text: /*************************************************************************/
  /*  editor_scene_importer_gltf.cpp                                       */
  /*************************************************************************/
  /*                       This file is part of:                           */
  /*                           Valjang Engine                                */
  /*                      http://Valjang.fr                          */
  /*************************************************************************/
  /* Copyright (c) 2007-2020 Valjang.                 */
  /* Copyright (c) 2014-2020 Valjang 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 "editor_scene_importer_gltf.h"
  
  #include "core/crypto/crypto_core.h"
  #include "core/io/json.h"
  #include "core/math/disjoint_set.h"
  #include "core/math/math_defs.h"
  #include "core/os/file_access.h"
  #include "core/os/os.h"
  #include "modules/regex/regex.h"
  #include "scene/3d/bone_attachment_3d.h"
  #include "scene/3d/camera_3d.h"
  #include "scene/3d/mesh_instance_3d.h"
  #include "scene/animation/animation_player.h"
  #include "scene/resources/surface_tool.h"
  
  uint32_t EditorSceneImporterGLTF::get_import_flags() const {
  	return IMPORT_SCENE | IMPORT_ANIMATION;
  }
  
  void EditorSceneImporterGLTF::get_extensions(List<String> *r_extensions) const {
  	r_extensions->push_back("gltf");
  	r_extensions->push_back("glb");
  }
  
  Error EditorSceneImporterGLTF::_parse_json(const String &p_path, GLTFState &state) {
  	Error err;
  	FileAccessRef f = FileAccess::open(p_path, FileAccess::READ, &err);
  	if (!f) {
  		return err;
  	}
  
  	Vector<uint8_t> array;
  	array.resize(f->get_len());
  	f->get_buffer(array.ptrw(), array.size());
  	String text;
  	text.parse_utf8((const char *)array.ptr(), array.size());
  
  	String err_txt;
  	int err_line;
  	Variant v;
  	err = JSON::parse(text, v, err_txt, err_line);
  	if (err != OK) {
  		_err_print_error("", p_path.utf8().get_data(), err_line, err_txt.utf8().get_data(), ERR_HANDLER_SCRIPT);
  		return err;
  	}
  	state.json = v;
  
  	return OK;
  }
  
  Error EditorSceneImporterGLTF::_parse_glb(const String &p_path, GLTFState &state) {
  	Error err;
  	FileAccessRef f = FileAccess::open(p_path, FileAccess::READ, &err);
  	if (!f) {
  		return err;
  	}
  
  	uint32_t magic = f->get_32();
  	ERR_FAIL_COND_V(magic != 0x46546C67, ERR_FILE_UNRECOGNIZED); //glTF
  	f->get_32(); // version
  	f->get_32(); // length
  
  	uint32_t chunk_length = f->get_32();
  	uint32_t chunk_type = f->get_32();
  
  	ERR_FAIL_COND_V(chunk_type != 0x4E4F534A, ERR_PARSE_ERROR); //JSON
  	Vector<uint8_t> json_data;
  	json_data.resize(chunk_length);
  	uint32_t len = f->get_buffer(json_data.ptrw(), chunk_length);
  	ERR_FAIL_COND_V(len != chunk_length, ERR_FILE_CORRUPT);
  
  	String text;
  	text.parse_utf8((const char *)json_data.ptr(), json_data.size());
  
  	String err_txt;
  	int err_line;
  	Variant v;
  	err = JSON::parse(text, v, err_txt, err_line);
  	if (err != OK) {
  		_err_print_error("", p_path.utf8().get_data(), err_line, err_txt.utf8().get_data(), ERR_HANDLER_SCRIPT);
  		return err;
  	}
  
  	state.json = v;
  
  	//data?
  
  	chunk_length = f->get_32();
  	chunk_type = f->get_32();
  
  	if (f->eof_reached()) {
  		return OK; //all good
  	}
  
  	ERR_FAIL_COND_V(chunk_type != 0x004E4942, ERR_PARSE_ERROR); //BIN
  
  	state.glb_data.resize(chunk_length);
  	len = f->get_buffer(state.glb_data.ptrw(), chunk_length);
  	ERR_FAIL_COND_V(len != chunk_length, ERR_FILE_CORRUPT);
  
  	return OK;
  }
  
  static Vector3 _arr_to_vec3(const Array &p_array) {
  	ERR_FAIL_COND_V(p_array.size() != 3, Vector3());
  	return Vector3(p_array[0], p_array[1], p_array[2]);
  }
  
  static Quat _arr_to_quat(const Array &p_array) {
  	ERR_FAIL_COND_V(p_array.size() != 4, Quat());
  	return Quat(p_array[0], p_array[1], p_array[2], p_array[3]);
  }
  
  static Transform _arr_to_xform(const Array &p_array) {
  	ERR_FAIL_COND_V(p_array.size() != 16, Transform());
  
  	Transform xform;
  	xform.basis.set_axis(Vector3::AXIS_X, Vector3(p_array[0], p_array[1], p_array[2]));
  	xform.basis.set_axis(Vector3::AXIS_Y, Vector3(p_array[4], p_array[5], p_array[6]));
  	xform.basis.set_axis(Vector3::AXIS_Z, Vector3(p_array[8], p_array[9], p_array[10]));
  	xform.set_origin(Vector3(p_array[12], p_array[13], p_array[14]));
  
  	return xform;
  }
  
  String EditorSceneImporterGLTF::_sanitize_scene_name(const String &name) {
  	RegEx regex("([^a-zA-Z0-9_ -]+)");
  	String p_name = regex.sub(name, "", true);
  	return p_name;
  }
  
  String EditorSceneImporterGLTF::_gen_unique_name(GLTFState &state, const String &p_name) {
  	const String s_name = _sanitize_scene_name(p_name);
  
  	String name;
  	int index = 1;
  	while (true) {
  		name = s_name;
  
  		if (index > 1) {
  			name += " " + itos(index);
  		}
  		if (!state.unique_names.has(name)) {
  			break;
  		}
  		index++;
  	}
  
  	state.unique_names.insert(name);
  
  	return name;
  }
  
  String EditorSceneImporterGLTF::_sanitize_bone_name(const String &name) {
  	String p_name = name.camelcase_to_underscore(true);
  
  	RegEx pattern_del("([^a-zA-Z0-9_ ])+");
  	p_name = pattern_del.sub(p_name, "", true);
  
  	RegEx pattern_nospace(" +");
  	p_name = pattern_nospace.sub(p_name, "_", true);
  
  	RegEx pattern_multiple("_+");
  	p_name = pattern_multiple.sub(p_name, "_", true);
  
  	RegEx pattern_padded("0+(\\d+)");
  	p_name = pattern_padded.sub(p_name, "$1", true);
  
  	return p_name;
  }
  
  String EditorSceneImporterGLTF::_gen_unique_bone_name(GLTFState &state, const GLTFSkeletonIndex skel_i, const String &p_name) {
  	const String s_name = _sanitize_bone_name(p_name);
  
  	String name;
  	int index = 1;
  	while (true) {
  		name = s_name;
  
  		if (index > 1) {
  			name += "_" + itos(index);
  		}
  		if (!state.skeletons[skel_i].unique_names.has(name)) {
  			break;
  		}
  		index++;
  	}
  
  	state.skeletons.write[skel_i].unique_names.insert(name);
  
  	return name;
  }
  
  Error EditorSceneImporterGLTF::_parse_scenes(GLTFState &state) {
  	ERR_FAIL_COND_V(!state.json.has("scenes"), ERR_FILE_CORRUPT);
  	const Array &scenes = state.json["scenes"];
  	int loaded_scene = 0;
  	if (state.json.has("scene")) {
  		loaded_scene = state.json["scene"];
  	} else {
  		WARN_PRINT("The load-time scene is not defined in the glTF2 file. Picking the first scene.");
  	}
  
  	if (scenes.size()) {
  		ERR_FAIL_COND_V(loaded_scene >= scenes.size(), ERR_FILE_CORRUPT);
  		const Dictionary &s = scenes[loaded_scene];
  		ERR_FAIL_COND_V(!s.has("nodes"), ERR_UNAVAILABLE);
  		const Array &nodes = s["nodes"];
  		for (int j = 0; j < nodes.size(); j++) {
  			state.root_nodes.push_back(nodes[j]);
  		}
  
  		if (s.has("name") && s["name"] != "") {
  			state.scene_name = _gen_unique_name(state, s["name"]);
  		} else {
  			state.scene_name = _gen_unique_name(state, "Scene");
  		}
  	}
  
  	return OK;
  }
  
  Error EditorSceneImporterGLTF::_parse_nodes(GLTFState &state) {
  	ERR_FAIL_COND_V(!state.json.has("nodes"), ERR_FILE_CORRUPT);
  	const Array &nodes = state.json["nodes"];
  	for (int i = 0; i < nodes.size(); i++) {
  		GLTFNode *node = memnew(GLTFNode);
  		const Dictionary &n = nodes[i];
  
  		if (n.has("name")) {
  			node->name = n["name"];
  		}
  		if (n.has("camera")) {
  			node->camera = n["camera"];
  		}
  		if (n.has("mesh")) {
  			node->mesh = n["mesh"];
  		}
  		if (n.has("skin")) {
  			node->skin = n["skin"];
  		}
  		if (n.has("matrix")) {
  			node->xform = _arr_to_xform(n["matrix"]);
  
