/*************************************************************************/
/*  spatial_sound_server_sw.cpp                                          */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
/*                      https://godotengine.org                          */
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/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur.                 */
/* Copyright (c) 2014-2017 Godot Engine contributors (cf. AUTHORS.md)    */
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/* permit persons to whom the Software is furnished to do so, subject to */
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/* included in all copies or substantial portions of the Software.       */
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/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
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/*************************************************************************/
#include "spatial_sound_server_sw.h"
#include "os/os.h"
#include "servers/audio/audio_filter_sw.h"

int SpatialSoundServerSW::InternalAudioStream::get_channel_count() const {

	return AudioServer::get_singleton()->get_default_channel_count();
}

void SpatialSoundServerSW::InternalAudioStream::set_mix_rate(int p_rate) {
}

void SpatialSoundServerSW::InternalAudioStream::update() {

	owner->_update_sources();
}

bool SpatialSoundServerSW::InternalAudioStream::mix(int32_t *p_buffer, int p_frames) {

	return owner->internal_buffer_mix(p_buffer, p_frames);
}

void SpatialSoundServerSW::_update_sources() {

	_THREAD_SAFE_METHOD_
	for (Set<Source *>::Element *E = streaming_sources.front(); E; E = E->next()) {

		Source *s = E->get();
		ERR_CONTINUE(!s->stream);
		s->stream->update();
	}
}

SpatialSoundServerSW::Room::Room() {

	//	params[ROOM_PARAM_SPEED_OF_SOUND]=343.0;
	params[ROOM_PARAM_SPEED_OF_SOUND_SCALE] = 1;
	params[ROOM_PARAM_DOPPLER_FACTOR] = 1.0;
	params[ROOM_PARAM_PITCH_SCALE] = 1.0;
	params[ROOM_PARAM_VOLUME_SCALE_DB] = 0;
	params[ROOM_PARAM_REVERB_SEND] = 0;
	params[ROOM_PARAM_CHORUS_SEND] = 0;
	params[ROOM_PARAM_ATTENUATION_SCALE] = 1.0;
	params[ROOM_PARAM_ATTENUATION_HF_CUTOFF] = 5000;
	params[ROOM_PARAM_ATTENUATION_HF_FLOOR_DB] = -24.0;
	params[ROOM_PARAM_ATTENUATION_HF_RATIO_EXP] = 1.0;
	params[ROOM_PARAM_ATTENUATION_REVERB_SCALE] = 0.0;
	override_other_sources = false;
	reverb = ROOM_REVERB_HALL;
	octree_id = 0;
	level = -1;
}

SpatialSoundServerSW::Source::Source() {

	params[SOURCE_PARAM_VOLUME_DB] = 0.0;
	params[SOURCE_PARAM_PITCH_SCALE] = 1.0;
	params[SOURCE_PARAM_ATTENUATION_MIN_DISTANCE] = 1;
	params[SOURCE_PARAM_ATTENUATION_MAX_DISTANCE] = 100;
	params[SOURCE_PARAM_ATTENUATION_DISTANCE_EXP] = 1.0; //linear (and not really good)
	params[SOURCE_PARAM_EMISSION_CONE_DEGREES] = 180.0; //cone disabled
	params[SOURCE_PARAM_EMISSION_CONE_ATTENUATION_DB] = -6.0; //minus 6 db attenuation
	stream = NULL;
	voices.resize(1);
	last_voice = 0;
}

SpatialSoundServerSW::Source::Voice::Voice() {

	active = false;
	restart = false;
	priority = 0;
	pitch_scale = 1.0;
	volume_scale = 0.0;
	voice_rid = AudioServer::get_singleton()->voice_create();
}
SpatialSoundServerSW::Source::Voice::~Voice() {

	AudioServer::get_singleton()->free(voice_rid);
}

SpatialSoundServerSW::Listener::Listener() {

	params[LISTENER_PARAM_VOLUME_SCALE_DB] = 0.0;
	params[LISTENER_PARAM_PITCH_SCALE] = 1.0;
	params[LISTENER_PARAM_ATTENUATION_SCALE] = 1.0;
	params[LISTENER_PARAM_RECEPTION_CONE_DEGREES] = 60.0;
	params[LISTENER_PARAM_RECEPTION_CONE_ATTENUATION_DB] = -6; // minus six decibels
}

/* SPACE */
RID SpatialSoundServerSW::space_create() {

	Space *space = memnew(Space);
	RID space_rid = space_owner.make_rid(space);
	space->default_room = room_create();
	room_set_space(space->default_room, space_rid);
	return space_rid;
}

