/*************************************************************************/
/*  animation.cpp                                                        */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
/*                    http://www.godotengine.org                         */
/*************************************************************************/
/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur.                 */
/* Copyright (c) 2014-2017 Godot Engine contributors (cf. AUTHORS.md)    */
/*                                                                       */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the       */
/* "Software"), to deal in the Software without restriction, including   */
/* without limitation the rights to use, copy, modify, merge, publish,   */
/* distribute, sublicense, and/or sell copies of the Software, and to    */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions:                                             */
/*                                                                       */
/* The above copyright notice and this permission notice shall be        */
/* included in all copies or substantial portions of the Software.       */
/*                                                                       */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
/*************************************************************************/
#include "animation.h"
#include "geometry.h"

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

	String name = p_name;

	if (name == "length")
		set_length(p_value);
	else if (name == "loop")
		set_loop(p_value);
	else if (name == "step")
		set_step(p_value);
	else if (name.begins_with("tracks/")) {

		int track = name.get_slicec('/', 1).to_int();
		String what = name.get_slicec('/', 2);

		if (tracks.size() == track && what == "type") {

			String type = p_value;

			if (type == "transform") {

				add_track(TYPE_TRANSFORM);
			} else if (type == "value") {

				add_track(TYPE_VALUE);
			} else if (type == "method") {

				add_track(TYPE_METHOD);
			} else {

				return false;
			}

			return true;
		}

		ERR_FAIL_INDEX_V(track, tracks.size(), false);

		if (what == "path")
			track_set_path(track, p_value);
		else if (what == "interp")
			track_set_interpolation_type(track, InterpolationType(p_value.operator int()));
		else if (what == "loop_wrap")
			track_set_interpolation_loop_wrap(track, p_value);
		else if (what == "imported")
			track_set_imported(track, p_value);
		else if (what == "keys" || what == "key_values") {

			if (track_get_type(track) == TYPE_TRANSFORM) {

				TransformTrack *tt = static_cast<TransformTrack *>(tracks[track]);
				PoolVector<float> values = p_value;
				int vcount = values.size();

#if 0 // old compatibility hack
				if ((vcount%11) == 0) {


					PoolVector<float>::Read r = values.read();

					tt->transforms.resize(vcount/11);


					for(int i=0;i<(vcount/11);i++) {


						TKey<TransformKey> &tk=tt->transforms[i];
						const float *ofs=&r[i*11];
						tk.time=ofs[0];

						tk.value.loc.x=ofs[1];
						tk.value.loc.y=ofs[2];
						tk.value.loc.z=ofs[3];

						tk.value.rot.x=ofs[4];
						tk.value.rot.y=ofs[5];
						tk.value.rot.z=ofs[6];
						tk.value.rot.w=ofs[7];

						tk.value.scale.x=ofs[8];
						tk.value.scale.y=ofs[9];
						tk.value.scale.z=ofs[10];


					}
					return true;



				}
#endif
				ERR_FAIL_COND_V(vcount % 12, false); // shuld be multiple of 11

				PoolVector<float>::Read r = values.read();

				tt->transforms.resize(vcount / 12);

				for (int i = 0; i < (vcount / 12); i++) {

					TKey<TransformKey> &tk = tt->transforms[i];
					const float *ofs = &r[i * 12];
					tk.time = ofs[0];
					tk.transition = ofs[1];

					tk.value.loc.x = ofs[2];
					tk.value.loc.y = ofs[3];
					tk.value.loc.z = ofs[4];

					tk.value.rot.x = ofs[5];
					tk.value.rot.y = ofs[6];
					tk.value.rot.z = ofs[7];
					tk.value.rot.w = ofs[8];

					tk.value.scale.x = ofs[9];
					tk.value.scale.y = ofs[10];
					tk.value.scale.z = ofs[11];
				}

			} else if (track_get_type(track) == TYPE_VALUE) {

				ValueTrack *vt = static_cast<ValueTrack *>(tracks[track]);
				Dictionary d = p_value;
				ERR_FAIL_COND_V(!d.has("times"), false);
				ERR_FAIL_COND_V(!d.has("values"), false);
				if (d.has("cont")) {
					bool v = d["cont"];
					vt->update_mode = v ? UPDATE_CONTINUOUS : UPDATE_DISCRETE;
				}

				if (d.has("update")) {
					int um = d["update"];
					if (um < 0)
						um = 0;
					else if (um > 2)
						um = 2;
					vt->update_mode = UpdateMode(um);
				}

				PoolVector<float> times = d["times"];
				Array values = d["values"];

				ERR_FAIL_COND_V(times.size() != values.size(), false);

				if (times.size()) {

					int valcount = times.size();

					PoolVector<float>::Read rt = times.read();

					vt->values.resize(valcount);

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

						vt->values[i].time = rt[i];
						vt->values[i].value = values[i];
					}

					if (d.has("transitions")) {

						PoolVector<float> transitions = d["transitions"];
						ERR_FAIL_COND_V(transitions.size() != valcount, false);

						PoolVector<float>::Read rtr = transitions.read();

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

							vt->values[i].transition = rtr[i];
						}
					}
				}

				return true;

			} else {

				while (track_get_key_count(track))
					track_remove_key(track, 0); //well shouldn't be set anyway

				Dictionary d = p_value;
				ERR_FAIL_COND_V(!d.has("times"), false);
				ERR_FAIL_COND_V(!d.has("values"), false);

				PoolVector<float> times = d["times"];
				Array values = d["values"];

				ERR_FAIL_COND_V(times.size() != values.size(), false);

				if (times.size()) {

					int valcount = times.size();

					PoolVector<float>::Read rt = times.read();

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

						track_insert_key(track, rt[i], values[i]);
					}

					if (d.has("transitions")) {

						PoolVector<float> transitions = d["transitions"];
						ERR_FAIL_COND_V(transitions.size() != valcount, false);

						PoolVector<float>::Read rtr = transitions.read();

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

							track_set_key_transition(track, i, rtr[i]);
						}
					}
				}
			}
		} else
			return false;
	} else
		return false;

	return true;
}

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

	String name = p_name;

	if (name == "length")
		r_ret = length;
	else if (name == "loop")
		r_ret = loop;
	else if (name == "step")
		r_ret = step;
	else if (name.begins_with("tracks/")) {

		int track = name.get_slicec('/', 1).to_int();
		String what = name.get_slicec('/', 2);
		ERR_FAIL_INDEX_V(track, tracks.size(), false);
		if (what == "type") {

			switch (track_get_type(track)) {

				case TYPE_TRANSFORM: r_ret = "transform"; break;
				case TYPE_VALUE: r_ret = "value"; break;
				case TYPE_METHOD: r_ret = "method"; break;
			}

			return true;

		} else if (what == "path")
			r_ret = track_get_path(track);
		else if (what == "interp")
			r_ret = track_get_interpolation_type(track);
		else if (what == "loop_wrap")
			r_ret = track_get_interpolation_loop_wrap(track);
		else if (what == "imported")
			r_ret = track_is_imported(track);
		else if (what == "keys") {

			if (track_get_type(track) == TYPE_TRANSFORM) {

				PoolVector<real_t> keys;
				int kk = track_get_key_count(track);
				keys.resize(kk * 12);