  		} else {
  			if (n.has("translation")) {
  				node->translation = _arr_to_vec3(n["translation"]);
  			}
  			if (n.has("rotation")) {
  				node->rotation = _arr_to_quat(n["rotation"]);
  			}
  			if (n.has("scale")) {
  				node->scale = _arr_to_vec3(n["scale"]);
  			}
  
  			node->xform.basis.set_quat_scale(node->rotation, node->scale);
  			node->xform.origin = node->translation;
  		}
  		if (n.has("extensions")) {
  			Dictionary extensions = n["extensions"];
  			if (extensions.has("KHR_lights_punctual")) {
  				Dictionary lights_punctual = extensions["KHR_lights_punctual"];
  				if (lights_punctual.has("light")) {
  					GLTFLightIndex light = lights_punctual["light"];
  					node->light = light;
  				}
  			}
  		}
  		if (n.has("children")) {
  			const Array &children = n["children"];
  			for (int j = 0; j < children.size(); j++) {
  				node->children.push_back(children[j]);
  			}
  		}
  
  		state.nodes.push_back(node);
  	}
  
  	// build the hierarchy
  	for (GLTFNodeIndex node_i = 0; node_i < state.nodes.size(); node_i++) {
  		for (int j = 0; j < state.nodes[node_i]->children.size(); j++) {
  			GLTFNodeIndex child_i = state.nodes[node_i]->children[j];
  
  			ERR_FAIL_INDEX_V(child_i, state.nodes.size(), ERR_FILE_CORRUPT);
  			ERR_CONTINUE(state.nodes[child_i]->parent != -1); //node already has a parent, wtf.
  
  			state.nodes[child_i]->parent = node_i;
  		}
  	}
  
  	_compute_node_heights(state);
  
  	return OK;
  }
  
  void EditorSceneImporterGLTF::_compute_node_heights(GLTFState &state) {
  	state.root_nodes.clear();
  	for (GLTFNodeIndex node_i = 0; node_i < state.nodes.size(); ++node_i) {
  		GLTFNode *node = state.nodes[node_i];
  		node->height = 0;
  
  		GLTFNodeIndex current_i = node_i;
  		while (current_i >= 0) {
  			const GLTFNodeIndex parent_i = state.nodes[current_i]->parent;
  			if (parent_i >= 0) {
  				++node->height;
  			}
  			current_i = parent_i;
  		}
  
  		if (node->height == 0) {
  			state.root_nodes.push_back(node_i);
  		}
  	}
  }
  
  static Vector<uint8_t> _parse_base64_uri(const String &uri) {
  	int start = uri.find(",");
  	ERR_FAIL_COND_V(start == -1, Vector<uint8_t>());
  
  	CharString substr = uri.right(start + 1).ascii();
  
  	int strlen = substr.length();
  
  	Vector<uint8_t> buf;
  	buf.resize(strlen / 4 * 3 + 1 + 1);
  
  	size_t len = 0;
  	ERR_FAIL_COND_V(CryptoCore::b64_decode(buf.ptrw(), buf.size(), &len, (unsigned char *)substr.get_data(), strlen) != OK, Vector<uint8_t>());
  
  	buf.resize(len);
  
  	return buf;
  }
  
  Error EditorSceneImporterGLTF::_parse_buffers(GLTFState &state, const String &p_base_path) {
  	if (!state.json.has("buffers")) {
  		return OK;
  	}
  
  	const Array &buffers = state.json["buffers"];
  	for (GLTFBufferIndex i = 0; i < buffers.size(); i++) {
  		if (i == 0 && state.glb_data.size()) {
  			state.buffers.push_back(state.glb_data);
  
  		} else {
  			const Dictionary &buffer = buffers[i];
  			if (buffer.has("uri")) {
  				Vector<uint8_t> buffer_data;
  				String uri = buffer["uri"];
  
  				if (uri.findn("data:application/octet-stream;base64") == 0) {
  					//embedded data
  					buffer_data = _parse_base64_uri(uri);
  				} else {
  					uri = p_base_path.plus_file(uri).replace("\\", "/"); //fix for windows
  					buffer_data = FileAccess::get_file_as_array(uri);
  					ERR_FAIL_COND_V(buffer.size() == 0, ERR_PARSE_ERROR);
  				}
  
  				ERR_FAIL_COND_V(!buffer.has("byteLength"), ERR_PARSE_ERROR);
  				int byteLength = buffer["byteLength"];
  				ERR_FAIL_COND_V(byteLength < buffer_data.size(), ERR_PARSE_ERROR);
  				state.buffers.push_back(buffer_data);
  			}
  		}
  	}
  
  	print_verbose("glTF: Total buffers: " + itos(state.buffers.size()));
  
  	return OK;
  }
  
  Error EditorSceneImporterGLTF::_parse_buffer_views(GLTFState &state) {
  	ERR_FAIL_COND_V(!state.json.has("bufferViews"), ERR_FILE_CORRUPT);
  	const Array &buffers = state.json["bufferViews"];
  	for (GLTFBufferViewIndex i = 0; i < buffers.size(); i++) {
  		const Dictionary &d = buffers[i];
  
  		GLTFBufferView buffer_view;
  
  		ERR_FAIL_COND_V(!d.has("buffer"), ERR_PARSE_ERROR);
  		buffer_view.buffer = d["buffer"];
  		ERR_FAIL_COND_V(!d.has("byteLength"), ERR_PARSE_ERROR);
  		buffer_view.byte_length = d["byteLength"];
  
  		if (d.has("byteOffset")) {
  			buffer_view.byte_offset = d["byteOffset"];
  		}
  
  		if (d.has("byteStride")) {
  			buffer_view.byte_stride = d["byteStride"];
  		}
  
  		if (d.has("target")) {
  			const int target = d["target"];
  			buffer_view.indices = target == ELEMENT_ARRAY_BUFFER;
  		}
  
  		state.buffer_views.push_back(buffer_view);
  	}
  
  	print_verbose("glTF: Total buffer views: " + itos(state.buffer_views.size()));
  
  	return OK;
  }
  
  EditorSceneImporterGLTF::GLTFType EditorSceneImporterGLTF::_get_type_from_str(const String &p_string) {
  	if (p_string == "SCALAR") {
  		return TYPE_SCALAR;
  	}
  
  	if (p_string == "VEC2") {
  		return TYPE_VEC2;
  	}
  	if (p_string == "VEC3") {
  		return TYPE_VEC3;
  	}
  	if (p_string == "VEC4") {
  		return TYPE_VEC4;
  	}
  
  	if (p_string == "MAT2") {
  		return TYPE_MAT2;
  	}
  	if (p_string == "MAT3") {
  		return TYPE_MAT3;
  	}
  	if (p_string == "MAT4") {
  		return TYPE_MAT4;
  	}
  
  	ERR_FAIL_V(TYPE_SCALAR);
  }
  
  Error EditorSceneImporterGLTF::_parse_accessors(GLTFState &state) {
  	ERR_FAIL_COND_V(!state.json.has("accessors"), ERR_FILE_CORRUPT);
  	const Array &accessors = state.json["accessors"];
  	for (GLTFAccessorIndex i = 0; i < accessors.size(); i++) {
  		const Dictionary &d = accessors[i];
  
  		GLTFAccessor accessor;
  
  		ERR_FAIL_COND_V(!d.has("componentType"), ERR_PARSE_ERROR);
  		accessor.component_type = d["componentType"];
  		ERR_FAIL_COND_V(!d.has("count"), ERR_PARSE_ERROR);
  		accessor.count = d["count"];
  		ERR_FAIL_COND_V(!d.has("type"), ERR_PARSE_ERROR);
  		accessor.type = _get_type_from_str(d["type"]);
  
  		if (d.has("bufferView")) {
  			accessor.buffer_view = d["bufferView"]; //optional because it may be sparse...
  		}
  
  		if (d.has("byteOffset")) {
  			accessor.byte_offset = d["byteOffset"];
  		}
  
  		if (d.has("max")) {
  			accessor.max = d["max"];
  		}
  
  		if (d.has("min")) {
  			accessor.min = d["min"];
  		}
  
  		if (d.has("sparse")) {
  			//eeh..
  
  			const Dictionary &s = d["sparse"];
  
  			ERR_FAIL_COND_V(!s.has("count"), ERR_PARSE_ERROR);
  			accessor.sparse_count = s["count"];
  			ERR_FAIL_COND_V(!s.has("indices"), ERR_PARSE_ERROR);
  			const Dictionary &si = s["indices"];
  
  			ERR_FAIL_COND_V(!si.has("bufferView"), ERR_PARSE_ERROR);
  			accessor.sparse_indices_buffer_view = si["bufferView"];
  			ERR_FAIL_COND_V(!si.has("componentType"), ERR_PARSE_ERROR);
  			accessor.sparse_indices_component_type = si["componentType"];
  
  			if (si.has("byteOffset")) {
  				accessor.sparse_indices_byte_offset = si["byteOffset"];
  			}
  
  			ERR_FAIL_COND_V(!s.has("values"), ERR_PARSE_ERROR);
  			const Dictionary &sv = s["values"];
  
  			ERR_FAIL_COND_V(!sv.has("bufferView"), ERR_PARSE_ERROR);
  			accessor.sparse_values_buffer_view = sv["bufferView"];
  			if (sv.has("byteOffset")) {
  				accessor.sparse_values_byte_offset = sv["byteOffset"];
  			}
  		}
  
  		state.accessors.push_back(accessor);
  	}
  
  	print_verbose("glTF: Total accessors: " + itos(state.accessors.size()));
  
  	return OK;
  }
  
  String EditorSceneImporterGLTF::_get_component_type_name(const uint32_t p_component) {
  	switch (p_component) {
  		case COMPONENT_TYPE_BYTE:
  			return "Byte";
  		case COMPONENT_TYPE_UNSIGNED_BYTE:
  			return "UByte";
  		case COMPONENT_TYPE_SHORT:
  			return "Short";
  		case COMPONENT_TYPE_UNSIGNED_SHORT:
  			return "UShort";
  		case COMPONENT_TYPE_INT:
  			return "Int";
  		case COMPONENT_TYPE_FLOAT:
  			return "Float";
  	}
  
  	return "<Error>";
  }
  
  String EditorSceneImporterGLTF::_get_type_name(const GLTFType p_component) {
  	static const char *names[] = {
  		"float",
  		"vec2",
  		"vec3",
  		"vec4",
  		"mat2",
  		"mat3",
  		"mat4"
  	};
  
  	return names[p_component];
  }
  
  Error EditorSceneImporterGLTF::_decode_buffer_view(GLTFState &state, double *dst, const GLTFBufferViewIndex p_buffer_view, const int skip_every, const int skip_bytes, const int element_size, const int count, const GLTFType type, const int component_count, const int component_type, const int component_size, const bool normalized, const int byte_offset, const bool for_vertex) {
  	const GLTFBufferView &bv = state.buffer_views[p_buffer_view];
  
  	int stride = bv.byte_stride ? bv.byte_stride : element_size;
  	if (for_vertex && stride % 4) {
  		stride += 4 - (stride % 4); //according to spec must be multiple of 4
  	}
  