/* ROOM */

RID SpatialSoundServerSW::room_create() {

	Room *room = memnew(Room);
	return room_owner.make_rid(room);
}

void SpatialSoundServerSW::room_set_space(RID p_room, RID p_space) {

	Room *room = room_owner.get(p_room);
	ERR_FAIL_COND(!room);

	if (room->space.is_valid()) {

		Space *space = space_owner.get(room->space);
		space->rooms.erase(p_room);
		space->octree.erase(room->octree_id);
		//room->octree_id=0;
	}

	room->space = RID();

	if (p_space.is_valid()) {

		Space *space = space_owner.get(p_space);
		ERR_FAIL_COND(!space);
		space->rooms.insert(p_room);
		room->octree_id = space->octree.create(room, AABB());
		//set bounds
		AABB aabb = room->bounds.is_empty() ? AABB() : room->bounds.get_aabb();
		space->octree.move(room->octree_id, room->transform.xform(aabb));
		room->space = p_space;
	}
}

RID SpatialSoundServerSW::room_get_space(RID p_room) const {

	Room *room = room_owner.get(p_room);
	ERR_FAIL_COND_V(!room, RID());

	return room->space;
}

void SpatialSoundServerSW::room_set_bounds(RID p_room, const BSP_Tree &p_bounds) {

	Room *room = room_owner.get(p_room);
	ERR_FAIL_COND(!room);

	room->bounds = p_bounds;

	if (!room->space.is_valid())
		return;

	AABB aabb = room->bounds.is_empty() ? AABB() : room->bounds.get_aabb();
	Space *space = space_owner.get(room->space);
	ERR_FAIL_COND(!space);

	space->octree.move(room->octree_id, room->transform.xform(aabb));
}
BSP_Tree SpatialSoundServerSW::room_get_bounds(RID p_room) const {
	Room *room = room_owner.get(p_room);
	ERR_FAIL_COND_V(!room, BSP_Tree());

	return room->bounds;
}

void SpatialSoundServerSW::room_set_transform(RID p_room, const Transform &p_transform) {

	if (space_owner.owns(p_room))
		p_room = space_owner.get(p_room)->default_room;

	Room *room = room_owner.get(p_room);
	ERR_FAIL_COND(!room);
	room->transform = p_transform;
	room->inverse_transform = p_transform.affine_inverse(); // needs to be done to unscale BSP properly

	if (!room->space.is_valid())
		return;

	if (!room->bounds.is_empty()) {

		Space *space = space_owner.get(room->space);
		ERR_FAIL_COND(!space);

		space->octree.move(room->octree_id, room->transform.xform(room->bounds.get_aabb()));
	}
}

Transform SpatialSoundServerSW::room_get_transform(RID p_room) const {

	if (space_owner.owns(p_room))
		p_room = space_owner.get(p_room)->default_room;

	Room *room = room_owner.get(p_room);
	ERR_FAIL_COND_V(!room, Transform());
	return room->transform;
}

void SpatialSoundServerSW::room_set_param(RID p_room, RoomParam p_param, float p_value) {

	if (space_owner.owns(p_room))
		p_room = space_owner.get(p_room)->default_room;

	ERR_FAIL_INDEX(p_param, ROOM_PARAM_MAX);
	Room *room = room_owner.get(p_room);
	ERR_FAIL_COND(!room);
	room->params[p_param] = p_value;
}
float SpatialSoundServerSW::room_get_param(RID p_room, RoomParam p_param) const {

	if (space_owner.owns(p_room))
		p_room = space_owner.get(p_room)->default_room;

	ERR_FAIL_INDEX_V(p_param, ROOM_PARAM_MAX, 0);
	Room *room = room_owner.get(p_room);
	ERR_FAIL_COND_V(!room, 0);
	return room->params[p_param];
}

void SpatialSoundServerSW::room_set_level(RID p_room, int p_level) {

	Room *room = room_owner.get(p_room);
	ERR_FAIL_COND(!room);
	room->level = p_level;
}

int SpatialSoundServerSW::room_get_level(RID p_room) const {

	Room *room = room_owner.get(p_room);
	ERR_FAIL_COND_V(!room, 0);
	return room->level;
}

void SpatialSoundServerSW::room_set_reverb(RID p_room, RoomReverb p_reverb) {

	if (space_owner.owns(p_room))
		p_room = space_owner.get(p_room)->default_room;

	Room *room = room_owner.get(p_room);
	ERR_FAIL_COND(!room);
	room->reverb = p_reverb;
}
SpatialSoundServerSW::RoomReverb SpatialSoundServerSW::room_get_reverb(RID p_room) const {

	if (space_owner.owns(p_room))
		p_room = space_owner.get(p_room)->default_room;

	Room *room = room_owner.get(p_room);
	ERR_FAIL_COND_V(!room, ROOM_REVERB_SMALL);
	return room->reverb;
}

//useful for underwater or rooms with very strange conditions
void SpatialSoundServerSW::room_set_force_params_to_all_sources(RID p_room, bool p_force) {

	if (space_owner.owns(p_room))
		p_room = space_owner.get(p_room)->default_room;