				PoolVector<real_t>::Write w = keys.write();

				int idx = 0;
				for (int i = 0; i < track_get_key_count(track); i++) {

					Vector3 loc;
					Quat rot;
					Vector3 scale;
					transform_track_get_key(track, i, &loc, &rot, &scale);

					w[idx++] = track_get_key_time(track, i);
					w[idx++] = track_get_key_transition(track, i);
					w[idx++] = loc.x;
					w[idx++] = loc.y;
					w[idx++] = loc.z;

					w[idx++] = rot.x;
					w[idx++] = rot.y;
					w[idx++] = rot.z;
					w[idx++] = rot.w;

					w[idx++] = scale.x;
					w[idx++] = scale.y;
					w[idx++] = scale.z;
				}

				w = PoolVector<real_t>::Write();
				r_ret = keys;
				return true;

			} else if (track_get_type(track) == TYPE_VALUE) {

				const ValueTrack *vt = static_cast<const ValueTrack *>(tracks[track]);

				Dictionary d;

				PoolVector<float> key_times;
				PoolVector<float> key_transitions;
				Array key_values;

				int kk = vt->values.size();

				key_times.resize(kk);
				key_transitions.resize(kk);
				key_values.resize(kk);

				PoolVector<float>::Write wti = key_times.write();
				PoolVector<float>::Write wtr = key_transitions.write();

				int idx = 0;

				const TKey<Variant> *vls = vt->values.ptr();

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

					wti[idx] = vls[i].time;
					wtr[idx] = vls[i].transition;
					key_values[idx] = vls[i].value;
					idx++;
				}

				wti = PoolVector<float>::Write();
				wtr = PoolVector<float>::Write();

				d["times"] = key_times;
				d["transitions"] = key_transitions;
				d["values"] = key_values;
				if (track_get_type(track) == TYPE_VALUE) {
					d["update"] = value_track_get_update_mode(track);
				}

				r_ret = d;

				return true;

			} else {

				Dictionary d;

				PoolVector<float> key_times;
				PoolVector<float> key_transitions;
				Array key_values;

				int kk = track_get_key_count(track);

				key_times.resize(kk);
				key_transitions.resize(kk);
				key_values.resize(kk);

				PoolVector<float>::Write wti = key_times.write();
				PoolVector<float>::Write wtr = key_transitions.write();

				int idx = 0;
				for (int i = 0; i < track_get_key_count(track); i++) {

					wti[idx] = track_get_key_time(track, i);
					wtr[idx] = track_get_key_transition(track, i);
					key_values[idx] = track_get_key_value(track, i);
					idx++;
				}

				wti = PoolVector<float>::Write();
				wtr = PoolVector<float>::Write();

				d["times"] = key_times;
				d["transitions"] = key_transitions;
				d["values"] = key_values;
				if (track_get_type(track) == TYPE_VALUE) {
					d["update"] = value_track_get_update_mode(track);
				}

				r_ret = d;

				return true;
			}
		} else
			return false;
	} else
		return false;

	return true;
}

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

	p_list->push_back(PropertyInfo(Variant::REAL, "length", PROPERTY_HINT_RANGE, "0.001,99999,0.001"));
	p_list->push_back(PropertyInfo(Variant::BOOL, "loop"));
	p_list->push_back(PropertyInfo(Variant::REAL, "step", PROPERTY_HINT_RANGE, "0,4096,0.001"));

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

		p_list->push_back(PropertyInfo(Variant::STRING, "tracks/" + itos(i) + "/type", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_NOEDITOR));
		p_list->push_back(PropertyInfo(Variant::NODE_PATH, "tracks/" + itos(i) + "/path", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_NOEDITOR));
		p_list->push_back(PropertyInfo(Variant::INT, "tracks/" + itos(i) + "/interp", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_NOEDITOR));
		p_list->push_back(PropertyInfo(Variant::BOOL, "tracks/" + itos(i) + "/loop_wrap", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_NOEDITOR));
		p_list->push_back(PropertyInfo(Variant::BOOL, "tracks/" + itos(i) + "/imported", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_NOEDITOR));
		p_list->push_back(PropertyInfo(Variant::ARRAY, "tracks/" + itos(i) + "/keys", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_NOEDITOR));
	}
}

int Animation::add_track(TrackType p_type, int p_at_pos) {

	if (p_at_pos < 0 || p_at_pos >= tracks.size())
		p_at_pos = tracks.size();

	switch (p_type) {

		case TYPE_TRANSFORM: {

			TransformTrack *tt = memnew(TransformTrack);
			tracks.insert(p_at_pos, tt);
		} break;
		case TYPE_VALUE: {

			tracks.insert(p_at_pos, memnew(ValueTrack));

		} break;
		case TYPE_METHOD: {

			tracks.insert(p_at_pos, memnew(MethodTrack));

		} break;
		default: {

			ERR_PRINT("Unknown track type");
		}
	}
	emit_changed();
	return p_at_pos;
}

void Animation::remove_track(int p_track) {

	ERR_FAIL_INDEX(p_track, tracks.size());
	Track *t = tracks[p_track];

	switch (t->type) {

		case TYPE_TRANSFORM: {

			TransformTrack *tt = static_cast<TransformTrack *>(t);
			_clear(tt->transforms);

		} break;
		case TYPE_VALUE: {

			ValueTrack *vt = static_cast<ValueTrack *>(t);
			_clear(vt->values);

		} break;
		case TYPE_METHOD: {

			MethodTrack *mt = static_cast<MethodTrack *>(t);
			_clear(mt->methods);

		} break;
	}

	memdelete(t);
	tracks.remove(p_track);
	emit_changed();
}

int Animation::get_track_count() const {

	return tracks.size();
}

Animation::TrackType Animation::track_get_type(int p_track) const {

	ERR_FAIL_INDEX_V(p_track, tracks.size(), TYPE_TRANSFORM);
	return tracks[p_track]->type;
}

void Animation::track_set_path(int p_track, const NodePath &p_path) {

	ERR_FAIL_INDEX(p_track, tracks.size());
	tracks[p_track]->path = p_path;
	emit_changed();
}

NodePath Animation::track_get_path(int p_track) const {

	ERR_FAIL_INDEX_V(p_track, tracks.size(), NodePath());
	return tracks[p_track]->path;
}

int Animation::find_track(const NodePath &p_path) const {

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

		if (tracks[i]->path == p_path)
			return i;
	};
	return -1;
};

void Animation::track_set_interpolation_type(int p_track, InterpolationType p_interp) {

	ERR_FAIL_INDEX(p_track, tracks.size());
	ERR_FAIL_INDEX(p_interp, 3);
	tracks[p_track]->interpolation = p_interp;
	emit_changed();
}

Animation::InterpolationType Animation::track_get_interpolation_type(int p_track) const {

	ERR_FAIL_INDEX_V(p_track, tracks.size(), INTERPOLATION_NEAREST);
	return tracks[p_track]->interpolation;
}

void Animation::track_set_interpolation_loop_wrap(int p_track, bool p_enable) {
	ERR_FAIL_INDEX(p_track, tracks.size());
	tracks[p_track]->loop_wrap = p_enable;
	emit_changed();
}

bool Animation::track_get_interpolation_loop_wrap(int p_track) const {

	ERR_FAIL_INDEX_V(p_track, tracks.size(), INTERPOLATION_NEAREST);
	return tracks[p_track]->loop_wrap;
}

