<member name="max_distance" type="float" setter="set_max_distance" getter="get_max_distance" default="2000.0">
 			Maximum distance from which audio is still hearable.
 		</member>
+		<member name="panning_strength" type="float" setter="set_panning_strength" getter="get_panning_strength" default="1.0">
+			Scales the panning strength for this node by multiplying the base [member ProjectSettings.audio/2d_panning_strength] with this factor. Higher values will pan audio from left to right more dramatically than lower values.
+		</member>
 		<member name="pitch_scale" type="float" setter="set_pitch_scale" getter="get_pitch_scale" default="1.0">
 			The pitch and the tempo of the audio, as a multiplier of the audio sample's sample rate.
 		</member>

doc/classes/AudioStreamPlayer3D.xml

@@ -88,6 +88,9 @@
 		<member name="out_of_range_mode" type="int" setter="set_out_of_range_mode" getter="get_out_of_range_mode" enum="AudioStreamPlayer3D.OutOfRangeMode" default="0">
 			Decides if audio should pause when source is outside of [member max_distance] range.
 		</member>
+		<member name="panning_strength" type="float" setter="set_panning_strength" getter="get_panning_strength" default="1.0">
+			Scales the panning strength for this node by multiplying the base [member ProjectSettings.audio/3d_panning_strength] with this factor. Higher values will pan audio from left to right more dramatically than lower values.
+		</member>
 		<member name="pitch_scale" type="float" setter="set_pitch_scale" getter="get_pitch_scale" default="1.0">
 			The pitch and the tempo of the audio, as a multiplier of the audio sample's sample rate.
 		</member>

doc/classes/ProjectSettings.xml

@@ -259,6 +259,12 @@
 		<member name="application/run/main_scene" type="String" setter="" getter="" default="&quot;&quot;">
 			Path to the main scene file that will be loaded when the project runs.
 		</member>
+		<member name="audio/2d_panning_strength" type="float" setter="" getter="" default="1.0">
+			The base strength of the panning effect for all AudioStreamPlayer2D nodes. The panning strength can be further scaled on each Node using [member AudioStreamPlayer2D.panning_strength].
+		</member>
+		<member name="audio/3d_panning_strength" type="float" setter="" getter="" default="1.0">
+			The base strength of the panning effect for all AudioStreamPlayer3D nodes. The panning strength can be further scaled on each Node using [member AudioStreamPlayer3D.panning_strength].
+		</member>
 		<member name="audio/channel_disable_threshold_db" type="float" setter="" getter="" default="-60.0">
 			Audio buses will disable automatically when sound goes below a given dB threshold for a given time. This saves CPU as effects assigned to that bus will no longer do any processing.
 		</member>

scene/2d/audio_stream_player_2d.cpp

@@ -31,6 +31,7 @@
 #include "audio_stream_player_2d.h"
 
 #include "core/engine.h"
+#include "core/project_settings.h"
 #include "scene/2d/area_2d.h"
 #include "scene/2d/listener_2d.h"
 #include "scene/main/viewport.h"
@@ -232,7 +233,14 @@ void AudioStreamPlayer2D::_notification(int p_what) {
 					float multiplier = Math::pow(1.0f - dist / max_distance, attenuation);
 					multiplier *= Math::db2linear(volume_db); //also apply player volume!
 
-					float pan = CLAMP((relative_to_listener.x + screen_size.x * 0.5) / screen_size.x, 0.0, 1.0);
+					float pan = relative_to_listener.x / screen_size.x;
+					// Don't let the panning effect extend (too far) beyond the screen.
+					pan = CLAMP(pan, -1, 1);
+
+					// Bake in a constant factor here to allow the project setting defaults for 2d and 3d to be normalized to 1.0.
+					pan *= panning_strength * cached_global_panning_strength * 0.5f;
+
+					pan = CLAMP(pan + 0.5, 0.0, 1.0);
 
 					float l = 1.0 - pan;
 					float r = pan;
@@ -458,6 +466,15 @@ Ref<AudioStreamPlayback> AudioStreamPlayer2D::get_stream_playback() {
 	return stream_playback;
 }
 