	Room *room = room_owner.get(p_room);
	ERR_FAIL_COND(!room);
	room->override_other_sources = p_force;
}
bool SpatialSoundServerSW::room_is_forcing_params_to_all_sources(RID p_room) const {

	if (space_owner.owns(p_room))
		p_room = space_owner.get(p_room)->default_room;

	Room *room = room_owner.get(p_room);
	ERR_FAIL_COND_V(!room, false);
	return room->override_other_sources;
}

/* SOURCE */

RID SpatialSoundServerSW::source_create(RID p_space) {

	Space *space = space_owner.get(p_space);
	ERR_FAIL_COND_V(!space, RID());

	Source *source = memnew(Source);
	source->space = p_space;
	RID source_rid = source_owner.make_rid(source);
	space->sources.insert(source_rid);

	return source_rid;
}

void SpatialSoundServerSW::source_set_polyphony(RID p_source, int p_voice_count) {

	ERR_FAIL_COND(p_voice_count <= 0); // more than 32 is too much, change this if you really need more
	if (p_voice_count > 32) {

		ERR_PRINT("Voices will be clipped to 32");
		p_voice_count = 32;
	}
	Source *source = source_owner.get(p_source);
	ERR_FAIL_COND(!source);

	if (p_voice_count < source->voices.size()) {

		for (int i = p_voice_count; i < source->voices.size(); i++) {
			active_voices.erase(ActiveVoice(source, i)); //erase from active voices
		}
	}
	source->voices.resize(p_voice_count);
}

int SpatialSoundServerSW::source_get_polyphony(RID p_source) const {

	Source *source = source_owner.get(p_source);
	ERR_FAIL_COND_V(!source, -1);
	return source->voices.size();
}

void SpatialSoundServerSW::source_set_transform(RID p_source, const Transform &p_transform) {

	Source *source = source_owner.get(p_source);
	ERR_FAIL_COND(!source);
	source->transform = p_transform;
	source->transform.orthonormalize();
}
Transform SpatialSoundServerSW::source_get_transform(RID p_source) const {

	Source *source = source_owner.get(p_source);
	ERR_FAIL_COND_V(!source, Transform());
	return source->transform;
}

void SpatialSoundServerSW::source_set_param(RID p_source, SourceParam p_param, float p_value) {

	ERR_FAIL_INDEX(p_param, SOURCE_PARAM_MAX);
	Source *source = source_owner.get(p_source);
	ERR_FAIL_COND(!source);
	source->params[p_param] = p_value;
}
float SpatialSoundServerSW::source_get_param(RID p_source, SourceParam p_param) const {
	ERR_FAIL_INDEX_V(p_param, SOURCE_PARAM_MAX, 0);
	Source *source = source_owner.get(p_source);
	ERR_FAIL_COND_V(!source, 0);
	return source->params[p_param];
}

void SpatialSoundServerSW::source_set_audio_stream(RID p_source, AudioServer::AudioStream *p_stream) {

	Source *source = source_owner.get(p_source);
	ERR_FAIL_COND(!source);
	AudioServer::get_singleton()->lock();
	source->stream = p_stream;
	_THREAD_SAFE_METHOD_

	if (!p_stream) {
		streaming_sources.erase(source);
		active_voices.erase(ActiveVoice(source, VOICE_IS_STREAM));
	} else {
		streaming_sources.insert(source);
		active_voices.insert(ActiveVoice(source, VOICE_IS_STREAM));
		zeromem(source->stream_data.filter_state, sizeof(Source::StreamData::FilterState) * 4); //reset filter for safetyness
		p_stream->set_mix_rate(AudioServer::get_singleton()->get_default_mix_rate());
	}

	AudioServer::get_singleton()->unlock();

} //null to unset

SpatialSoundServer::SourceVoiceID SpatialSoundServerSW::source_play_sample(RID p_source, RID p_sample, int p_mix_rate, int p_voice, int p_priority) {

	Source *source = source_owner.get(p_source);
	ERR_FAIL_COND_V(!source, SOURCE_INVALID_VOICE);

	int to_play = 0;

	if (p_voice == SOURCE_NEXT_VOICE) {
		const int num_voices = source->voices.size();
		bool free_found = false;
		int lowest_priority_voice = -1;
		int lowest_priority = 0x7FFFFFFF;
		for (int i = 0; i < num_voices; i++) {
			const int candidate = (source->last_voice + 1 + i) % num_voices;
			const Source::Voice &v = source->voices[candidate];
			if (!v.active && !v.restart) {
				free_found = true;
				to_play = candidate;
				break;
			}
			if (v.priority < lowest_priority) {
				lowest_priority = v.priority;
				lowest_priority_voice = candidate;
			}
		}
		if (!free_found)
			to_play = lowest_priority_voice;
	} else
		to_play = p_voice;