// transform
/*
template<class T>
int Animation::_insert_pos(float p_time, T& p_keys) {

	// simple, linear time inset that should be fast enough in reality.

	int idx=p_keys.size();

	while(true) {


		if (idx==0 || p_keys[idx-1].time < p_time) {
			//condition for insertion.
			p_keys.insert(idx,T());
			return idx;
		} else if (p_keys[idx-1].time == p_time) {

			// condition for replacing.
			return idx-1;
		}

		idx--;
	}

}
*/
template <class T, class V>
int Animation::_insert(float p_time, T &p_keys, const V &p_value) {

	int idx = p_keys.size();

	while (true) {

		if (idx == 0 || p_keys[idx - 1].time < p_time) {
			//condition for insertion.
			p_keys.insert(idx, p_value);
			return idx;
		} else if (p_keys[idx - 1].time == p_time) {

			// condition for replacing.
			p_keys[idx - 1] = p_value;
			return idx - 1;
		}

		idx--;
	}

	return -1;
}

template <class T>
void Animation::_clear(T &p_keys) {

	p_keys.clear();
}

Error Animation::transform_track_get_key(int p_track, int p_key, Vector3 *r_loc, Quat *r_rot, Vector3 *r_scale) const {

	ERR_FAIL_INDEX_V(p_track, tracks.size(), ERR_INVALID_PARAMETER);
	Track *t = tracks[p_track];

	TransformTrack *tt = static_cast<TransformTrack *>(t);
	ERR_FAIL_COND_V(t->type != TYPE_TRANSFORM, ERR_INVALID_PARAMETER);
	ERR_FAIL_INDEX_V(p_key, tt->transforms.size(), ERR_INVALID_PARAMETER);

	if (r_loc)
		*r_loc = tt->transforms[p_key].value.loc;
	if (r_rot)
		*r_rot = tt->transforms[p_key].value.rot;
	if (r_scale)
		*r_scale = tt->transforms[p_key].value.scale;

	return OK;
}

int Animation::transform_track_insert_key(int p_track, float p_time, const Vector3 p_loc, const Quat &p_rot, const Vector3 &p_scale) {

	ERR_FAIL_INDEX_V(p_track, tracks.size(), -1);
	Track *t = tracks[p_track];
	ERR_FAIL_COND_V(t->type != TYPE_TRANSFORM, -1);

	TransformTrack *tt = static_cast<TransformTrack *>(t);

	TKey<TransformKey> tkey;
	tkey.time = p_time;
	tkey.value.loc = p_loc;
	tkey.value.rot = p_rot;
	tkey.value.scale = p_scale;

	int ret = _insert(p_time, tt->transforms, tkey);
	emit_changed();
	return ret;
}

void Animation::track_remove_key_at_pos(int p_track, float p_pos) {

	int idx = track_find_key(p_track, p_pos, true);
	ERR_FAIL_COND(idx < 0);
	track_remove_key(p_track, idx);
}

void Animation::track_remove_key(int p_track, int p_idx) {

	ERR_FAIL_INDEX(p_track, tracks.size());
	Track *t = tracks[p_track];

	switch (t->type) {
		case TYPE_TRANSFORM: {

			TransformTrack *tt = static_cast<TransformTrack *>(t);
			ERR_FAIL_INDEX(p_idx, tt->transforms.size());
			tt->transforms.remove(p_idx);

		} break;
		case TYPE_VALUE: {

			ValueTrack *vt = static_cast<ValueTrack *>(t);
			ERR_FAIL_INDEX(p_idx, vt->values.size());
			vt->values.remove(p_idx);

		} break;
		case TYPE_METHOD: {

			MethodTrack *mt = static_cast<MethodTrack *>(t);
			ERR_FAIL_INDEX(p_idx, mt->methods.size());
			mt->methods.remove(p_idx);

		} break;
	}

	emit_changed();
}

int Animation::track_find_key(int p_track, float p_time, bool p_exact) const {

	ERR_FAIL_INDEX_V(p_track, tracks.size(), -1);
	Track *t = tracks[p_track];

	switch (t->type) {
		case TYPE_TRANSFORM: {

			TransformTrack *tt = static_cast<TransformTrack *>(t);
			int k = _find(tt->transforms, p_time);
			if (k < 0 || k >= tt->transforms.size())
				return -1;
			if (tt->transforms[k].time != p_time && p_exact)
				return -1;
			return k;

		} break;
		case TYPE_VALUE: {

			ValueTrack *vt = static_cast<ValueTrack *>(t);
			int k = _find(vt->values, p_time);
			if (k < 0 || k >= vt->values.size())
				return -1;
			if (vt->values[k].time != p_time && p_exact)
				return -1;
			return k;

		} break;
		case TYPE_METHOD: {

			MethodTrack *mt = static_cast<MethodTrack *>(t);
			int k = _find(mt->methods, p_time);
			if (k < 0 || k >= mt->methods.size())
				return -1;
			if (mt->methods[k].time != p_time && p_exact)
				return -1;
			return k;

		} break;
	}

	return -1;
}

void Animation::track_insert_key(int p_track, float p_time, const Variant &p_value, float p_transition) {

	ERR_FAIL_INDEX(p_track, tracks.size());
	Track *t = tracks[p_track];

	switch (t->type) {

		case TYPE_TRANSFORM: {

			Dictionary d = p_value;
			Vector3 loc;
			if (d.has("loc"))
				loc = d["loc"];

			Quat rot;
			if (d.has("rot"))
				rot = d["rot"];

			Vector3 scale;
			if (d.has("scale"))
				scale = d["scale"];

			int idx = transform_track_insert_key(p_track, p_time, loc, rot, scale);
			track_set_key_transition(p_track, idx, p_transition);

		} break;
		case TYPE_VALUE: {

			ValueTrack *vt = static_cast<ValueTrack *>(t);

			TKey<Variant> k;
			k.time = p_time;
			k.transition = p_transition;
			k.value = p_value;
			_insert(p_time, vt->values, k);

		} break;
		case TYPE_METHOD: {

			MethodTrack *mt = static_cast<MethodTrack *>(t);

			ERR_FAIL_COND(p_value.get_type() != Variant::DICTIONARY);

			Dictionary d = p_value;
			ERR_FAIL_COND(!d.has("method") || d["method"].get_type() != Variant::STRING);
			ERR_FAIL_COND(!d.has("args") || !d["args"].is_array());

			MethodKey k;

			k.time = p_time;
			k.transition = p_transition;
			k.method = d["method"];
			k.params = d["args"];

			_insert(p_time, mt->methods, k);

		} break;
	}

	emit_changed();
}

int Animation::track_get_key_count(int p_track) const {

	ERR_FAIL_INDEX_V(p_track, tracks.size(), -1);
	Track *t = tracks[p_track];

	switch (t->type) {

		case TYPE_TRANSFORM: {

			TransformTrack *tt = static_cast<TransformTrack *>(t);
			return tt->transforms.size();
		} break;
		case TYPE_VALUE: {

			ValueTrack *vt = static_cast<ValueTrack *>(t);
			return vt->values.size();

		} break;
		case TYPE_METHOD: {

			MethodTrack *mt = static_cast<MethodTrack *>(t);
			return mt->methods.size();
		} break;
	}