  	ERR_FAIL_INDEX_V(bv.buffer, state.buffers.size(), ERR_PARSE_ERROR);
  
  	const uint32_t offset = bv.byte_offset + byte_offset;
  	Vector<uint8_t> buffer = state.buffers[bv.buffer]; //copy on write, so no performance hit
  	const uint8_t *bufptr = buffer.ptr();
  
  	//use to debug
  	print_verbose("glTF: type " + _get_type_name(type) + " component type: " + _get_component_type_name(component_type) + " stride: " + itos(stride) + " amount " + itos(count));
  	print_verbose("glTF: accessor offset" + itos(byte_offset) + " view offset: " + itos(bv.byte_offset) + " total buffer len: " + itos(buffer.size()) + " view len " + itos(bv.byte_length));
  
  	const int buffer_end = (stride * (count - 1)) + element_size;
  	ERR_FAIL_COND_V(buffer_end > bv.byte_length, ERR_PARSE_ERROR);
  
  	ERR_FAIL_COND_V((int)(offset + buffer_end) > buffer.size(), ERR_PARSE_ERROR);
  
  	//fill everything as doubles
  
  	for (int i = 0; i < count; i++) {
  		const uint8_t *src = &bufptr[offset + i * stride];
  
  		for (int j = 0; j < component_count; j++) {
  			if (skip_every && j > 0 && (j % skip_every) == 0) {
  				src += skip_bytes;
  			}
  
  			double d = 0;
  
  			switch (component_type) {
  				case COMPONENT_TYPE_BYTE: {
  					int8_t b = int8_t(*src);
  					if (normalized) {
  						d = (double(b) / 128.0);
  					} else {
  						d = double(b);
  					}
  				} break;
  				case COMPONENT_TYPE_UNSIGNED_BYTE: {
  					uint8_t b = *src;
  					if (normalized) {
  						d = (double(b) / 255.0);
  					} else {
  						d = double(b);
  					}
  				} break;
  				case COMPONENT_TYPE_SHORT: {
  					int16_t s = *(int16_t *)src;
  					if (normalized) {
  						d = (double(s) / 32768.0);
  					} else {
  						d = double(s);
  					}
  				} break;
  				case COMPONENT_TYPE_UNSIGNED_SHORT: {
  					uint16_t s = *(uint16_t *)src;
  					if (normalized) {
  						d = (double(s) / 65535.0);
  					} else {
  						d = double(s);
  					}
  
  				} break;
  				case COMPONENT_TYPE_INT: {
  					d = *(int *)src;
  				} break;
  				case COMPONENT_TYPE_FLOAT: {
  					d = *(float *)src;
  				} break;
  			}
  
  			*dst++ = d;
  			src += component_size;
  		}
  	}
  
  	return OK;
  }
  
  int EditorSceneImporterGLTF::_get_component_type_size(const int component_type) {
  	switch (component_type) {
  		case COMPONENT_TYPE_BYTE:
  			return 1;
  			break;
  		case COMPONENT_TYPE_UNSIGNED_BYTE:
  			return 1;
  			break;
  		case COMPONENT_TYPE_SHORT:
  			return 2;
  			break;
  		case COMPONENT_TYPE_UNSIGNED_SHORT:
  			return 2;
  			break;
  		case COMPONENT_TYPE_INT:
  			return 4;
  			break;
  		case COMPONENT_TYPE_FLOAT:
  			return 4;
  			break;
  		default: {
  			ERR_FAIL_V(0);
  		}
  	}
  	return 0;
  }
  
  Vector<double> EditorSceneImporterGLTF::_decode_accessor(GLTFState &state, const GLTFAccessorIndex p_accessor, const bool p_for_vertex) {
  	//spec, for reference:
  	//http://github.com/KhronosGroup/glTF/tree/master/specification/2.0#data-alignment
  
  	ERR_FAIL_INDEX_V(p_accessor, state.accessors.size(), Vector<double>());
  
  	const GLTFAccessor &a = state.accessors[p_accessor];
  
  	const int component_count_for_type[7] = {
  		1, 2, 3, 4, 4, 9, 16
  	};
  
  	const int component_count = component_count_for_type[a.type];
  	const int component_size = _get_component_type_size(a.component_type);
  	ERR_FAIL_COND_V(component_size == 0, Vector<double>());
  	int element_size = component_count * component_size;
  
  	int skip_every = 0;
  	int skip_bytes = 0;
  	//special case of alignments, as described in spec
  	switch (a.component_type) {
  		case COMPONENT_TYPE_BYTE:
  		case COMPONENT_TYPE_UNSIGNED_BYTE: {
  			if (a.type == TYPE_MAT2) {
  				skip_every = 2;
  				skip_bytes = 2;
  				element_size = 8; //override for this case
  			}
  			if (a.type == TYPE_MAT3) {
  				skip_every = 3;
  				skip_bytes = 1;
  				element_size = 12; //override for this case
  			}
  
  		} break;
  		case COMPONENT_TYPE_SHORT:
  		case COMPONENT_TYPE_UNSIGNED_SHORT: {
  			if (a.type == TYPE_MAT3) {
  				skip_every = 6;
  				skip_bytes = 4;
  				element_size = 16; //override for this case
  			}
  		} break;
  		default: {
  		}
  	}
  
  	Vector<double> dst_buffer;
  	dst_buffer.resize(component_count * a.count);
  	double *dst = dst_buffer.ptrw();
  
  	if (a.buffer_view >= 0) {
  		ERR_FAIL_INDEX_V(a.buffer_view, state.buffer_views.size(), Vector<double>());
  
  		const Error err = _decode_buffer_view(state, dst, a.buffer_view, skip_every, skip_bytes, element_size, a.count, a.type, component_count, a.component_type, component_size, a.normalized, a.byte_offset, p_for_vertex);
  		if (err != OK) {
  			return Vector<double>();
  		}
  
  	} else {
  		//fill with zeros, as bufferview is not defined.
  		for (int i = 0; i < (a.count * component_count); i++) {
  			dst_buffer.write[i] = 0;
  		}
  	}
  
  	if (a.sparse_count > 0) {
  		// I could not find any file using this, so this code is so far untested
  		Vector<double> indices;
  		indices.resize(a.sparse_count);
  		const int indices_component_size = _get_component_type_size(a.sparse_indices_component_type);
  
  		Error err = _decode_buffer_view(state, indices.ptrw(), a.sparse_indices_buffer_view, 0, 0, indices_component_size, a.sparse_count, TYPE_SCALAR, 1, a.sparse_indices_component_type, indices_component_size, false, a.sparse_indices_byte_offset, false);
  		if (err != OK) {
  			return Vector<double>();
  		}
  
  		Vector<double> data;
  		data.resize(component_count * a.sparse_count);
  		err = _decode_buffer_view(state, data.ptrw(), a.sparse_values_buffer_view, skip_every, skip_bytes, element_size, a.sparse_count, a.type, component_count, a.component_type, component_size, a.normalized, a.sparse_values_byte_offset, p_for_vertex);
  		if (err != OK) {
  			return Vector<double>();
  		}
  
  		for (int i = 0; i < indices.size(); i++) {
  			const int write_offset = int(indices[i]) * component_count;
  
  			for (int j = 0; j < component_count; j++) {
  				dst[write_offset + j] = data[i * component_count + j];
  			}
  		}
  	}
  
  	return dst_buffer;
  }
  
  Vector<int> EditorSceneImporterGLTF::_decode_accessor_as_ints(GLTFState &state, const GLTFAccessorIndex p_accessor, const bool p_for_vertex) {
  	const Vector<double> attribs = _decode_accessor(state, p_accessor, p_for_vertex);
  	Vector<int> ret;
  
  	if (attribs.size() == 0) {
  		return ret;
  	}
  
  	const double *attribs_ptr = attribs.ptr();
  	const int ret_size = attribs.size();
  	ret.resize(ret_size);
  	{
  		int *w = ret.ptrw();
  		for (int i = 0; i < ret_size; i++) {
  			w[i] = int(attribs_ptr[i]);
  		}
  	}
  	return ret;
  }
  
  Vector<float> EditorSceneImporterGLTF::_decode_accessor_as_floats(GLTFState &state, const GLTFAccessorIndex p_accessor, const bool p_for_vertex) {
  	const Vector<double> attribs = _decode_accessor(state, p_accessor, p_for_vertex);
  	Vector<float> ret;
  
  	if (attribs.size() == 0) {
  		return ret;
  	}
  
  	const double *attribs_ptr = attribs.ptr();
  	const int ret_size = attribs.size();
  	ret.resize(ret_size);
  	{
  		float *w = ret.ptrw();
  		for (int i = 0; i < ret_size; i++) {
  			w[i] = float(attribs_ptr[i]);
  		}
  	}
  	return ret;
  }
  