	ERR_FAIL_INDEX_V(to_play, source->voices.size(), SOURCE_INVALID_VOICE);

	if ((source->voices[to_play].active || source->voices[to_play].restart) && source->voices[to_play].priority > p_priority)
		return SOURCE_INVALID_VOICE;

	source->voices[to_play].restart = true;
	source->voices[to_play].priority = p_priority;
	source->voices[to_play].sample_rid = p_sample;
	source->voices[to_play].sample_mix_rate = p_mix_rate;
	source->voices[to_play].pitch_scale = 1;
	source->voices[to_play].volume_scale = 0;
	source->last_voice = to_play;
	active_voices.insert(ActiveVoice(source, to_play));
	return to_play;
}

/* VOICES */
void SpatialSoundServerSW::source_voice_set_pitch_scale(RID p_source, SourceVoiceID p_voice, float p_pitch_scale) {

	Source *source = source_owner.get(p_source);
	ERR_FAIL_COND(!source);
	ERR_FAIL_INDEX(p_voice, source->voices.size());
	source->voices[p_voice].pitch_scale = p_pitch_scale;
}
void SpatialSoundServerSW::source_voice_set_volume_scale_db(RID p_source, SourceVoiceID p_voice, float p_db) {

	Source *source = source_owner.get(p_source);
	ERR_FAIL_COND(!source);
	ERR_FAIL_INDEX(p_voice, source->voices.size());
	source->voices[p_voice].volume_scale = p_db;
}

bool SpatialSoundServerSW::source_is_voice_active(RID p_source, SourceVoiceID p_voice) const {

	Source *source = source_owner.get(p_source);
	ERR_FAIL_COND_V(!source, false);
	ERR_FAIL_INDEX_V(p_voice, source->voices.size(), false);
	return source->voices[p_voice].active || source->voices[p_voice].restart;
}
void SpatialSoundServerSW::source_stop_voice(RID p_source, SourceVoiceID p_voice) {

	Source *source = source_owner.get(p_source);
	ERR_FAIL_COND(!source);
	ERR_FAIL_INDEX(p_voice, source->voices.size());
	if (source->voices[p_voice].active) {
		AudioServer::get_singleton()->voice_stop(source->voices[p_voice].voice_rid);
	}
	source->voices[p_voice].active = false;
	source->voices[p_voice].restart = false;
	active_voices.erase(ActiveVoice(source, p_voice));
}

/* LISTENER */

RID SpatialSoundServerSW::listener_create() {

	Listener *listener = memnew(Listener);
	RID listener_rid = listener_owner.make_rid(listener);
	return listener_rid;
}

void SpatialSoundServerSW::listener_set_space(RID p_listener, RID p_space) {

	Listener *listener = listener_owner.get(p_listener);
	ERR_FAIL_COND(!listener);

	if (listener->space.is_valid()) {

		Space *lspace = space_owner.get(listener->space);
		ERR_FAIL_COND(!lspace);
		lspace->listeners.erase(p_listener);
	}

	listener->space = RID();

	if (p_space.is_valid()) {
		Space *space = space_owner.get(p_space);
		ERR_FAIL_COND(!space);

		listener->space = p_space;
		space->listeners.insert(p_listener);
	}
}

void SpatialSoundServerSW::listener_set_transform(RID p_listener, const Transform &p_transform) {

	Listener *listener = listener_owner.get(p_listener);
	ERR_FAIL_COND(!listener);
	listener->transform = p_transform;
	listener->transform.orthonormalize(); //must be done..
}
Transform SpatialSoundServerSW::listener_get_transform(RID p_listener) const {

	Listener *listener = listener_owner.get(p_listener);
	ERR_FAIL_COND_V(!listener, Transform());
	return listener->transform;
}

void SpatialSoundServerSW::listener_set_param(RID p_listener, ListenerParam p_param, float p_value) {

	ERR_FAIL_INDEX(p_param, LISTENER_PARAM_MAX);
	Listener *listener = listener_owner.get(p_listener);
	ERR_FAIL_COND(!listener);
	listener->params[p_param] = p_value;
}

float SpatialSoundServerSW::listener_get_param(RID p_listener, ListenerParam p_param) const {

	ERR_FAIL_INDEX_V(p_param, LISTENER_PARAM_MAX, 0);
	Listener *listener = listener_owner.get(p_listener);
	ERR_FAIL_COND_V(!listener, 0);
	return listener->params[p_param];
}

/* MISC */

void SpatialSoundServerSW::free(RID p_id) {

	if (space_owner.owns(p_id)) {

		Space *space = space_owner.get(p_id);
		free(space->default_room);

		while (space->listeners.size()) {
			listener_set_space(space->listeners.front()->get(), RID());
		}
		while (space->sources.size()) {
			free(space->sources.front()->get());
		}
		while (space->rooms.size()) {
			room_set_space(space->rooms.front()->get(), RID());
		}
		space_owner.free(p_id);
		memdelete(space);