	ERR_FAIL_V(-1);
}

Variant Animation::track_get_key_value(int p_track, int p_key_idx) const {

	ERR_FAIL_INDEX_V(p_track, tracks.size(), Variant());
	Track *t = tracks[p_track];

	switch (t->type) {

		case TYPE_TRANSFORM: {

			TransformTrack *tt = static_cast<TransformTrack *>(t);
			ERR_FAIL_INDEX_V(p_key_idx, tt->transforms.size(), Variant());

			Dictionary d;
			d["loc"] = tt->transforms[p_key_idx].value.loc;
			d["rot"] = tt->transforms[p_key_idx].value.rot;
			d["scale"] = tt->transforms[p_key_idx].value.scale;

			return d;
		} break;
		case TYPE_VALUE: {

			ValueTrack *vt = static_cast<ValueTrack *>(t);
			ERR_FAIL_INDEX_V(p_key_idx, vt->values.size(), Variant());
			return vt->values[p_key_idx].value;

		} break;
		case TYPE_METHOD: {

			MethodTrack *mt = static_cast<MethodTrack *>(t);
			ERR_FAIL_INDEX_V(p_key_idx, mt->methods.size(), Variant());
			Dictionary d;
			d["method"] = mt->methods[p_key_idx].method;
			d["args"] = mt->methods[p_key_idx].params;
			return d;

		} break;
	}

	ERR_FAIL_V(Variant());
}

float Animation::track_get_key_time(int p_track, int p_key_idx) const {

	ERR_FAIL_INDEX_V(p_track, tracks.size(), -1);
	Track *t = tracks[p_track];

	switch (t->type) {

		case TYPE_TRANSFORM: {

			TransformTrack *tt = static_cast<TransformTrack *>(t);
			ERR_FAIL_INDEX_V(p_key_idx, tt->transforms.size(), -1);
			return tt->transforms[p_key_idx].time;
		} break;
		case TYPE_VALUE: {

			ValueTrack *vt = static_cast<ValueTrack *>(t);
			ERR_FAIL_INDEX_V(p_key_idx, vt->values.size(), -1);
			return vt->values[p_key_idx].time;

		} break;
		case TYPE_METHOD: {

			MethodTrack *mt = static_cast<MethodTrack *>(t);
			ERR_FAIL_INDEX_V(p_key_idx, mt->methods.size(), -1);
			return mt->methods[p_key_idx].time;

		} break;
	}

	ERR_FAIL_V(-1);
}

float Animation::track_get_key_transition(int p_track, int p_key_idx) const {

	ERR_FAIL_INDEX_V(p_track, tracks.size(), -1);
	Track *t = tracks[p_track];

	switch (t->type) {

		case TYPE_TRANSFORM: {

			TransformTrack *tt = static_cast<TransformTrack *>(t);
			ERR_FAIL_INDEX_V(p_key_idx, tt->transforms.size(), -1);
			return tt->transforms[p_key_idx].transition;
		} break;
		case TYPE_VALUE: {

			ValueTrack *vt = static_cast<ValueTrack *>(t);
			ERR_FAIL_INDEX_V(p_key_idx, vt->values.size(), -1);
			return vt->values[p_key_idx].transition;

		} break;
		case TYPE_METHOD: {

			MethodTrack *mt = static_cast<MethodTrack *>(t);
			ERR_FAIL_INDEX_V(p_key_idx, mt->methods.size(), -1);
			return mt->methods[p_key_idx].transition;

		} break;
	}

	ERR_FAIL_V(0);
}

void Animation::track_set_key_value(int p_track, int p_key_idx, const Variant &p_value) {

	ERR_FAIL_INDEX(p_track, tracks.size());
	Track *t = tracks[p_track];

	switch (t->type) {

		case TYPE_TRANSFORM: {

			TransformTrack *tt = static_cast<TransformTrack *>(t);
			ERR_FAIL_INDEX(p_key_idx, tt->transforms.size());
			Dictionary d = p_value;
			if (d.has("loc"))
				tt->transforms[p_key_idx].value.loc = d["loc"];
			if (d.has("rot"))
				tt->transforms[p_key_idx].value.rot = d["rot"];
			if (d.has("scale"))
				tt->transforms[p_key_idx].value.scale = d["scale"];

		} break;
		case TYPE_VALUE: {

			ValueTrack *vt = static_cast<ValueTrack *>(t);
			ERR_FAIL_INDEX(p_key_idx, vt->values.size());
			vt->values[p_key_idx].value = p_value;

		} break;
		case TYPE_METHOD: {

			MethodTrack *mt = static_cast<MethodTrack *>(t);
			ERR_FAIL_INDEX(p_key_idx, mt->methods.size());
			Dictionary d = p_value;
			if (d.has("method"))
				mt->methods[p_key_idx].method = d["method"];
			if (d.has("args"))
				mt->methods[p_key_idx].params = d["args"];
		} break;
	}
}

void Animation::track_set_key_transition(int p_track, int p_key_idx, float p_transition) {

	ERR_FAIL_INDEX(p_track, tracks.size());
	Track *t = tracks[p_track];

	switch (t->type) {

		case TYPE_TRANSFORM: {

			TransformTrack *tt = static_cast<TransformTrack *>(t);
			ERR_FAIL_INDEX(p_key_idx, tt->transforms.size());
			tt->transforms[p_key_idx].transition = p_transition;
		} break;
		case TYPE_VALUE: {

			ValueTrack *vt = static_cast<ValueTrack *>(t);
			ERR_FAIL_INDEX(p_key_idx, vt->values.size());
			vt->values[p_key_idx].transition = p_transition;

		} break;
		case TYPE_METHOD: {

			MethodTrack *mt = static_cast<MethodTrack *>(t);
			ERR_FAIL_INDEX(p_key_idx, mt->methods.size());
			mt->methods[p_key_idx].transition = p_transition;

		} break;
	}
}

template <class K>
int Animation::_find(const Vector<K> &p_keys, float p_time) const {

	int len = p_keys.size();
	if (len == 0)
		return -2;

	int low = 0;
	int high = len - 1;
	int middle;

	const K *keys = &p_keys[0];

	while (low <= high) {

		middle = (low + high) / 2;

		if (p_time == keys[middle].time) { //match
			return middle;
		} else if (p_time < keys[middle].time)
			high = middle - 1; //search low end of array
		else
			low = middle + 1; //search high end of array
	}

	if (keys[middle].time > p_time)
		middle--;

	return middle;
}

Animation::TransformKey Animation::_interpolate(const Animation::TransformKey &p_a, const Animation::TransformKey &p_b, float p_c) const {

	TransformKey ret;
	ret.loc = _interpolate(p_a.loc, p_b.loc, p_c);
	ret.rot = _interpolate(p_a.rot, p_b.rot, p_c);
	ret.scale = _interpolate(p_a.scale, p_b.scale, p_c);

	return ret;
}

Vector3 Animation::_interpolate(const Vector3 &p_a, const Vector3 &p_b, float p_c) const {

	return p_a.linear_interpolate(p_b, p_c);
}
Quat Animation::_interpolate(const Quat &p_a, const Quat &p_b, float p_c) const {

	return p_a.slerp(p_b, p_c);
}
Variant Animation::_interpolate(const Variant &p_a, const Variant &p_b, float p_c) const {