  Vector<Vector2> EditorSceneImporterGLTF::_decode_accessor_as_vec2(GLTFState &state, const GLTFAccessorIndex p_accessor, const bool p_for_vertex) {
  	const Vector<double> attribs = _decode_accessor(state, p_accessor, p_for_vertex);
  	Vector<Vector2> ret;
  
  	if (attribs.size() == 0) {
  		return ret;
  	}
  
  	ERR_FAIL_COND_V(attribs.size() % 2 != 0, ret);
  	const double *attribs_ptr = attribs.ptr();
  	const int ret_size = attribs.size() / 2;
  	ret.resize(ret_size);
  	{
  		Vector2 *w = ret.ptrw();
  		for (int i = 0; i < ret_size; i++) {
  			w[i] = Vector2(attribs_ptr[i * 2 + 0], attribs_ptr[i * 2 + 1]);
  		}
  	}
  	return ret;
  }
  
  Vector<Vector3> EditorSceneImporterGLTF::_decode_accessor_as_vec3(GLTFState &state, const GLTFAccessorIndex p_accessor, const bool p_for_vertex) {
  	const Vector<double> attribs = _decode_accessor(state, p_accessor, p_for_vertex);
  	Vector<Vector3> ret;
  
  	if (attribs.size() == 0) {
  		return ret;
  	}
  
  	ERR_FAIL_COND_V(attribs.size() % 3 != 0, ret);
  	const double *attribs_ptr = attribs.ptr();
  	const int ret_size = attribs.size() / 3;
  	ret.resize(ret_size);
  	{
  		Vector3 *w = ret.ptrw();
  		for (int i = 0; i < ret_size; i++) {
  			w[i] = Vector3(attribs_ptr[i * 3 + 0], attribs_ptr[i * 3 + 1], attribs_ptr[i * 3 + 2]);
  		}
  	}
  	return ret;
  }
  
  Vector<Color> EditorSceneImporterGLTF::_decode_accessor_as_color(GLTFState &state, const GLTFAccessorIndex p_accessor, const bool p_for_vertex) {
  	const Vector<double> attribs = _decode_accessor(state, p_accessor, p_for_vertex);
  	Vector<Color> ret;
  
  	if (attribs.size() == 0) {
  		return ret;
  	}
  
  	const int type = state.accessors[p_accessor].type;
  	ERR_FAIL_COND_V(!(type == TYPE_VEC3 || type == TYPE_VEC4), ret);
  	int vec_len = 3;
  	if (type == TYPE_VEC4) {
  		vec_len = 4;
  	}
  
  	ERR_FAIL_COND_V(attribs.size() % vec_len != 0, ret);
  	const double *attribs_ptr = attribs.ptr();
  	const int ret_size = attribs.size() / vec_len;
  	ret.resize(ret_size);
  	{
  		Color *w = ret.ptrw();
  		for (int i = 0; i < ret_size; i++) {
  			w[i] = Color(attribs_ptr[i * vec_len + 0], attribs_ptr[i * vec_len + 1], attribs_ptr[i * vec_len + 2], vec_len == 4 ? attribs_ptr[i * 4 + 3] : 1.0);
  		}
  	}
  	return ret;
  }
  
  Vector<Quat> EditorSceneImporterGLTF::_decode_accessor_as_quat(GLTFState &state, const GLTFAccessorIndex p_accessor, const bool p_for_vertex) {
  	const Vector<double> attribs = _decode_accessor(state, p_accessor, p_for_vertex);
  	Vector<Quat> ret;
  
  	if (attribs.size() == 0) {
  		return ret;
  	}
  
  	ERR_FAIL_COND_V(attribs.size() % 4 != 0, ret);
  	const double *attribs_ptr = attribs.ptr();
  	const int ret_size = attribs.size() / 4;
  	ret.resize(ret_size);
  	{
  		for (int i = 0; i < ret_size; i++) {
  			ret.write[i] = Quat(attribs_ptr[i * 4 + 0], attribs_ptr[i * 4 + 1], attribs_ptr[i * 4 + 2], attribs_ptr[i * 4 + 3]).normalized();
  		}
  	}
  	return ret;
  }
  
  Vector<Transform2D> EditorSceneImporterGLTF::_decode_accessor_as_xform2d(GLTFState &state, const GLTFAccessorIndex p_accessor, const bool p_for_vertex) {
  	const Vector<double> attribs = _decode_accessor(state, p_accessor, p_for_vertex);
  	Vector<Transform2D> ret;
  
  	if (attribs.size() == 0) {
  		return ret;
  	}
  
  	ERR_FAIL_COND_V(attribs.size() % 4 != 0, ret);
  	ret.resize(attribs.size() / 4);
  	for (int i = 0; i < ret.size(); i++) {
  		ret.write[i][0] = Vector2(attribs[i * 4 + 0], attribs[i * 4 + 1]);
  		ret.write[i][1] = Vector2(attribs[i * 4 + 2], attribs[i * 4 + 3]);
  	}
  	return ret;
  }
  
  Vector<Basis> EditorSceneImporterGLTF::_decode_accessor_as_basis(GLTFState &state, const GLTFAccessorIndex p_accessor, bool p_for_vertex) {
  	const Vector<double> attribs = _decode_accessor(state, p_accessor, p_for_vertex);
  	Vector<Basis> ret;
  
  	if (attribs.size() == 0) {
  		return ret;
  	}
  
  	ERR_FAIL_COND_V(attribs.size() % 9 != 0, ret);
  	ret.resize(attribs.size() / 9);
  	for (int i = 0; i < ret.size(); i++) {
  		ret.write[i].set_axis(0, Vector3(attribs[i * 9 + 0], attribs[i * 9 + 1], attribs[i * 9 + 2]));
  		ret.write[i].set_axis(1, Vector3(attribs[i * 9 + 3], attribs[i * 9 + 4], attribs[i * 9 + 5]));
  		ret.write[i].set_axis(2, Vector3(attribs[i * 9 + 6], attribs[i * 9 + 7], attribs[i * 9 + 8]));
  	}
  	return ret;
  }
  
  Vector<Transform> EditorSceneImporterGLTF::_decode_accessor_as_xform(GLTFState &state, const GLTFAccessorIndex p_accessor, const bool p_for_vertex) {
  	const Vector<double> attribs = _decode_accessor(state, p_accessor, p_for_vertex);
  	Vector<Transform> ret;
  
  	if (attribs.size() == 0) {
  		return ret;
  	}
  
  	ERR_FAIL_COND_V(attribs.size() % 16 != 0, ret);
  	ret.resize(attribs.size() / 16);
  	for (int i = 0; i < ret.size(); i++) {
  		ret.write[i].basis.set_axis(0, Vector3(attribs[i * 16 + 0], attribs[i * 16 + 1], attribs[i * 16 + 2]));
  		ret.write[i].basis.set_axis(1, Vector3(attribs[i * 16 + 4], attribs[i * 16 + 5], attribs[i * 16 + 6]));
  		ret.write[i].basis.set_axis(2, Vector3(attribs[i * 16 + 8], attribs[i * 16 + 9], attribs[i * 16 + 10]));
  		ret.write[i].set_origin(Vector3(attribs[i * 16 + 12], attribs[i * 16 + 13], attribs[i * 16 + 14]));
  	}
  	return ret;
  }
  
  Error EditorSceneImporterGLTF::_parse_meshes(GLTFState &state) {
  	if (!state.json.has("meshes")) {
  		return OK;
  	}
  
  	bool compress_vert_data = state.import_flags & IMPORT_USE_COMPRESSION;
  	uint32_t mesh_flags = compress_vert_data ? Mesh::ARRAY_COMPRESS_DEFAULT : 0;
  
  	Array meshes = state.json["meshes"];
  	for (GLTFMeshIndex i = 0; i < meshes.size(); i++) {
  		print_verbose("glTF: Parsing mesh: " + itos(i));
  		Dictionary d = meshes[i];
  
  		GLTFMesh mesh;
  		mesh.mesh.instance();
  
  		ERR_FAIL_COND_V(!d.has("primitives"), ERR_PARSE_ERROR);
  
  		Array primitives = d["primitives"];
  		const Dictionary &extras = d.has("extras") ? (Dictionary)d["extras"] : Dictionary();
  
  		for (int j = 0; j < primitives.size(); j++) {
  			Dictionary p = primitives[j];
  
  			Array array;
  			array.resize(Mesh::ARRAY_MAX);
  
  			ERR_FAIL_COND_V(!p.has("attributes"), ERR_PARSE_ERROR);
  
  			Dictionary a = p["attributes"];
  
  			Mesh::PrimitiveType primitive = Mesh::PRIMITIVE_TRIANGLES;
  			if (p.has("mode")) {
  				const int mode = p["mode"];
  				ERR_FAIL_INDEX_V(mode, 7, ERR_FILE_CORRUPT);
  				static const Mesh::PrimitiveType primitives2[7] = {
  					Mesh::PRIMITIVE_POINTS,
  					Mesh::PRIMITIVE_LINES,
  					Mesh::PRIMITIVE_LINES, //loop not supported, should ce converted
  					Mesh::PRIMITIVE_LINES,
  					Mesh::PRIMITIVE_TRIANGLES,
  					Mesh::PRIMITIVE_TRIANGLE_STRIP,
  					Mesh::PRIMITIVE_TRIANGLES, //fan not supported, should be converted
  #ifndef _MSC_VER
  #warning line loop and triangle fan are not supported and need to be converted to lines and triangles
  #endif
  