	} else if (source_owner.owns(p_id)) {

		Source *source = source_owner.get(p_id);
		if (source->stream)
			source_set_audio_stream(p_id, NULL);

		Space *space = space_owner.get(source->space);
		ERR_FAIL_COND(!space);
		space->sources.erase(p_id);
		for (int i = 0; i < source->voices.size(); i++) {
			active_voices.erase(ActiveVoice(source, i));
		}
		source_owner.free(p_id);
		memdelete(source);
	} else if (listener_owner.owns(p_id)) {

		Listener *listener = listener_owner.get(p_id);
		if (listener->space.is_valid()) {
			Space *space = space_owner.get(listener->space);
			ERR_FAIL_COND(!space);
			space->listeners.erase(p_id);
		}
		listener_owner.free(p_id);
		memdelete(listener);

	} else if (room_owner.owns(p_id)) {

		Room *room = room_owner.get(p_id);

		if (room->space.is_valid()) {
			Space *space = space_owner.get(room->space);
			ERR_FAIL_COND(!space);
			space->octree.erase(room->octree_id);
			space->rooms.erase(p_id);
		}
		room_owner.free(p_id);
		memdelete(room);
	} else {
		ERR_PRINT("Attempt to free invalid ID");
	}
}

void SpatialSoundServerSW::_clean_up_owner(RID_OwnerBase *p_owner, const char *p_area) {

	List<RID> rids;
	p_owner->get_owned_list(&rids);

	for (List<RID>::Element *I = rids.front(); I; I = I->next()) {
		if (OS::get_singleton()->is_stdout_verbose()) {

			print_line("Leaked RID (" + itos(I->get().get_id()) + ") of type " + String(p_area));
		}
		free(I->get());
	}
}

void SpatialSoundServerSW::init() {

	internal_buffer = memnew_arr(int32_t, INTERNAL_BUFFER_SIZE * INTERNAL_BUFFER_MAX_CHANNELS);
	internal_buffer_channels = AudioServer::get_singleton()->get_default_channel_count();

	internal_audio_stream = memnew(InternalAudioStream);
	internal_audio_stream->owner = this;
	internal_audio_stream_rid = AudioServer::get_singleton()->audio_stream_create(internal_audio_stream);

	AudioServer::get_singleton()->stream_set_active(internal_audio_stream_rid, true);
}

static float _get_attenuation(float cosine, float angle, float attenuation) {

	float listener_ang = Math::rad2deg(Math::acos(cosine)) - angle;

	if (listener_ang > 0 && angle < 180.0) {
		listener_ang /= (180.0 - angle);
		return Math::db2linear(Math::sin(listener_ang * (Math_PI / 2.0)) * attenuation);
	}
	return 1.0;
}

bool SpatialSoundServerSW::internal_buffer_mix(int32_t *p_buffer, int p_frames) {

	if (streaming_sources.size() == 0)
		return false; //nothing to mix

	for (Set<Source *>::Element *E = streaming_sources.front(); E; E = E->next()) {

		Source *s = E->get();
		ERR_CONTINUE(!s->stream);

		int channels = s->stream->get_channel_count();
		Source::StreamData &sd = s->stream_data;

		int todo = p_frames;

		AudioFilterSW filter;
		filter.set_sampling_rate(AudioServer::get_singleton()->get_default_mix_rate());
		filter.set_cutoff(sd.filter_cutoff);
		filter.set_gain(sd.filter_gain);
		filter.set_resonance(1);
		filter.set_mode(AudioFilterSW::HIGHSHELF);
		filter.set_stages(1);
		AudioFilterSW::Coeffs coefs;
		filter.prepare_coefficients(&coefs);

		int32_t in[4];
#ifndef SPATIAL_SOUND_SERVER_NO_FILTER
#define DO_FILTER(m_c)                                                                                                                                                                        \
	{                                                                                                                                                                                         \
		float val = in[m_c];                                                                                                                                                                  \
		float pre = val;                                                                                                                                                                      \
		val = val * coefs.b0 + sd.filter_state[m_c].hb[0] * coefs.b1 + sd.filter_state[m_c].hb[1] * coefs.b2 + sd.filter_state[m_c].ha[0] * coefs.a1 + sd.filter_state[m_c].ha[1] * coefs.a2; \
		sd.filter_state[m_c].ha[1] = sd.filter_state[m_c].ha[0];                                                                                                                              \
		sd.filter_state[m_c].hb[1] = sd.filter_state[m_c].hb[0];                                                                                                                              \
		sd.filter_state[m_c].hb[0] = pre;                                                                                                                                                     \
		sd.filter_state[m_c].ha[0] = val;                                                                                                                                                     \
		in[m_c] = Math::fast_ftoi(val);                                                                                                                                                       \
	}
#else
#define DO_FILTER(m_c)
#endif