	Variant dst;
	Variant::interpolate(p_a, p_b, p_c, dst);
	return dst;
}

float Animation::_interpolate(const float &p_a, const float &p_b, float p_c) const {

	return p_a * (1.0 - p_c) + p_b * p_c;
}

Animation::TransformKey Animation::_cubic_interpolate(const Animation::TransformKey &p_pre_a, const Animation::TransformKey &p_a, const Animation::TransformKey &p_b, const Animation::TransformKey &p_post_b, float p_c) const {

	Animation::TransformKey tk;

	tk.loc = p_a.loc.cubic_interpolate(p_b.loc, p_pre_a.loc, p_post_b.loc, p_c);
	tk.scale = p_a.scale.cubic_interpolate(p_b.scale, p_pre_a.scale, p_post_b.scale, p_c);
	tk.rot = p_a.rot.cubic_slerp(p_b.rot, p_pre_a.rot, p_post_b.rot, p_c);

	return tk;
}
Vector3 Animation::_cubic_interpolate(const Vector3 &p_pre_a, const Vector3 &p_a, const Vector3 &p_b, const Vector3 &p_post_b, float p_c) const {

	return p_a.cubic_interpolate(p_b, p_pre_a, p_post_b, p_c);
}
Quat Animation::_cubic_interpolate(const Quat &p_pre_a, const Quat &p_a, const Quat &p_b, const Quat &p_post_b, float p_c) const {

	return p_a.cubic_slerp(p_b, p_pre_a, p_post_b, p_c);
}
Variant Animation::_cubic_interpolate(const Variant &p_pre_a, const Variant &p_a, const Variant &p_b, const Variant &p_post_b, float p_c) const {

	Variant::Type type_a = p_a.get_type();
	Variant::Type type_b = p_b.get_type();
	Variant::Type type_pa = p_pre_a.get_type();
	Variant::Type type_pb = p_post_b.get_type();

	//make int and real play along

	uint32_t vformat = 1 << type_a;
	vformat |= 1 << type_b;
	vformat |= 1 << type_pa;
	vformat |= 1 << type_pb;

	if (vformat == ((1 << Variant::INT) | (1 << Variant::REAL)) || vformat == (1 << Variant::REAL)) {
		//mix of real and int

		real_t p0 = p_pre_a;
		real_t p1 = p_a;
		real_t p2 = p_b;
		real_t p3 = p_post_b;

		float t = p_c;
		float t2 = t * t;
		float t3 = t2 * t;

		return 0.5f * ((p1 * 2.0f) +
							  (-p0 + p2) * t +
							  (2.0f * p0 - 5.0f * p1 + 4 * p2 - p3) * t2 +
							  (-p0 + 3.0f * p1 - 3.0f * p2 + p3) * t3);

	} else if ((vformat & (vformat - 1))) {

		return p_a; //can't interpolate, mix of types
	}

	switch (type_a) {

		case Variant::VECTOR2: {

			Vector2 a = p_a;
			Vector2 b = p_b;
			Vector2 pa = p_pre_a;
			Vector2 pb = p_post_b;

			return a.cubic_interpolate(b, pa, pb, p_c);

		} break;
		case Variant::RECT2: {

			Rect2 a = p_a;
			Rect2 b = p_b;
			Rect2 pa = p_pre_a;
			Rect2 pb = p_post_b;

			return Rect2(
					a.position.cubic_interpolate(b.position, pa.position, pb.position, p_c),
					a.size.cubic_interpolate(b.size, pa.size, pb.size, p_c));

		} break;
		case Variant::VECTOR3: {

			Vector3 a = p_a;
			Vector3 b = p_b;
			Vector3 pa = p_pre_a;
			Vector3 pb = p_post_b;

			return a.cubic_interpolate(b, pa, pb, p_c);

		} break;
		case Variant::QUAT: {

			Quat a = p_a;
			Quat b = p_b;
			Quat pa = p_pre_a;
			Quat pb = p_post_b;

			return a.cubic_slerp(b, pa, pb, p_c);

		} break;
		case Variant::RECT3: {

			Rect3 a = p_a;
			Rect3 b = p_b;
			Rect3 pa = p_pre_a;
			Rect3 pb = p_post_b;

			return Rect3(
					a.pos.cubic_interpolate(b.pos, pa.pos, pb.pos, p_c),
					a.size.cubic_interpolate(b.size, pa.size, pb.size, p_c));
		} break;
		default: {

			return _interpolate(p_a, p_b, p_c);
		}
	}

	return Variant();
}
float Animation::_cubic_interpolate(const float &p_pre_a, const float &p_a, const float &p_b, const float &p_post_b, float p_c) const {

	return _interpolate(p_a, p_b, p_c);
}

template <class T>
T Animation::_interpolate(const Vector<TKey<T> > &p_keys, float p_time, InterpolationType p_interp, bool p_loop_wrap, bool *p_ok) const {

	int len = _find(p_keys, length) + 1; // try to find last key (there may be more past the end)

	if (len <= 0) {
		// (-1 or -2 returned originally) (plus one above)
		// meaning no keys, or only key time is larger than length
		if (p_ok)
			*p_ok = false;
		return T();
	} else if (len == 1) { // one key found (0+1), return it

		if (p_ok)
			*p_ok = true;
		return p_keys[0].value;
	}

	int idx = _find(p_keys, p_time);

	ERR_FAIL_COND_V(idx == -2, T());

	if (p_ok)
		*p_ok = true;

	int next = 0;
	float c = 0;
	// prepare for all cases of interpolation

	if (loop && p_loop_wrap) {
		// loop
		if (idx >= 0) {

			if ((idx + 1) < len) {

				next = idx + 1;
				float delta = p_keys[next].time - p_keys[idx].time;
				float from = p_time - p_keys[idx].time;

				if (Math::absf(delta) > CMP_EPSILON)
					c = from / delta;
				else
					c = 0;

			} else {

				next = 0;
				float delta = (length - p_keys[idx].time) + p_keys[next].time;
				float from = p_time - p_keys[idx].time;

				if (Math::absf(delta) > CMP_EPSILON)
					c = from / delta;
				else
					c = 0;
			}

		} else {
			// on loop, behind first key
			idx = len - 1;
			next = 0;
			float endtime = (length - p_keys[idx].time);
			if (endtime < 0) // may be keys past the end
				endtime = 0;
			float delta = endtime + p_keys[next].time;
			float from = endtime + p_time;

			if (Math::absf(delta) > CMP_EPSILON)
				c = from / delta;
			else
				c = 0;
		}

	} else { // no loop

		if (idx >= 0) {

			if ((idx + 1) < len) {

				next = idx + 1;
				float delta = p_keys[next].time - p_keys[idx].time;
				float from = p_time - p_keys[idx].time;

				if (Math::absf(delta) > CMP_EPSILON)
					c = from / delta;
				else
					c = 0;