+void AudioStreamPlayer2D::set_panning_strength(float p_panning_strength) {
+	ERR_FAIL_COND_MSG(p_panning_strength < 0, "Panning strength must be a positive number.");
+	panning_strength = p_panning_strength;
+}
+
+float AudioStreamPlayer2D::get_panning_strength() const {
+	return panning_strength;
+}
+
 void AudioStreamPlayer2D::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_stream", "stream"), &AudioStreamPlayer2D::set_stream);
 	ClassDB::bind_method(D_METHOD("get_stream"), &AudioStreamPlayer2D::get_stream);
@@ -496,6 +513,9 @@ void AudioStreamPlayer2D::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_stream_paused", "pause"), &AudioStreamPlayer2D::set_stream_paused);
 	ClassDB::bind_method(D_METHOD("get_stream_paused"), &AudioStreamPlayer2D::get_stream_paused);
 
+	ClassDB::bind_method(D_METHOD("set_panning_strength", "panning_strength"), &AudioStreamPlayer2D::set_panning_strength);
+	ClassDB::bind_method(D_METHOD("get_panning_strength"), &AudioStreamPlayer2D::get_panning_strength);
+
 	ClassDB::bind_method(D_METHOD("get_stream_playback"), &AudioStreamPlayer2D::get_stream_playback);
 
 	ClassDB::bind_method(D_METHOD("_bus_layout_changed"), &AudioStreamPlayer2D::_bus_layout_changed);
@@ -508,6 +528,7 @@ void AudioStreamPlayer2D::_bind_methods() {
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "stream_paused", PROPERTY_HINT_NONE, ""), "set_stream_paused", "get_stream_paused");
 	ADD_PROPERTY(PropertyInfo(Variant::REAL, "max_distance", PROPERTY_HINT_EXP_RANGE, "1,4096,1,or_greater"), "set_max_distance", "get_max_distance");
 	ADD_PROPERTY(PropertyInfo(Variant::REAL, "attenuation", PROPERTY_HINT_EXP_EASING, "attenuation"), "set_attenuation", "get_attenuation");
+	ADD_PROPERTY(PropertyInfo(Variant::REAL, "panning_strength", PROPERTY_HINT_RANGE, "0,3,0.01,or_greater"), "set_panning_strength", "get_panning_strength");
 	ADD_PROPERTY(PropertyInfo(Variant::STRING, "bus", PROPERTY_HINT_ENUM, ""), "set_bus", "get_bus");
 	ADD_PROPERTY(PropertyInfo(Variant::INT, "area_mask", PROPERTY_HINT_LAYERS_2D_PHYSICS), "set_area_mask", "get_area_mask");
 
@@ -528,6 +549,7 @@ AudioStreamPlayer2D::AudioStreamPlayer2D() {
 	stream_paused_fade_in = false;
 	stream_paused_fade_out = false;
 	AudioServer::get_singleton()->connect("bus_layout_changed", this, "_bus_layout_changed");
+	cached_global_panning_strength = ProjectSettings::get_singleton()->get("audio/2d_panning_strength");
 }
 
 AudioStreamPlayer2D::~AudioStreamPlayer2D() {

scene/2d/audio_stream_player_2d.h

@@ -89,6 +89,9 @@ private:
 	float max_distance;
 	float attenuation;
 
+	float panning_strength = 1.0f;
+	float cached_global_panning_strength = 1.0f;
+
 protected:
 	void _validate_property(PropertyInfo &property) const;
 	void _notification(int p_what);
@@ -122,6 +125,9 @@ public:
 	void set_attenuation(float p_curve);
 	float get_attenuation() const;
 
+	void set_panning_strength(float p_panning_strength);
+	float get_panning_strength() const;
+
 	void set_area_mask(uint32_t p_mask);
 	uint32_t get_area_mask() const;
 

scene/3d/audio_stream_player_3d.cpp

@@ -30,6 +30,7 @@
 
 #include "audio_stream_player_3d.h"
 #include "core/engine.h"
+#include "core/project_settings.h"
 #include "scene/3d/area.h"
 #include "scene/3d/camera.h"
 #include "scene/3d/listener.h"
@@ -471,9 +472,10 @@ void AudioStreamPlayer3D::_notification(int p_what) {
 
 				output.filter_gain = Math::db2linear(db_att);
 