		while (todo) {

			int to_mix = MIN(todo, INTERNAL_BUFFER_SIZE);

			s->stream->mix(internal_buffer, to_mix);

			switch (internal_buffer_channels) {

				case 2: {

					float p = sd.panning.x * 0.5 + 0.5;
					float panf[2] = { (1.0 - p), p };
					panf[0] *= sd.volume;
					panf[1] *= sd.volume;

					int32_t pan[2] = { Math::fast_ftoi(panf[0] * (1 << 16)), Math::fast_ftoi(panf[1] * (1 << 16)) };

					switch (channels) {
						case 1: {

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

								in[0] = internal_buffer[i];
								in[1] = internal_buffer[i];
								DO_FILTER(0);
								DO_FILTER(1);
								p_buffer[(i << 1) + 0] = ((in[0] >> 16) * pan[0]);
								p_buffer[(i << 1) + 1] = ((in[1] >> 16) * pan[1]);
							}
						} break;
						case 2: {

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

								in[0] = internal_buffer[(i << 1) + 0];
								in[1] = internal_buffer[(i << 1) + 1];
								DO_FILTER(0);
								DO_FILTER(1);
								p_buffer[(i << 1) + 0] = ((in[0] >> 16) * pan[0]);
								p_buffer[(i << 1) + 1] = ((in[1] >> 16) * pan[1]);
							}
						} break;
						case 4: {

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

								in[0] = (internal_buffer[(i << 2) + 0] + internal_buffer[(i << 2) + 2]) >> 1;
								in[1] = (internal_buffer[(i << 2) + 1] + internal_buffer[(i << 2) + 3]) >> 1;
								DO_FILTER(0);
								DO_FILTER(1);
								p_buffer[(i << 1) + 0] = ((in[0] >> 16) * pan[0]);
								p_buffer[(i << 1) + 1] = ((in[1] >> 16) * pan[1]);
							}
						} break;
					}
					break;

				} break;
				case 4: {

					float xp = sd.panning.x * 0.5 + 0.5;
					float yp = sd.panning.y * 0.5 + 0.5;
					float panf[4] = { (1.0 - xp) * (1.0 - yp), (xp) * (1.0 - yp), (1.0 - xp) * (yp), (xp) * (yp) };
					panf[0] *= sd.volume;
					panf[1] *= sd.volume;
					panf[2] *= sd.volume;
					panf[3] *= sd.volume;

					int32_t pan[4] = {
						Math::fast_ftoi(panf[0] * (1 << 16)),
						Math::fast_ftoi(panf[1] * (1 << 16)),
						Math::fast_ftoi(panf[2] * (1 << 16)),
						Math::fast_ftoi(panf[3] * (1 << 16))
					};

					switch (channels) {
						case 1: {

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

								in[0] = internal_buffer[i];
								in[1] = internal_buffer[i];
								in[2] = internal_buffer[i];
								in[3] = internal_buffer[i];
								DO_FILTER(0);
								DO_FILTER(1);
								DO_FILTER(2);
								DO_FILTER(3);
								p_buffer[(i << 2) + 0] = ((in[0] >> 16) * pan[0]);
								p_buffer[(i << 2) + 1] = ((in[1] >> 16) * pan[1]);
								p_buffer[(i << 2) + 2] = ((in[2] >> 16) * pan[2]);
								p_buffer[(i << 2) + 3] = ((in[3] >> 16) * pan[3]);
							}
						} break;
						case 2: {

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

								in[0] = internal_buffer[(i << 1) + 0];
								in[1] = internal_buffer[(i << 1) + 1];
								in[2] = internal_buffer[(i << 1) + 0];
								in[3] = internal_buffer[(i << 1) + 1];
								DO_FILTER(0);
								DO_FILTER(1);
								DO_FILTER(2);
								DO_FILTER(3);
								p_buffer[(i << 2) + 0] = ((in[0] >> 16) * pan[0]);
								p_buffer[(i << 2) + 1] = ((in[1] >> 16) * pan[1]);
								p_buffer[(i << 2) + 2] = ((in[2] >> 16) * pan[2]);
								p_buffer[(i << 2) + 3] = ((in[3] >> 16) * pan[3]);
							}
						} break;
						case 4: {

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

								in[0] = internal_buffer[(i << 2) + 0];
								in[1] = internal_buffer[(i << 2) + 1];
								in[2] = internal_buffer[(i << 2) + 2];
								in[3] = internal_buffer[(i << 2) + 3];
								DO_FILTER(0);
								DO_FILTER(1);
								DO_FILTER(2);
								DO_FILTER(3);
								p_buffer[(i << 2) + 0] = ((in[0] >> 16) * pan[0]);
								p_buffer[(i << 2) + 1] = ((in[1] >> 16) * pan[1]);
								p_buffer[(i << 2) + 2] = ((in[2] >> 16) * pan[2]);
								p_buffer[(i << 2) + 3] = ((in[3] >> 16) * pan[3]);
							}
						} break;
					}
					break;