			} else {

				next = idx;
			}

		} else if (idx < 0) {

			idx = next = 0;
		}
	}

	float tr = p_keys[idx].transition;

	if (tr == 0 || idx == next) {
		// don't interpolate if not needed
		return p_keys[idx].value;
	}

	if (tr != 1.0) {

		c = Math::ease(c, tr);
	}

	switch (p_interp) {

		case INTERPOLATION_NEAREST: {

			return p_keys[idx].value;
		} break;
		case INTERPOLATION_LINEAR: {

			return _interpolate(p_keys[idx].value, p_keys[next].value, c);
		} break;
		case INTERPOLATION_CUBIC: {
			int pre = idx - 1;
			if (pre < 0)
				pre = 0;
			int post = next + 1;
			if (post >= len)
				post = next;

			return _cubic_interpolate(p_keys[pre].value, p_keys[idx].value, p_keys[next].value, p_keys[post].value, c);

		} break;
		default: return p_keys[idx].value;
	}

	// do a barrel roll
}

Error Animation::transform_track_interpolate(int p_track, float p_time, Vector3 *r_loc, Quat *r_rot, Vector3 *r_scale) const {

	ERR_FAIL_INDEX_V(p_track, tracks.size(), ERR_INVALID_PARAMETER);
	Track *t = tracks[p_track];
	ERR_FAIL_COND_V(t->type != TYPE_TRANSFORM, ERR_INVALID_PARAMETER);

	TransformTrack *tt = static_cast<TransformTrack *>(t);

	bool ok;

	TransformKey tk = _interpolate(tt->transforms, p_time, tt->interpolation, tt->loop_wrap, &ok);

	if (!ok) // ??
		return ERR_UNAVAILABLE;

	if (r_loc)
		*r_loc = tk.loc;

	if (r_rot)
		*r_rot = tk.rot;

	if (r_scale)
		*r_scale = tk.scale;

	return OK;
}

Variant Animation::value_track_interpolate(int p_track, float p_time) const {

	ERR_FAIL_INDEX_V(p_track, tracks.size(), 0);
	Track *t = tracks[p_track];
	ERR_FAIL_COND_V(t->type != TYPE_VALUE, Variant());
	ValueTrack *vt = static_cast<ValueTrack *>(t);

	bool ok;

	Variant res = _interpolate(vt->values, p_time, vt->update_mode == UPDATE_CONTINUOUS ? vt->interpolation : INTERPOLATION_NEAREST, vt->loop_wrap, &ok);

	if (ok) {

		return res;
	}

	return Variant();
}

void Animation::_value_track_get_key_indices_in_range(const ValueTrack *vt, float from_time, float to_time, List<int> *p_indices) const {

	if (from_time != length && to_time == length)
		to_time = length * 1.01; //include a little more if at the end
	int to = _find(vt->values, to_time);

	// can't really send the events == time, will be sent in the next frame.
	// if event>=len then it will probably never be requested by the anim player.

	if (to >= 0 && vt->values[to].time >= to_time)
		to--;

	if (to < 0)
		return; // not bother

	int from = _find(vt->values, from_time);

	// position in the right first event.+
	if (from < 0 || vt->values[from].time < from_time)
		from++;

	int max = vt->values.size();

	for (int i = from; i <= to; i++) {

		ERR_CONTINUE(i < 0 || i >= max); // shouldn't happen
		p_indices->push_back(i);
	}
}

void Animation::value_track_get_key_indices(int p_track, float p_time, float p_delta, List<int> *p_indices) const {

	ERR_FAIL_INDEX(p_track, tracks.size());
	Track *t = tracks[p_track];
	ERR_FAIL_COND(t->type != TYPE_VALUE);

	ValueTrack *vt = static_cast<ValueTrack *>(t);

	float from_time = p_time - p_delta;
	float to_time = p_time;

	if (from_time > to_time)
		SWAP(from_time, to_time);

	if (loop) {

		from_time = Math::fposmod(from_time, length);
		to_time = Math::fposmod(to_time, length);

		if (from_time > to_time) {
			// handle loop by splitting
			_value_track_get_key_indices_in_range(vt, length - from_time, length, p_indices);
			_value_track_get_key_indices_in_range(vt, 0, to_time, p_indices);
			return;
		}
	} else {

		if (from_time < 0)
			from_time = 0;
		if (from_time > length)
			from_time = length;

		if (to_time < 0)
			to_time = 0;
		if (to_time > length)
			to_time = length;
	}

	_value_track_get_key_indices_in_range(vt, from_time, to_time, p_indices);
}

void Animation::value_track_set_update_mode(int p_track, UpdateMode p_mode) {

	ERR_FAIL_INDEX(p_track, tracks.size());
	Track *t = tracks[p_track];
	ERR_FAIL_COND(t->type != TYPE_VALUE);
	ERR_FAIL_INDEX(p_mode, 3);

	ValueTrack *vt = static_cast<ValueTrack *>(t);
	vt->update_mode = p_mode;
}

Animation::UpdateMode Animation::value_track_get_update_mode(int p_track) const {

	ERR_FAIL_INDEX_V(p_track, tracks.size(), UPDATE_CONTINUOUS);
	Track *t = tracks[p_track];
	ERR_FAIL_COND_V(t->type != TYPE_VALUE, UPDATE_CONTINUOUS);

	ValueTrack *vt = static_cast<ValueTrack *>(t);
	return vt->update_mode;
}

void Animation::_method_track_get_key_indices_in_range(const MethodTrack *mt, float from_time, float to_time, List<int> *p_indices) const {

	if (from_time != length && to_time == length)
		to_time = length * 1.01; //include a little more if at the end

	int to = _find(mt->methods, to_time);

	// can't really send the events == time, will be sent in the next frame.
	// if event>=len then it will probably never be requested by the anim player.

	if (to >= 0 && mt->methods[to].time >= to_time)
		to--;

	if (to < 0)
		return; // not bother

	int from = _find(mt->methods, from_time);

	// position in the right first event.+
	if (from < 0 || mt->methods[from].time < from_time)
		from++;

	int max = mt->methods.size();

	for (int i = from; i <= to; i++) {

		ERR_CONTINUE(i < 0 || i >= max); // shouldn't happen
		p_indices->push_back(i);
	}
}

void Animation::method_track_get_key_indices(int p_track, float p_time, float p_delta, List<int> *p_indices) const {

	ERR_FAIL_INDEX(p_track, tracks.size());
	Track *t = tracks[p_track];
	ERR_FAIL_COND(t->type != TYPE_METHOD);

	MethodTrack *mt = static_cast<MethodTrack *>(t);

	float from_time = p_time - p_delta;
	float to_time = p_time;

	if (from_time > to_time)
		SWAP(from_time, to_time);

	if (loop) {

		if (from_time > length || from_time < 0)
			from_time = Math::fposmod(from_time, length);

		if (to_time > length || to_time < 0)
			to_time = Math::fposmod(to_time, length);

		if (from_time > to_time) {
			// handle loop by splitting
			_method_track_get_key_indices_in_range(mt, from_time, length, p_indices);
			_method_track_get_key_indices_in_range(mt, 0, to_time, p_indices);
			return;
		}
	} else {

		if (from_time < 0)
			from_time = 0;
		if (from_time > length)
			from_time = length;

		if (to_time < 0)
			to_time = 0;
		if (to_time > length)
			to_time = length;
	}

	_method_track_get_key_indices_in_range(mt, from_time, to_time, p_indices);
}
Vector<Variant> Animation::method_track_get_params(int p_track, int p_key_idx) const {

	ERR_FAIL_INDEX_V(p_track, tracks.size(), Vector<Variant>());
	Track *t = tracks[p_track];
	ERR_FAIL_COND_V(t->type != TYPE_METHOD, Vector<Variant>());