  				};
  
  				primitive = primitives2[mode];
  			}
  
  			ERR_FAIL_COND_V(!a.has("POSITION"), ERR_PARSE_ERROR);
  			if (a.has("POSITION")) {
  				array[Mesh::ARRAY_VERTEX] = _decode_accessor_as_vec3(state, a["POSITION"], true);
  			}
  			if (a.has("NORMAL")) {
  				array[Mesh::ARRAY_NORMAL] = _decode_accessor_as_vec3(state, a["NORMAL"], true);
  			}
  			if (a.has("TANGENT")) {
  				array[Mesh::ARRAY_TANGENT] = _decode_accessor_as_floats(state, a["TANGENT"], true);
  			}
  			if (a.has("TEXCOORD_0")) {
  				array[Mesh::ARRAY_TEX_UV] = _decode_accessor_as_vec2(state, a["TEXCOORD_0"], true);
  			}
  			if (a.has("TEXCOORD_1")) {
  				array[Mesh::ARRAY_TEX_UV2] = _decode_accessor_as_vec2(state, a["TEXCOORD_1"], true);
  			}
  			if (a.has("COLOR_0")) {
  				array[Mesh::ARRAY_COLOR] = _decode_accessor_as_color(state, a["COLOR_0"], true);
  			}
  			if (a.has("JOINTS_0")) {
  				array[Mesh::ARRAY_BONES] = _decode_accessor_as_ints(state, a["JOINTS_0"], true);
  			}
  			if (a.has("WEIGHTS_0")) {
  				Vector<float> weights = _decode_accessor_as_floats(state, a["WEIGHTS_0"], true);
  				{ //gltf does not seem to normalize the weights for some reason..
  					int wc = weights.size();
  					float *w = weights.ptrw();
  
  					for (int k = 0; k < wc; k += 4) {
  						float total = 0.0;
  						total += w[k + 0];
  						total += w[k + 1];
  						total += w[k + 2];
  						total += w[k + 3];
  						if (total > 0.0) {
  							w[k + 0] /= total;
  							w[k + 1] /= total;
  							w[k + 2] /= total;
  							w[k + 3] /= total;
  						}
  					}
  				}
  				array[Mesh::ARRAY_WEIGHTS] = weights;
  			}
  
  			if (p.has("indices")) {
  				Vector<int> indices = _decode_accessor_as_ints(state, p["indices"], false);
  
  				if (primitive == Mesh::PRIMITIVE_TRIANGLES) {
  					//swap around indices, convert ccw to cw for front face
  
  					const int is = indices.size();
  					int *w = indices.ptrw();
  					for (int k = 0; k < is; k += 3) {
  						SWAP(w[k + 1], w[k + 2]);
  					}
  				}
  				array[Mesh::ARRAY_INDEX] = indices;
  
  			} else if (primitive == Mesh::PRIMITIVE_TRIANGLES) {
  				//generate indices because they need to be swapped for CW/CCW
  				const Vector<Vector3> &vertices = array[Mesh::ARRAY_VERTEX];
  				ERR_FAIL_COND_V(vertices.size() == 0, ERR_PARSE_ERROR);
  				Vector<int> indices;
  				const int vs = vertices.size();
  				indices.resize(vs);
  				{
  					int *w = indices.ptrw();
  					for (int k = 0; k < vs; k += 3) {
  						w[k] = k;
  						w[k + 1] = k + 2;
  						w[k + 2] = k + 1;
  					}
  				}
  				array[Mesh::ARRAY_INDEX] = indices;
  			}
  
  			bool generate_tangents = (primitive == Mesh::PRIMITIVE_TRIANGLES && !a.has("TANGENT") && a.has("TEXCOORD_0") && a.has("NORMAL"));
  
  			if (generate_tangents) {
  				//must generate mikktspace tangents.. ergh..
  				Ref<SurfaceTool> st;
  				st.instance();
  				st->create_from_triangle_arrays(array);
  				st->generate_tangents();
  				array = st->commit_to_arrays();
  			}
  
  			Array morphs;
  			//blend shapes
  			if (p.has("targets")) {
  				print_verbose("glTF: Mesh has targets");
  				const Array &targets = p["targets"];
  
  				//ideally BLEND_SHAPE_MODE_RELATIVE since gltf2 stores in displacement
  				//but it could require a larger refactor?
  				mesh.mesh->set_blend_shape_mode(Mesh::BLEND_SHAPE_MODE_NORMALIZED);
  
  				if (j == 0) {
  					const Array &target_names = extras.has("targetNames") ? (Array)extras["targetNames"] : Array();
  					for (int k = 0; k < targets.size(); k++) {
  						const String name = k < target_names.size() ? (String)target_names[k] : String("morph_") + itos(k);
  						mesh.mesh->add_blend_shape(name);
  					}
  				}
  
  				for (int k = 0; k < targets.size(); k++) {
  					const Dictionary &t = targets[k];
  
  					Array array_copy;
  					array_copy.resize(Mesh::ARRAY_MAX);
  
  					for (int l = 0; l < Mesh::ARRAY_MAX; l++) {
  						array_copy[l] = array[l];
  					}
  
  					array_copy[Mesh::ARRAY_INDEX] = Variant();
  
  					if (t.has("POSITION")) {
  						Vector<Vector3> varr = _decode_accessor_as_vec3(state, t["POSITION"], true);
  						const Vector<Vector3> src_varr = array[Mesh::ARRAY_VERTEX];
  						const int size = src_varr.size();
  						ERR_FAIL_COND_V(size == 0, ERR_PARSE_ERROR);
  						{
  							const int max_idx = varr.size();
  							varr.resize(size);
  
  							Vector3 *w_varr = varr.ptrw();
  							const Vector3 *r_varr = varr.ptr();
  							const Vector3 *r_src_varr = src_varr.ptr();
  							for (int l = 0; l < size; l++) {
  								if (l < max_idx) {
  									w_varr[l] = r_varr[l] + r_src_varr[l];
  								} else {
  									w_varr[l] = r_src_varr[l];
  								}
  							}
  						}
  						array_copy[Mesh::ARRAY_VERTEX] = varr;
  					}
  					if (t.has("NORMAL")) {
  						Vector<Vector3> narr = _decode_accessor_as_vec3(state, t["NORMAL"], true);
  						const Vector<Vector3> src_narr = array[Mesh::ARRAY_NORMAL];
  						int size = src_narr.size();
  						ERR_FAIL_COND_V(size == 0, ERR_PARSE_ERROR);
  						{
  							int max_idx = narr.size();
  							narr.resize(size);
  
  							Vector3 *w_narr = narr.ptrw();
  							const Vector3 *r_narr = narr.ptr();
  							const Vector3 *r_src_narr = src_narr.ptr();
  							for (int l = 0; l < size; l++) {
  								if (l < max_idx) {
  									w_narr[l] = r_narr[l] + r_src_narr[l];
  								} else {
  									w_narr[l] = r_src_narr[l];
  								}
  							}
  						}
  						array_copy[Mesh::ARRAY_NORMAL] = narr;
  					}
  					if (t.has("TANGENT")) {
  						const Vector<Vector3> tangents_v3 = _decode_accessor_as_vec3(state, t["TANGENT"], true);
  						const Vector<float> src_tangents = array[Mesh::ARRAY_TANGENT];
  						ERR_FAIL_COND_V(src_tangents.size() == 0, ERR_PARSE_ERROR);
  
  						Vector<float> tangents_v4;
  
  						{
  							int max_idx = tangents_v3.size();
  
  							int size4 = src_tangents.size();
  							tangents_v4.resize(size4);
  							float *w4 = tangents_v4.ptrw();
  
  							const Vector3 *r3 = tangents_v3.ptr();
  							const float *r4 = src_tangents.ptr();
  
  							for (int l = 0; l < size4 / 4; l++) {
  								if (l < max_idx) {
  									w4[l * 4 + 0] = r3[l].x + r4[l * 4 + 0];
  									w4[l * 4 + 1] = r3[l].y + r4[l * 4 + 1];
  									w4[l * 4 + 2] = r3[l].z + r4[l * 4 + 2];
  								} else {
  									w4[l * 4 + 0] = r4[l * 4 + 0];
  									w4[l * 4 + 1] = r4[l * 4 + 1];
  									w4[l * 4 + 2] = r4[l * 4 + 2];
  								}
  								w4[l * 4 + 3] = r4[l * 4 + 3]; //copy flip value
  							}
  						}
  
  						array_copy[Mesh::ARRAY_TANGENT] = tangents_v4;
  					}
  
  					if (generate_tangents) {
  						Ref<SurfaceTool> st;
  						st.instance();
  						st->create_from_triangle_arrays(array_copy);
  						st->deindex();
  						st->generate_tangents();
  						array_copy = st->commit_to_arrays();
  					}
  
  					morphs.push_back(array_copy);
  				}
  			}
  
  			//just add it
  			mesh.mesh->add_surface_from_arrays(primitive, array, morphs, Dictionary(), mesh_flags);
  
  			if (p.has("material")) {
  				const int material = p["material"];
  				ERR_FAIL_INDEX_V(material, state.materials.size(), ERR_FILE_CORRUPT);
  				const Ref<Material> &mat = state.materials[material];
  
  				mesh.mesh->surface_set_material(mesh.mesh->get_surface_count() - 1, mat);
  			}
  		}
  
  		mesh.blend_weights.resize(mesh.mesh->get_blend_shape_count());
  		for (int32_t weight_i = 0; weight_i < mesh.blend_weights.size(); weight_i++) {
  			mesh.blend_weights.write[weight_i] = 0.0f;
  		}
  
  		if (d.has("weights")) {
  			const Array &weights = d["weights"];
  			ERR_FAIL_COND_V(mesh.blend_weights.size() != weights.size(), ERR_PARSE_ERROR);
  			for (int j = 0; j < weights.size(); j++) {
  				mesh.blend_weights.write[j] = weights[j];
  			}
  		}
  
  		state.meshes.push_back(mesh);
  	}
  
  	print_verbose("glTF: Total meshes: " + itos(state.meshes.size()));
  
  	return OK;
  }
  
  Error EditorSceneImporterGLTF::_parse_images(GLTFState &state, const String &p_base_path) {
  	if (!state.json.has("images")) {
  		return OK;
  	}
  
  	const Array &images = state.json["images"];
  	for (int i = 0; i < images.size(); i++) {
  		const Dictionary &d = images[i];
  
  		String mimetype;
  		if (d.has("mimeType")) {
  			mimetype = d["mimeType"];
  		}
  