				} break;
				case 6: {

				} break;
			}
			p_buffer += to_mix * internal_buffer_channels;
			todo -= to_mix;
		}
	}

	return true;
}

void SpatialSoundServerSW::update(float p_delta) {

	List<ActiveVoice> to_disable;

	for (Set<ActiveVoice>::Element *E = active_voices.front(); E; E = E->next()) {

		Source *source = E->get().source;
		int voice = E->get().voice;

		if (voice != VOICE_IS_STREAM) {
			Source::Voice &v = source->voices[voice];
			ERR_CONTINUE(!v.active && !v.restart); // likely a bug...
		}

		//this could be optimized at some point... am not sure
		Space *space = space_owner.get(source->space);
		Room *room = room_owner.get(space->default_room);
		int max_level = -0x80000000;
		int rooms_culled = space->octree.cull_point(source->transform.origin, cull_rooms, MAX_CULL_ROOMS);
		for (int i = 0; i < rooms_culled; i++) {

			Room *r = cull_rooms[i];
			ERR_CONTINUE(r->bounds.is_empty()); // how did this happen??
			if (r->level <= max_level) //ignore optimization (level too low)
				continue;
			Vector3 local_point = r->inverse_transform.xform(source->transform.origin);
			if (!r->bounds.point_is_inside(local_point))
				continue;
			room = r;
			max_level = r->level;
		}

		//compute mixing weights (support for multiple listeners in the same output)
		float total_distance = 0;
		for (Set<RID>::Element *L = space->listeners.front(); L; L = L->next()) {
			Listener *listener = listener_owner.get(L->get());
			total_distance += listener->transform.origin.distance_to(source->transform.origin);
		}

		//compute spatialization variables, weighted according to distance
		float volume_attenuation = 0.0;
		float air_absorption_hf_cutoff = 0.0;
		float air_absorption = 0.0;
		float pitch_scale = 1.0;
		Vector3 panning;

		//print_line("listeners: "+itos(space->listeners.size()));

		for (Set<RID>::Element *L = space->listeners.front(); L; L = L->next()) {

			Listener *listener = listener_owner.get(L->get());

			Vector3 rel_vector = listener->transform.xform_inv(source->transform.origin);
			Vector3 source_rel_vector = source->transform.xform_inv(listener->transform.origin).normalized();
			float distance = rel_vector.length();
			float weight = distance / total_distance;
			float pscale = 1.0;

			float distance_scale = listener->params[LISTENER_PARAM_ATTENUATION_SCALE] * room->params[ROOM_PARAM_ATTENUATION_SCALE];
			float distance_min = source->params[SOURCE_PARAM_ATTENUATION_MIN_DISTANCE] * distance_scale;
			float distance_max = source->params[SOURCE_PARAM_ATTENUATION_MAX_DISTANCE] * distance_scale;
			float attenuation_exp = source->params[SOURCE_PARAM_ATTENUATION_DISTANCE_EXP];
			float attenuation = 1;

			//print_line("DIST MIN: "+rtos(distance_min));
			//print_line("DIST MAX: "+rtos(distance_max));
			if (distance_max > 0) {
				distance = CLAMP(distance, distance_min, distance_max);
				attenuation = Math::pow(1.0 - ((distance - distance_min) / (distance_max - distance_min)), CLAMP(attenuation_exp, 0.001, 16));
			}

			float hf_attenuation_cutoff = room->params[ROOM_PARAM_ATTENUATION_HF_CUTOFF];
			float hf_attenuation_exp = room->params[ROOM_PARAM_ATTENUATION_HF_RATIO_EXP];
			float hf_attenuation_floor = room->params[ROOM_PARAM_ATTENUATION_HF_FLOOR_DB];
			float absorption = Math::db2linear(Math::lerp(hf_attenuation_floor, 0, Math::pow(attenuation, hf_attenuation_exp)));

			// source emission cone

			float emission_deg = source->params[SOURCE_PARAM_EMISSION_CONE_DEGREES];
			float emission_attdb = source->params[SOURCE_PARAM_EMISSION_CONE_ATTENUATION_DB];
			absorption *= _get_attenuation(source_rel_vector.dot(Vector3(0, 0, -1)), emission_deg, emission_attdb);

			Vector3 vpanning = rel_vector.normalized();

			//listener stuff

			{

				// head cone

				float reception_deg = listener->params[LISTENER_PARAM_RECEPTION_CONE_DEGREES];
				float reception_attdb = listener->params[LISTENER_PARAM_RECEPTION_CONE_ATTENUATION_DB];

				absorption *= _get_attenuation(vpanning.dot(Vector3(0, 0, -1)), reception_deg, reception_attdb);