	MethodTrack *pm = static_cast<MethodTrack *>(t);

	ERR_FAIL_INDEX_V(p_key_idx, pm->methods.size(), Vector<Variant>());

	const MethodKey &mk = pm->methods[p_key_idx];

	return mk.params;
}
StringName Animation::method_track_get_name(int p_track, int p_key_idx) const {

	ERR_FAIL_INDEX_V(p_track, tracks.size(), StringName());
	Track *t = tracks[p_track];
	ERR_FAIL_COND_V(t->type != TYPE_METHOD, StringName());

	MethodTrack *pm = static_cast<MethodTrack *>(t);

	ERR_FAIL_INDEX_V(p_key_idx, pm->methods.size(), StringName());

	return pm->methods[p_key_idx].method;
}

void Animation::set_length(float p_length) {

	ERR_FAIL_COND(length < 0);
	length = p_length;
	emit_changed();
}
float Animation::get_length() const {

	return length;
}

void Animation::set_loop(bool p_enabled) {

	loop = p_enabled;
	emit_changed();
}
bool Animation::has_loop() const {

	return loop;
}

void Animation::track_move_up(int p_track) {

	if (p_track >= 0 && p_track < (tracks.size() - 1)) {

		SWAP(tracks[p_track], tracks[p_track + 1]);
	}

	emit_changed();
}

void Animation::track_set_imported(int p_track, bool p_imported) {

	ERR_FAIL_INDEX(p_track, tracks.size());
	tracks[p_track]->imported = p_imported;
}

bool Animation::track_is_imported(int p_track) const {

	ERR_FAIL_INDEX_V(p_track, tracks.size(), false);
	return tracks[p_track]->imported;
}

void Animation::track_move_down(int p_track) {

	if (p_track > 0 && p_track < tracks.size()) {

		SWAP(tracks[p_track], tracks[p_track - 1]);
	}
	emit_changed();
}

void Animation::set_step(float p_step) {

	step = p_step;
	emit_changed();
}

float Animation::get_step() const {

	return step;
}

void Animation::_bind_methods() {

	ClassDB::bind_method(D_METHOD("add_track", "type", "at_pos"), &Animation::add_track, DEFVAL(-1));
	ClassDB::bind_method(D_METHOD("remove_track", "idx"), &Animation::remove_track);
	ClassDB::bind_method(D_METHOD("get_track_count"), &Animation::get_track_count);
	ClassDB::bind_method(D_METHOD("track_get_type", "idx"), &Animation::track_get_type);
	ClassDB::bind_method(D_METHOD("track_get_path", "idx"), &Animation::track_get_path);
	ClassDB::bind_method(D_METHOD("track_set_path", "idx", "path"), &Animation::track_set_path);
	ClassDB::bind_method(D_METHOD("find_track", "path"), &Animation::find_track);

	ClassDB::bind_method(D_METHOD("track_move_up", "idx"), &Animation::track_move_up);
	ClassDB::bind_method(D_METHOD("track_move_down", "idx"), &Animation::track_move_down);

	ClassDB::bind_method(D_METHOD("track_set_imported", "idx", "imported"), &Animation::track_set_imported);
	ClassDB::bind_method(D_METHOD("track_is_imported", "idx"), &Animation::track_is_imported);

	ClassDB::bind_method(D_METHOD("transform_track_insert_key", "idx", "time", "loc", "rot", "scale"), &Animation::transform_track_insert_key);
	ClassDB::bind_method(D_METHOD("track_insert_key", "idx", "time", "key", "transition"), &Animation::track_insert_key, DEFVAL(1));
	ClassDB::bind_method(D_METHOD("track_remove_key", "idx", "key_idx"), &Animation::track_remove_key);
	ClassDB::bind_method(D_METHOD("track_remove_key_at_pos", "idx", "pos"), &Animation::track_remove_key_at_pos);
	ClassDB::bind_method(D_METHOD("track_set_key_value", "idx", "key", "value"), &Animation::track_set_key_value);
	ClassDB::bind_method(D_METHOD("track_set_key_transition", "idx", "key_idx", "transition"), &Animation::track_set_key_transition);
	ClassDB::bind_method(D_METHOD("track_get_key_transition", "idx", "key_idx"), &Animation::track_get_key_transition);

	ClassDB::bind_method(D_METHOD("track_get_key_count", "idx"), &Animation::track_get_key_count);
	ClassDB::bind_method(D_METHOD("track_get_key_value", "idx", "key_idx"), &Animation::track_get_key_value);
	ClassDB::bind_method(D_METHOD("track_get_key_time", "idx", "key_idx"), &Animation::track_get_key_time);
	ClassDB::bind_method(D_METHOD("track_find_key", "idx", "time", "exact"), &Animation::track_find_key, DEFVAL(false));

	ClassDB::bind_method(D_METHOD("track_set_interpolation_type", "idx", "interpolation"), &Animation::track_set_interpolation_type);
	ClassDB::bind_method(D_METHOD("track_get_interpolation_type", "idx"), &Animation::track_get_interpolation_type);

	ClassDB::bind_method(D_METHOD("track_set_interpolation_loop_wrap", "idx", "interpolation"), &Animation::track_set_interpolation_loop_wrap);
	ClassDB::bind_method(D_METHOD("track_get_interpolation_loop_wrap", "idx"), &Animation::track_get_interpolation_loop_wrap);

	ClassDB::bind_method(D_METHOD("transform_track_interpolate", "idx", "time_sec"), &Animation::_transform_track_interpolate);
	ClassDB::bind_method(D_METHOD("value_track_set_update_mode", "idx", "mode"), &Animation::value_track_set_update_mode);
	ClassDB::bind_method(D_METHOD("value_track_get_update_mode", "idx"), &Animation::value_track_get_update_mode);

	ClassDB::bind_method(D_METHOD("value_track_get_key_indices", "idx", "time_sec", "delta"), &Animation::_value_track_get_key_indices);

	ClassDB::bind_method(D_METHOD("method_track_get_key_indices", "idx", "time_sec", "delta"), &Animation::_method_track_get_key_indices);
	ClassDB::bind_method(D_METHOD("method_track_get_name", "idx", "key_idx"), &Animation::method_track_get_name);
	ClassDB::bind_method(D_METHOD("method_track_get_params", "idx", "key_idx"), &Animation::method_track_get_params);

	ClassDB::bind_method(D_METHOD("set_length", "time_sec"), &Animation::set_length);
	ClassDB::bind_method(D_METHOD("get_length"), &Animation::get_length);

	ClassDB::bind_method(D_METHOD("set_loop", "enabled"), &Animation::set_loop);
	ClassDB::bind_method(D_METHOD("has_loop"), &Animation::has_loop);

	ClassDB::bind_method(D_METHOD("set_step", "size_sec"), &Animation::set_step);
	ClassDB::bind_method(D_METHOD("get_step"), &Animation::get_step);

	ClassDB::bind_method(D_METHOD("clear"), &Animation::clear);

	BIND_CONSTANT(TYPE_VALUE);
	BIND_CONSTANT(TYPE_TRANSFORM);
	BIND_CONSTANT(TYPE_METHOD);

	BIND_CONSTANT(INTERPOLATION_NEAREST);
	BIND_CONSTANT(INTERPOLATION_LINEAR);
	BIND_CONSTANT(INTERPOLATION_CUBIC);