  		Vector<uint8_t> data;
  		const uint8_t *data_ptr = nullptr;
  		int data_size = 0;
  
  		if (d.has("uri")) {
  			String uri = d["uri"];
  
  			if (uri.findn("data:application/octet-stream;base64") == 0 ||
  					uri.findn("data:" + mimetype + ";base64") == 0) {
  				//embedded data
  				data = _parse_base64_uri(uri);
  				data_ptr = data.ptr();
  				data_size = data.size();
  			} else {
  				uri = p_base_path.plus_file(uri).replace("\\", "/"); //fix for windows
  				Ref<Texture2D> texture = ResourceLoader::load(uri);
  				state.images.push_back(texture);
  				continue;
  			}
  		}
  
  		if (d.has("bufferView")) {
  			const GLTFBufferViewIndex bvi = d["bufferView"];
  
  			ERR_FAIL_INDEX_V(bvi, state.buffer_views.size(), ERR_PARAMETER_RANGE_ERROR);
  
  			const GLTFBufferView &bv = state.buffer_views[bvi];
  
  			const GLTFBufferIndex bi = bv.buffer;
  			ERR_FAIL_INDEX_V(bi, state.buffers.size(), ERR_PARAMETER_RANGE_ERROR);
  
  			ERR_FAIL_COND_V(bv.byte_offset + bv.byte_length > state.buffers[bi].size(), ERR_FILE_CORRUPT);
  
  			data_ptr = &state.buffers[bi][bv.byte_offset];
  			data_size = bv.byte_length;
  		}
  
  		ERR_FAIL_COND_V(mimetype == "", ERR_FILE_CORRUPT);
  
  		if (mimetype.findn("png") != -1) {
  			//is a png
  			ERR_FAIL_COND_V(Image::_png_mem_loader_func == nullptr, ERR_UNAVAILABLE);
  
  			const Ref<Image> img = Image::_png_mem_loader_func(data_ptr, data_size);
  
  			ERR_FAIL_COND_V(img.is_null(), ERR_FILE_CORRUPT);
  
  			Ref<ImageTexture> t;
  			t.instance();
  			t->create_from_image(img);
  
  			state.images.push_back(t);
  			continue;
  		}
  
  		if (mimetype.findn("jpeg") != -1) {
  			//is a jpg
  			ERR_FAIL_COND_V(Image::_jpg_mem_loader_func == nullptr, ERR_UNAVAILABLE);
  
  			const Ref<Image> img = Image::_jpg_mem_loader_func(data_ptr, data_size);
  
  			ERR_FAIL_COND_V(img.is_null(), ERR_FILE_CORRUPT);
  
  			Ref<ImageTexture> t;
  			t.instance();
  			t->create_from_image(img);
  
  			state.images.push_back(t);
  
  			continue;
  		}
  
  		ERR_FAIL_V(ERR_FILE_CORRUPT);
  	}
  
  	print_verbose("Total images: " + itos(state.images.size()));
  
  	return OK;
  }
  
  Error EditorSceneImporterGLTF::_parse_textures(GLTFState &state) {
  	if (!state.json.has("textures")) {
  		return OK;
  	}
  
  	const Array &textures = state.json["textures"];
  	for (GLTFTextureIndex i = 0; i < textures.size(); i++) {
  		const Dictionary &d = textures[i];
  
  		ERR_FAIL_COND_V(!d.has("source"), ERR_PARSE_ERROR);
  
  		GLTFTexture t;
  		t.src_image = d["source"];
  		state.textures.push_back(t);
  	}
  
  	return OK;
  }
  
  Ref<Texture2D> EditorSceneImporterGLTF::_get_texture(GLTFState &state, const GLTFTextureIndex p_texture) {
  	ERR_FAIL_INDEX_V(p_texture, state.textures.size(), Ref<Texture2D>());
  	const GLTFImageIndex image = state.textures[p_texture].src_image;
  
  	ERR_FAIL_INDEX_V(image, state.images.size(), Ref<Texture2D>());
  
  	return state.images[image];
  }
  
  Error EditorSceneImporterGLTF::_parse_materials(GLTFState &state) {
  	if (!state.json.has("materials")) {
  		return OK;
  	}
  
  	const Array &materials = state.json["materials"];
  	for (GLTFMaterialIndex i = 0; i < materials.size(); i++) {
  		const Dictionary &d = materials[i];
  
  		Ref<StandardMaterial3D> material;
  		material.instance();
  		if (d.has("name")) {
  			material->set_name(d["name"]);
  		}
  
  		if (d.has("pbrMetallicRoughness")) {
  			const Dictionary &mr = d["pbrMetallicRoughness"];
  			if (mr.has("baseColorFactor")) {
  				const Array &arr = mr["baseColorFactor"];
  				ERR_FAIL_COND_V(arr.size() != 4, ERR_PARSE_ERROR);
  				const Color c = Color(arr[0], arr[1], arr[2], arr[3]).to_srgb();
  
  				material->set_albedo(c);
  			}
  
  			if (mr.has("baseColorTexture")) {
  				const Dictionary &bct = mr["baseColorTexture"];
  				if (bct.has("index")) {
  					material->set_texture(StandardMaterial3D::TEXTURE_ALBEDO, _get_texture(state, bct["index"]));
  				}
  				if (!mr.has("baseColorFactor")) {
  					material->set_albedo(Color(1, 1, 1));
  				}
  			}
  
  			if (mr.has("metallicFactor")) {
  				material->set_metallic(mr["metallicFactor"]);
  			} else {
  				material->set_metallic(1.0);
  			}
  
  			if (mr.has("roughnessFactor")) {
  				material->set_roughness(mr["roughnessFactor"]);
  			} else {
  				material->set_roughness(1.0);
  			}
  
  			if (mr.has("metallicRoughnessTexture")) {
  				const Dictionary &bct = mr["metallicRoughnessTexture"];
  				if (bct.has("index")) {
  					const Ref<Texture2D> t = _get_texture(state, bct["index"]);
  					material->set_texture(StandardMaterial3D::TEXTURE_METALLIC, t);
  					material->set_metallic_texture_channel(StandardMaterial3D::TEXTURE_CHANNEL_BLUE);
  					material->set_texture(StandardMaterial3D::TEXTURE_ROUGHNESS, t);
  					material->set_roughness_texture_channel(StandardMaterial3D::TEXTURE_CHANNEL_GREEN);
  					if (!mr.has("metallicFactor")) {
  						material->set_metallic(1);
  					}
  					if (!mr.has("roughnessFactor")) {
  						material->set_roughness(1);
  					}
  				}
  			}
  		}
  
  		if (d.has("normalTexture")) {
  			const Dictionary &bct = d["normalTexture"];
  			if (bct.has("index")) {
  				material->set_texture(StandardMaterial3D::TEXTURE_NORMAL, _get_texture(state, bct["index"]));
  				material->set_feature(StandardMaterial3D::FEATURE_NORMAL_MAPPING, true);
  			}
  			if (bct.has("scale")) {
  				material->set_normal_scale(bct["scale"]);
  			}
  		}
  		if (d.has("occlusionTexture")) {
  			const Dictionary &bct = d["occlusionTexture"];
  			if (bct.has("index")) {
  				material->set_texture(StandardMaterial3D::TEXTURE_AMBIENT_OCCLUSION, _get_texture(state, bct["index"]));
  				material->set_ao_texture_channel(StandardMaterial3D::TEXTURE_CHANNEL_RED);
  				material->set_feature(StandardMaterial3D::FEATURE_AMBIENT_OCCLUSION, true);
  			}
  		}
  
  		if (d.has("emissiveFactor")) {
  			const Array &arr = d["emissiveFactor"];
  			ERR_FAIL_COND_V(arr.size() != 3, ERR_PARSE_ERROR);
  			const Color c = Color(arr[0], arr[1], arr[2]).to_srgb();
  			material->set_feature(StandardMaterial3D::FEATURE_EMISSION, true);
  
  			material->set_emission(c);
  		}
  
  		if (d.has("emissiveTexture")) {
  			const Dictionary &bct = d["emissiveTexture"];
  			if (bct.has("index")) {
  				material->set_texture(StandardMaterial3D::TEXTURE_EMISSION, _get_texture(state, bct["index"]));
  				material->set_feature(StandardMaterial3D::FEATURE_EMISSION, true);
  				material->set_emission(Color(0, 0, 0));
  			}
  		}
  
  		if (d.has("doubleSided")) {
  			const bool ds = d["doubleSided"];
  			if (ds) {
  				material->set_cull_mode(StandardMaterial3D::CULL_DISABLED);
  			}
  		}
  
  		if (d.has("alphaMode")) {
  			const String &am = d["alphaMode"];
  			if (am == "BLEND") {
  				material->set_transparency(StandardMaterial3D::TRANSPARENCY_ALPHA_DEPTH_PRE_PASS);
  			} else if (am == "MASK") {
  				material->set_transparency(StandardMaterial3D::TRANSPARENCY_ALPHA_SCISSOR);
  				if (d.has("alphaCutoff")) {
  					material->set_alpha_scissor_threshold(d["alphaCutoff"]);
  				} else {
  					material->set_alpha_scissor_threshold(0.5f);
  				}
  			}
  		}
  
  		state.materials.push_back(material);
  	}
  
  	print_verbose("Total materials: " + itos(state.materials.size()));
  
  	return OK;
  }
  
  EditorSceneImporterGLTF::GLTFNodeIndex EditorSceneImporterGLTF::_find_highest_node(GLTFState &state, const Vector<GLTFNodeIndex> &subset) {
  	int highest = -1;
  	GLTFNodeIndex best_node = -1;
  
  	for (int i = 0; i < subset.size(); ++i) {
  		const GLTFNodeIndex node_i = subset[i];
  		const GLTFNode *node = state.nodes[node_i];
  
  		if (highest == -1 || node->height < highest) {
  			highest = node->height;
  			best_node = node_i;
  		}
  	}
  
  	return best_node;
  }
  
  bool EditorSceneImporterGLTF::_capture_nodes_in_skin(GLTFState &state, GLTFSkin &skin, const GLTFNodeIndex node_index) {
  	bool found_joint = false;
  
  	for (int i = 0; i < state.nodes[node_index]->children.size(); ++i) {
  		found_joint |= _capture_nodes_in_skin(state, skin, state.nodes[node_index]->children[i]);
  	}
  
  	if (found_joint) {
  		// Mark it if we happen to find another skins joint...
  		if (state.nodes[node_index]->joint && skin.joints.find(node_index) < 0) {
  			skin.joints.push_back(node_index);
  		} else if (skin.non_joints.find(node_index) < 0) {
  			skin.non_joints.push_back(node_index);
  		}
  	}
  
  	if (skin.joints.find(node_index) > 0) {
  		return true;
  	}
  
  	return false;
  }
  
  void EditorSceneImporterGLTF::_capture_nodes_for_multirooted_skin(GLTFState &state, GLTFSkin &skin) {
  	DisjointSet<GLTFNodeIndex> disjoint_set;
  
  	for (int i = 0; i < skin.joints.size(); ++i) {
  		const GLTFNodeIndex node_index = skin.joints[i];
  		const GLTFNodeIndex parent = state.nodes[node_index]->parent;
  		disjoint_set.insert(node_index);
  
  		if (skin.joints.find(parent) >= 0) {
  			disjoint_set.create_union(parent, node_index);
  		}
  	}
  