				// scale

				attenuation *= Math::db2linear(listener->params[LISTENER_PARAM_VOLUME_SCALE_DB]);
				pscale *= Math::db2linear(listener->params[LISTENER_PARAM_PITCH_SCALE]);
			}

			//add values

			volume_attenuation += weight * attenuation; // plus other stuff i guess
			air_absorption += weight * absorption;
			air_absorption_hf_cutoff += weight * hf_attenuation_cutoff;
			panning += vpanning * weight;
			//pitch_scale+=pscale*weight;
		}

		RoomReverb reverb_room;
		float reverb_send;

		/* APPLY ROOM SETTINGS */

		{
			pitch_scale *= room->params[ROOM_PARAM_PITCH_SCALE];
			volume_attenuation *= Math::db2linear(room->params[ROOM_PARAM_VOLUME_SCALE_DB]);
			reverb_room = room->reverb;
			reverb_send = Math::lerp(1.0, volume_attenuation, room->params[ROOM_PARAM_ATTENUATION_REVERB_SCALE]) * room->params[ROOM_PARAM_REVERB_SEND];
		}

		/* UPDATE VOICE & STREAM */

		if (voice == VOICE_IS_STREAM) {

			//update voice!!
			source->stream_data.panning = panning;
			source->stream_data.volume = volume_attenuation * Math::db2linear(source->params[SOURCE_PARAM_VOLUME_DB]);
			source->stream_data.reverb = reverb_room;
			source->stream_data.reverb_send = reverb_send;
			source->stream_data.filter_gain = air_absorption;
			source->stream_data.filter_cutoff = air_absorption_hf_cutoff;

			if (!source->stream) //stream is gone bye bye
				to_disable.push_back(ActiveVoice(source, voice)); // oh well..

		} else if (voice >= 0) {
			//update stream!!
			Source::Voice &v = source->voices[voice];

			if (v.restart)
				AudioServer::get_singleton()->voice_play(v.voice_rid, v.sample_rid);

			float volume_scale = Math::db2linear(v.volume_scale) * Math::db2linear(source->params[SOURCE_PARAM_VOLUME_DB]);
			float volume = volume_attenuation * volume_scale;
			reverb_send *= volume_scale;
			int mix_rate = v.sample_mix_rate * v.pitch_scale * pitch_scale * source->params[SOURCE_PARAM_PITCH_SCALE];

			if (mix_rate <= 0) {
				ERR_PRINT("Invalid mix rate for voice (0) check for invalid pitch_scale param.");
				to_disable.push_back(ActiveVoice(source, voice)); // oh well..
				continue; //invalid mix rate, disabling
			}
			if (v.restart || v.last_volume != volume)
				AudioServer::get_singleton()->voice_set_volume(v.voice_rid, volume);
			if (v.restart || v.last_mix_rate != mix_rate)
				AudioServer::get_singleton()->voice_set_mix_rate(v.voice_rid, mix_rate);
			if (v.restart || v.last_filter_gain != air_absorption || v.last_filter_cutoff != air_absorption_hf_cutoff)
				AudioServer::get_singleton()->voice_set_filter(v.voice_rid, AudioServer::FILTER_HIGH_SHELF, air_absorption_hf_cutoff, 1.0, air_absorption);
			if (v.restart || v.last_panning != panning)
				AudioServer::get_singleton()->voice_set_pan(v.voice_rid, panning.x, panning.y, panning.z);
			if (v.restart || v.last_reverb_room != reverb_room || v.last_reverb_send != reverb_send)
				AudioServer::get_singleton()->voice_set_reverb(v.voice_rid, AudioServer::ReverbRoomType(reverb_room), reverb_send);

			v.last_volume = volume;
			v.last_mix_rate = mix_rate;
			v.last_filter_gain = air_absorption;
			v.last_filter_cutoff = air_absorption_hf_cutoff;
			v.last_panning = panning;
			v.restart = false;
			v.active = true;

			if (!AudioServer::get_singleton()->voice_is_active(v.voice_rid))
				to_disable.push_back(ActiveVoice(source, voice)); // oh well..
		}
	}

	while (to_disable.size()) {

		ActiveVoice av = to_disable.front()->get();
		av.source->voices[av.voice].active = false;
		av.source->voices[av.voice].restart = false;
		active_voices.erase(av);
		to_disable.pop_front();
	}
}
void SpatialSoundServerSW::finish() {

	AudioServer::get_singleton()->free(internal_audio_stream_rid);
	memdelete(internal_audio_stream);

	_clean_up_owner(&source_owner, "Source");
	_clean_up_owner(&listener_owner, "Listener");
	_clean_up_owner(&room_owner, "Room");
	_clean_up_owner(&space_owner, "Space");

	memdelete_arr(internal_buffer);
}

SpatialSoundServerSW::SpatialSoundServerSW() {
}