	BIND_CONSTANT(UPDATE_CONTINUOUS);
	BIND_CONSTANT(UPDATE_DISCRETE);
	BIND_CONSTANT(UPDATE_TRIGGER);
}

void Animation::clear() {

	for (int i = 0; i < tracks.size(); i++)
		memdelete(tracks[i]);
	tracks.clear();
	loop = false;
	length = 1;
}

bool Animation::_transform_track_optimize_key(const TKey<TransformKey> &t0, const TKey<TransformKey> &t1, const TKey<TransformKey> &t2, float p_alowed_linear_err, float p_alowed_angular_err, float p_max_optimizable_angle, const Vector3 &p_norm) {

	real_t c = (t1.time - t0.time) / (t2.time - t0.time);
	real_t t[3] = { -1, -1, -1 };

	{ //translation

		const Vector3 &v0 = t0.value.loc;
		const Vector3 &v1 = t1.value.loc;
		const Vector3 &v2 = t2.value.loc;

		if (v0.distance_to(v2) < CMP_EPSILON) {
			//0 and 2 are close, let's see if 1 is close
			if (v0.distance_to(v1) > CMP_EPSILON) {
				//not close, not optimizable
				return false;
			}

		} else {

			Vector3 pd = (v2 - v0);
			float d0 = pd.dot(v0);
			float d1 = pd.dot(v1);
			float d2 = pd.dot(v2);
			if (d1 < d0 || d1 > d2) {
				return false;
			}

			Vector3 s[2] = { v0, v2 };
			real_t d = Geometry::get_closest_point_to_segment(v1, s).distance_to(v1);

			if (d > pd.length() * p_alowed_linear_err) {
				return false; //beyond allowed error for colinearity
			}

			if (p_norm != Vector3() && Math::acos(pd.normalized().dot(p_norm)) > p_alowed_angular_err)
				return false;

			t[0] = (d1 - d0) / (d2 - d0);
		}
	}

	{ //rotation

		const Quat &q0 = t0.value.rot;
		const Quat &q1 = t1.value.rot;
		const Quat &q2 = t2.value.rot;

		//localize both to rotation from q0

		if ((q0 - q2).length() < CMP_EPSILON) {

			if ((q0 - q1).length() > CMP_EPSILON)
				return false;

		} else {

			Quat r02 = (q0.inverse() * q2).normalized();
			Quat r01 = (q0.inverse() * q1).normalized();

			Vector3 v02, v01;
			real_t a02, a01;

			r02.get_axis_angle(v02, a02);
			r01.get_axis_angle(v01, a01);

			if (Math::abs(a02) > p_max_optimizable_angle)
				return false;

			if (v01.dot(v02) < 0) {
				//make sure both rotations go the same way to compare
				v02 = -v02;
				a02 = -a02;
			}

			real_t err_01 = Math::acos(v01.normalized().dot(v02.normalized())) / Math_PI;
			if (err_01 > p_alowed_angular_err) {
				//not rotating in the same axis
				return false;
			}

			if (a01 * a02 < 0) {
				//not rotating in the same direction
				return false;
			}

			real_t tr = a01 / a02;
			if (tr < 0 || tr > 1)
				return false; //rotating too much or too less

			t[1] = tr;
		}
	}

	{ //scale

		const Vector3 &v0 = t0.value.scale;
		const Vector3 &v1 = t1.value.scale;
		const Vector3 &v2 = t2.value.scale;

		if (v0.distance_to(v2) < CMP_EPSILON) {
			//0 and 2 are close, let's see if 1 is close
			if (v0.distance_to(v1) > CMP_EPSILON) {
				//not close, not optimizable
				return false;
			}

		} else {

			Vector3 pd = (v2 - v0);
			float d0 = pd.dot(v0);
			float d1 = pd.dot(v1);
			float d2 = pd.dot(v2);
			if (d1 < d0 || d1 > d2) {
				return false; //beyond segment range
			}

			Vector3 s[2] = { v0, v2 };
			real_t d = Geometry::get_closest_point_to_segment(v1, s).distance_to(v1);

			if (d > pd.length() * p_alowed_linear_err) {
				return false; //beyond allowed error for colinearity
			}

			t[2] = (d1 - d0) / (d2 - d0);
		}
	}

	bool erase = false;
	if (t[0] == -1 && t[1] == -1 && t[2] == -1) {

		erase = true;
	} else {

		erase = true;
		real_t lt = -1;
		for (int j = 0; j < 3; j++) {
			//search for t on first, one must be it
			if (t[j] != -1) {
				lt = t[j]; //official t
				//validate rest
				for (int k = j + 1; k < 3; k++) {
					if (t[k] == -1)
						continue;

					if (Math::abs(lt - t[k]) > p_alowed_linear_err) {
						erase = false;
						break;
					}
				}
				break;
			}
		}

		ERR_FAIL_COND_V(lt == -1, false);

		if (erase) {

			if (Math::abs(lt - c) > p_alowed_linear_err) {
				//todo, evaluate changing the transition if this fails?
				//this could be done as a second pass and would be
				//able to optimize more
				erase = false;
			} else {

				//print_line(itos(i)+"because of interp");
			}
		}
	}

	return erase;
}

void Animation::_transform_track_optimize(int p_idx, float p_alowed_linear_err, float p_alowed_angular_err, float p_max_optimizable_angle) {

	ERR_FAIL_INDEX(p_idx, tracks.size());
	ERR_FAIL_COND(tracks[p_idx]->type != TYPE_TRANSFORM);
	TransformTrack *tt = static_cast<TransformTrack *>(tracks[p_idx]);
	bool prev_erased = false;
	TKey<TransformKey> first_erased;

	Vector3 norm;

	for (int i = 1; i < tt->transforms.size() - 1; i++) {

		TKey<TransformKey> &t0 = tt->transforms[i - 1];
		TKey<TransformKey> &t1 = tt->transforms[i];
		TKey<TransformKey> &t2 = tt->transforms[i + 1];

		bool erase = _transform_track_optimize_key(t0, t1, t2, p_alowed_linear_err, p_alowed_angular_err, p_max_optimizable_angle, norm);
		if (erase && !prev_erased) {
			norm = (t2.value.loc - t1.value.loc).normalized();
		}

		if (prev_erased && !_transform_track_optimize_key(t0, first_erased, t2, p_alowed_linear_err, p_alowed_angular_err, p_max_optimizable_angle, norm)) {
			//avoid error to go beyond first erased key
			erase = false;
		}

		if (erase) {

			if (!prev_erased) {
				first_erased = t1;
				prev_erased = true;
			}

			tt->transforms.remove(i);
			i--;

		} else {
			prev_erased = false;
			norm = Vector3();
		}
	}
}

void Animation::optimize(float p_allowed_linear_err, float p_allowed_angular_err, float p_angle_max) {

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

		if (tracks[i]->type == TYPE_TRANSFORM)
			_transform_track_optimize(i, p_allowed_linear_err, p_allowed_angular_err, p_angle_max);
	}
}

Animation::Animation() {

	step = 0.1;
	loop = false;
	length = 1;
}

Animation::~Animation() {

	for (int i = 0; i < tracks.size(); i++)
		memdelete(tracks[i]);
}