-				//TODO: The lower the second parameter (tightness) the more the sound will "enclose" the listener (more undirected / playing from
+				// Bake in a constant factor here to allow the project setting defaults for 2d and 3d to be normalized to 1.0.
-				//      speakers not facing the source) - this could be made distance dependent.
+				float tightness = cached_global_panning_strength * 2.0f;
-				_calc_output_vol(local_pos.normalized(), 4.0, output);
+				tightness *= panning_strength;
+				_calc_output_vol(local_pos.normalized(), tightness, output);
 
 				unsigned int cc = AudioServer::get_singleton()->get_channel_count();
 				for (unsigned int k = 0; k < cc; k++) {
@@ -898,6 +900,15 @@ Ref<AudioStreamPlayback> AudioStreamPlayer3D::get_stream_playback() {
 	return stream_playback;
 }
 
+void AudioStreamPlayer3D::set_panning_strength(float p_panning_strength) {
+	ERR_FAIL_COND_MSG(p_panning_strength < 0, "Panning strength must be a positive number.");
+	panning_strength = p_panning_strength;
+}
+
+float AudioStreamPlayer3D::get_panning_strength() const {
+	return panning_strength;
+}
+
 void AudioStreamPlayer3D::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_stream", "stream"), &AudioStreamPlayer3D::set_stream);
 	ClassDB::bind_method(D_METHOD("get_stream"), &AudioStreamPlayer3D::get_stream);
@@ -963,6 +974,9 @@ void AudioStreamPlayer3D::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_stream_paused", "pause"), &AudioStreamPlayer3D::set_stream_paused);
 	ClassDB::bind_method(D_METHOD("get_stream_paused"), &AudioStreamPlayer3D::get_stream_paused);
 
+	ClassDB::bind_method(D_METHOD("set_panning_strength", "panning_strength"), &AudioStreamPlayer3D::set_panning_strength);
+	ClassDB::bind_method(D_METHOD("get_panning_strength"), &AudioStreamPlayer3D::get_panning_strength);
+
 	ClassDB::bind_method(D_METHOD("get_stream_playback"), &AudioStreamPlayer3D::get_stream_playback);
 
 	ClassDB::bind_method(D_METHOD("_bus_layout_changed"), &AudioStreamPlayer3D::_bus_layout_changed);
@@ -978,6 +992,7 @@ void AudioStreamPlayer3D::_bind_methods() {
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "stream_paused", PROPERTY_HINT_NONE, ""), "set_stream_paused", "get_stream_paused");
 	ADD_PROPERTY(PropertyInfo(Variant::REAL, "max_distance", PROPERTY_HINT_RANGE, "0,4096,0.01,or_greater"), "set_max_distance", "get_max_distance");
 	ADD_PROPERTY(PropertyInfo(Variant::INT, "out_of_range_mode", PROPERTY_HINT_ENUM, "Mix,Pause"), "set_out_of_range_mode", "get_out_of_range_mode");
+	ADD_PROPERTY(PropertyInfo(Variant::REAL, "panning_strength", PROPERTY_HINT_RANGE, "0,3,0.01,or_greater"), "set_panning_strength", "get_panning_strength");
 	ADD_PROPERTY(PropertyInfo(Variant::STRING, "bus", PROPERTY_HINT_ENUM, ""), "set_bus", "get_bus");
 	ADD_PROPERTY(PropertyInfo(Variant::INT, "area_mask", PROPERTY_HINT_LAYERS_2D_PHYSICS), "set_area_mask", "get_area_mask");
 	ADD_GROUP("Emission Angle", "emission_angle");
@@ -1031,6 +1046,7 @@ AudioStreamPlayer3D::AudioStreamPlayer3D() {
 	velocity_tracker.instance();
 	AudioServer::get_singleton()->connect("bus_layout_changed", this, "_bus_layout_changed");
 	set_disable_scale(true);
+	cached_global_panning_strength = ProjectSettings::get_singleton()->get("audio/3d_panning_strength");
 }
 AudioStreamPlayer3D::~AudioStreamPlayer3D() {
 }

scene/3d/audio_stream_player_3d.h

@@ -141,6 +141,9 @@ private:
 
 	float _get_attenuation_db(float p_distance) const;
 
+	float panning_strength = 1.0f;
+	float cached_global_panning_strength = 1.0f;
+
 protected:
 	void _validate_property(PropertyInfo &property) const;
 	void _notification(int p_what);
@@ -207,6 +210,9 @@ public:
 	void set_stream_paused(bool p_pause);
 	bool get_stream_paused() const;
 
+	void set_panning_strength(float p_panning_strength);
+	float get_panning_strength() const;
+
 	Ref<AudioStreamPlayback> get_stream_playback();
 
 	AudioStreamPlayer3D();