  	Vector<GLTFNodeIndex> roots;
  	disjoint_set.get_representatives(roots);
  
  	if (roots.size() <= 1) {
  		return;
  	}
  
  	int maxHeight = -1;
  
  	// Determine the max height rooted tree
  	for (int i = 0; i < roots.size(); ++i) {
  		const GLTFNodeIndex root = roots[i];
  
  		if (maxHeight == -1 || state.nodes[root]->height < maxHeight) {
  			maxHeight = state.nodes[root]->height;
  		}
  	}
  
  	// Go up the tree till all of the multiple roots of the skin are at the same hierarchy level.
  	// This sucks, but 99% of all game engines (not just Godot) would have this same issue.
  	for (int i = 0; i < roots.size(); ++i) {
  		GLTFNodeIndex current_node = roots[i];
  		while (state.nodes[current_node]->height > maxHeight) {
  			GLTFNodeIndex parent = state.nodes[current_node]->parent;
  
  			if (state.nodes[parent]->joint && skin.joints.find(parent) < 0) {
  				skin.joints.push_back(parent);
  			} else if (skin.non_joints.find(parent) < 0) {
  				skin.non_joints.push_back(parent);
  			}
  
  			current_node = parent;
  		}
  
  		// replace the roots
  		roots.write[i] = current_node;
  	}
  
  	// Climb up the tree until they all have the same parent
  	bool all_same;
  
  	do {
  		all_same = true;
  		const GLTFNodeIndex first_parent = state.nodes[roots[0]]->parent;
  
  		for (int i = 1; i < roots.size(); ++i) {
  			all_same &= (first_parent == state.nodes[roots[i]]->parent);
  		}
  
  		if (!all_same) {
  			for (int i = 0; i < roots.size(); ++i) {
  				const GLTFNodeIndex current_node = roots[i];
  				const GLTFNodeIndex parent = state.nodes[current_node]->parent;
  
  				if (state.nodes[parent]->joint && skin.joints.find(parent) < 0) {
  					skin.joints.push_back(parent);
  				} else if (skin.non_joints.find(parent) < 0) {
  					skin.non_joints.push_back(parent);
  				}
  
  				roots.write[i] = parent;
  			}
  		}
  
  	} while (!all_same);
  }
  
  Error EditorSceneImporterGLTF::_expand_skin(GLTFState &state, GLTFSkin &skin) {
  	_capture_nodes_for_multirooted_skin(state, skin);
  
  	// Grab all nodes that lay in between skin joints/nodes
  	DisjointSet<GLTFNodeIndex> disjoint_set;
  
  	Vector<GLTFNodeIndex> all_skin_nodes;
  	all_skin_nodes.append_array(skin.joints);
  	all_skin_nodes.append_array(skin.non_joints);
  
  	for (int i = 0; i < all_skin_nodes.size(); ++i) {
  		const GLTFNodeIndex node_index = all_skin_nodes[i];
  		const GLTFNodeIndex parent = state.nodes[node_index]->parent;
  		disjoint_set.insert(node_index);
  
  		if (all_skin_nodes.find(parent) >= 0) {
  			disjoint_set.create_union(parent, node_index);
  		}
  	}
  
  	Vector<GLTFNodeIndex> out_owners;
  	disjoint_set.get_representatives(out_owners);
  
  	Vector<GLTFNodeIndex> out_roots;
  
  	for (int i = 0; i < out_owners.size(); ++i) {
  		Vector<GLTFNodeIndex> set;
  		disjoint_set.get_members(set, out_owners[i]);
  
  		const GLTFNodeIndex root = _find_highest_node(state, set);
  		ERR_FAIL_COND_V(root < 0, FAILED);
  		out_roots.push_back(root);
  	}
  
  	out_roots.sort();
  
  	for (int i = 0; i < out_roots.size(); ++i) {
  		_capture_nodes_in_skin(state, skin, out_roots[i]);
  	}
  
  	skin.roots = out_roots;
  
  	return OK;
  }
  
  Error EditorSceneImporterGLTF::_verify_skin(GLTFState &state, GLTFSkin &skin) {
  	// This may seem duplicated from expand_skins, but this is really a sanity check! (so it kinda is)
  	// In case additional interpolating logic is added to the skins, this will help ensure that you
  	// do not cause it to self implode into a fiery blaze
  
  	// We are going to re-calculate the root nodes and compare them to the ones saved in the skin,
  	// then ensure the multiple trees (if they exist) are on the same sublevel
  
  	// Grab all nodes that lay in between skin joints/nodes
  	DisjointSet<GLTFNodeIndex> disjoint_set;
  
  	Vector<GLTFNodeIndex> all_skin_nodes;
  	all_skin_nodes.append_array(skin.joints);
  	all_skin_nodes.append_array(skin.non_joints);
  
  	for (int i = 0; i < all_skin_nodes.size(); ++i) {
  		const GLTFNodeIndex node_index = all_skin_nodes[i];
  		const GLTFNodeIndex parent = state.nodes[node_index]->parent;
  		disjoint_set.insert(node_index);
  
  		if (all_skin_nodes.find(parent) >= 0) {
  			disjoint_set.create_union(parent, node_index);
  		}
  	}
  
  	Vector<GLTFNodeIndex> out_owners;
  	disjoint_set.get_representatives(out_owners);
  
  	Vector<GLTFNodeIndex> out_roots;
  
  	for (int i = 0; i < out_owners.size(); ++i) {
  		Vector<GLTFNodeIndex> set;
  		disjoint_set.get_members(set, out_owners[i]);
  
  		const GLTFNodeIndex root = _find_highest_node(state, set);
  		ERR_FAIL_COND_V(root < 0, FAILED);
  		out_roots.push_back(root);
  	}
  
  	out_roots.sort();
  
  	ERR_FAIL_COND_V(out_roots.size() == 0, FAILED);
  
  	// Make sure the roots are the exact same (they better be)
  	ERR_FAIL_COND_V(out_roots.size() != skin.roots.size(), FAILED);
  	for (int i = 0; i < out_roots.size(); ++i) {
  		ERR_FAIL_COND_V(out_roots[i] != skin.roots[i], FAILED);
  	}
  
  	// Single rooted skin? Perfectly ok!
  	if (out_roots.size() == 1) {
  		return OK;
  	}
  
  	// Make sure all parents of a multi-rooted skin are the SAME
  	const GLTFNodeIndex parent = state.nodes[out_roots[0]]->parent;
  	for (int i = 1; i < out_roots.size(); ++i) {
  		if (state.nodes[out_roots[i]]->parent != parent) {
  			return FAILED;
  		}
  	}
  
  	return OK;
  }
  
  Error EditorSceneImporterGLTF::_parse_skins(GLTFState &state) {
  	if (!state.json.has("skins")) {
  		return OK;
  	}
  
  	const Array &skins = state.json["skins"];
  
  	// Create the base skins, and mark nodes that are joints
  	for (int i = 0; i < skins.size(); i++) {
  		const Dictionary &d = skins[i];
  
  		GLTFSkin skin;
  
  		ERR_FAIL_COND_V(!d.has("joints"), ERR_PARSE_ERROR);
  
  		const Array &joints = d["joints"];
  
  		if (d.has("inverseBindMatrices")) {
  			skin.inverse_binds = _decode_accessor_as_xform(state, d["inverseBindMatrices"], false);
  			ERR_FAIL_COND_V(skin.inverse_binds.size() != joints.size(), ERR_PARSE_ERROR);
  		}
  
  		for (int j = 0; j < joints.size(); j++) {
  			const GLTFNodeIndex node = joints[j];
  			ERR_FAIL_INDEX_V(node, state.nodes.size(), ERR_PARSE_ERROR);
  
  			skin.joints.push_back(node);
  			skin.joints_original.push_back(node);
  
  			state.nodes[node]->joint = true;
  		}
  
  		if (d.has("name")) {
  			skin.name = d["name"];
  		}
  
  		if (d.has("skeleton")) {
  			skin.skin_root = d["skeleton"];
  		}
  
  		state.skins.push_back(skin);
  	}
  
  	for (GLTFSkinIndex i = 0; i < state.skins.size(); ++i) {
  		GLTFSkin &skin = state.skins.write[i];
  
  		// Expand the skin to capture all the extra non-joints that lie in between the actual joints,
  		// and expand the hierarchy to ensure multi-rooted trees lie on the same height level
  		ERR_FAIL_COND_V(_expand_skin(state, skin), ERR_PARSE_ERROR);
  		ERR_FAIL_COND_V(_verify_skin(state, skin), ERR_PARSE_ERROR);
  	}
  
  	print_verbose("glTF: Total skins: " + itos(state.skins.size()));
  
  	return OK;
  }
  
  Error EditorSceneImporterGLTF::_determine_skeletons(GLTFState &state) {
  	// Using a disjoint set, we are going to potentially combine all skins that are actually branches
  	// of a main skeleton, or treat skins defining the same set of nodes as ONE skeleton.
  	// This is another unclear issue caused by the current glTF specification.
  
  	DisjointSet<GLTFNodeIndex> skeleton_sets;
  
  	for (GLTFSkinIndex skin_i = 0; skin_i < state.skins.size(); ++skin_i) {
  		const GLTFSkin &skin = state.skins[skin_i];
  
  		Vector<GLTFNodeIndex> all_skin_nodes;
  		all_skin_nodes.append_array(skin.joints);
  		all_skin_nodes.append_array(skin.non_joints);
  
  		for (int i = 0; i < all_skin_nodes.size(); ++i) {
  			const GLTFNodeIndex node_index = all_skin_nodes[i];
  			const GLTFNodeIndex parent = state.nodes[node_index]->parent;
  			skeleton_sets.insert(node_index);
  
  			if (all_skin_nodes.find(parent) >= 0) {
  				skeleton_sets.create_union(parent, node_index);
  			}
  		}
  
  		// We are going to connect the separate skin subtrees in each skin together
  		// so that the final roots are entire sets of valid skin trees
  		for (int i = 1; i < skin.roots.size(); ++i) {
  			skeleton_sets.create_union(skin.roots[0], skin.roots[i]);
  		}
  	}
  
  	{ // attempt to joint all touching subsets (siblings/parent are part of another skin)
  		Vector<GLTFNodeIndex> groups_representatives;
  		skeleton_sets.get_representatives(groups_representatives);
  
  		Vector<GLTFNodeIndex> highest_group_members;
  		Vector<Vector<GLTFNodeIndex>> groups;
  		for (int i = 0; i < groups_representatives.size(); ++i) {
  			Vector<GLTFNodeIndex> group;
  			skeleton_sets.get_members(group, groups_representatives[i]);
  			highest_group_members.push_back(_find_highest_node(state, group));
  			groups.push_back(group);
  		}
  
  		for (int i = 0; i < highest_group_members.size(); ++i) {
  			const GLTFNodeIndex node_i = highest_group_members[i];
  
  			// Attach any siblings together (this needs to be done n^2/2 times)
  			for (int j = i + 1; j < highest_group_members.size(); ++j) {
  				const GLTFNodeIndex node_j = highest_group_members[j];
  
  				// Even if they are siblings under the root! :)
  				if (state.nodes[node_i]->parent == state.nodes[node_j]->parent) {
  					skeleton_sets.create_union(node_i, node_j);
  				}
  			}
  
  			// Attach any parenting going on together (we need to do this n^2 times)
  			const GLTFNodeIndex node_i_parent = state.nodes[node_i]->parent;
  			if (node_i_parent >= 0) {
  				for (int j = 0; j < groups.size() && i != j; ++j) {
  					const Vector<GLTFNodeIndex> &group = groups[j];
  
  					if (group.find(node_i_parent) >= 0) {
  						const GLTFNodeIndex node_j = highest_group_members[j];
  						skeleton_sets.create_union(node_i, node_j);
  					}
  				}
  			}
  		}
  	}
  
  	// At this point, the skeleton groups should be finalized
  	Vector<GLTFNodeIndex> skeleton_owners;
  	skeleton_sets.get_representatives(skeleton_owners);
  
  	// Mark all the skins actual skeletons, after we have merged them
  	for (GLTFSkeletonIndex skel_i = 0; skel_i < skeleton_owners.size(); ++skel_i) {
  		const GLTFNodeIndex skeleton_owner = skeleton_owners[skel_i];
  		GLTFSkeleton skeleton;
  
  		Vector<GLTFNodeIndex> skeleton_nodes;
  		skeleton_sets.get_members(skeleton_nodes, skeleton_owner);
  
  		for (GLTFSkinIndex skin_i = 0; skin_i < state.skins.size(); ++skin_i) {
  			GLTFSkin &skin = state.skins.write[skin_i];
  
  			// If any of the the skeletons nodes exist in a skin, that skin now maps to the skeleton
  			for (int i = 0; i < skeleton_nodes.size(); ++i) {
  				GLTFNodeIndex skel_node_i = skeleton_nodes[i];
  				if (skin.joints.find(skel_node_i) >= 0 || skin.non_joints.find(skel_node_i) >= 0) {
  					skin.skeleton = skel_i;
  					continue;
  				}
  			}
  		}
  
  		Vector<GLTFNodeIndex> non_joints;
  		for (int i = 0; i < skeleton_nodes.size(); ++i) {
  			const GLTFNodeIndex node_i = skeleton_nodes[i];
  
  			if (state.nodes[node_i]->joint) {
  				skeleton.joints.push_back(node_i);
  			} else {
  				non_joints.push_back(node_i);
  			}
  		}
  
  		state.skeletons.push_back(skeleton);
  
  		_reparent_non_joint_skeleton_subtrees(state, state.skeletons.write[skel_i], non_joints);
  	}
  
  	for (GLTFSkeletonIndex skel_i = 0; skel_i < state.skeletons.size(); ++skel_i) {
  		GLTFSkeleton &skeleton = state.skeletons.write[skel_i];
  
  		for (int i = 0; i < skeleton.joints.size(); ++i) {
  			const GLTFNodeIndex node_i = skeleton.joints[i];
  			GLTFNode *node = state.nodes[node_i];
  
  			ERR_FAIL_COND_V(!node->joint, ERR_PARSE_ERROR);
  			ERR_FAIL_COND_V(node->skeleton >= 0, ERR_PARSE_ERROR);
  			node->skeleton = skel_i;
  		}
  
  		ERR_FAIL_COND_V(_determine_skeleton_roots(state, skel_i), ERR_PARSE_ERROR);
  	}
  
  	return OK;
  }
  
  Error EditorSceneImporterGLTF::_reparent_non_joint_skeleton_subtrees(GLTFState &state, GLTFSkeleton &skeleton, const Vector<GLTFNodeIndex> &non_joints) {
  	DisjointSet<GLTFNodeIndex> subtree_set;
  
  	// Populate the disjoint set with ONLY non joints that are in the skeleton hierarchy (non_joints vector)
  	// This way we can find any joints that lie in between joints, as the current glTF specification
  	// mentions nothing about non-joints being in between joints of the same skin. Hopefully one day we
  	// can remove this code.
  
  	// skinD depicted here explains this issue:
  	// http://github.com/KhronosGroup/glTF-Asset-Generator/blob/master/Output/Positive/Animation_Skin
  
  	for (int i = 0; i < non_joints.size(); ++i) {
  		const GLTFNodeIndex node_i = non_joints[i];
  
  		subtree_set.insert(node_i);
  
  		const GLTFNodeIndex parent_i = state.nodes[node_i]->parent;
  		if (parent_i >= 0 && non_joints.find(parent_i) >= 0 && !state.nodes[parent_i]->joint) {
  			subtree_set.create_union(parent_i, node_i);
  		}
  	}
  
  	// Find all the non joint subtrees and re-parent them to a new "fake" joint
  
  	Vector<GLTFNodeIndex> non_joint_subtree_roots;
  	subtree_set.get_representatives(non_joint_subtree_roots);
  
  	for (int root_i = 0; root_i < non_joint_subtree_roots.size(); ++root_i) {
  		const GLTFNodeIndex subtree_root = non_joint_subtree_roots[root_i];
  
  		Vector<GLTFNodeIndex> subtree_nodes;
  		subtree_set.get_members(subtree_nodes, subtree_root);
  
  		for (int subtree_i = 0; subtree_i < subtree_nodes.size(); ++subtree_i) {
  			ERR_FAIL_COND_V(_reparent_to_fake_joint(state, skeleton, subtree_nodes[subtree_i]), FAILED);
  
  			// We modified the tree, recompute all the heights
  			_compute_node_heights(state);
  		}
  	}
  
  	return OK;
  }
  
  Error EditorSceneImporterGLTF::_reparent_to_fake_joint(GLTFState &state, GLTFSkeleton &skeleton, const GLTFNodeIndex node_index) {
  	GLTFNode *node = state.nodes[node_index];
  
  	// Can we just "steal" this joint if it is just a spatial node?
  	if (node->skin < 0 && node->mesh < 0 && node->camera < 0) {
  		node->joint = true;
  		// Add the joint to the skeletons joints
  		skeleton.joints.push_back(node_index);
  		return OK;
  	}
  
  	GLTFNode *fake_joint = memnew(GLTFNode);
  	const GLTFNodeIndex fake_joint_index = state.nodes.size();
  	state.nodes.push_back(fake_joint);
  
  	// We better not be a joint, or we messed up in our logic
  	if (node->joint) {
  		return FAILED;
  	}
  
  	fake_joint->translation = node->translation;
  	fake_joint->rotation = node->rotation;
  	fake_joint->scale = node->scale;
  	fake_joint->xform = node->xform;
  	fake_joint->joint = true;
  
  	// We can use the exact same name here, because the joint will be inside a skeleton and not the scene
  	fake_joint->name = node->name;
  
  	// Clear the nodes transforms, since it will be parented to the fake joint
  	node->translation = Vector3(0, 0, 0);
  	node->rotation = Quat();
  	node->scale = Vector3(1, 1, 1);
  	node->xform = Transform();
  
  	// Transfer the node children to the fake joint
  	for (int child_i = 0; child_i < node->children.size(); ++child_i) {
  		GLTFNode *child = state.nodes[node->children[child_i]];
  		child->parent = fake_joint_index;
  	}
  
  	fake_joint->children = node->children;
  	node->children.clear();
  
  	// add the fake joint to the parent and remove the original joint
  	if (node->parent >= 0) {
  		GLTFNode *parent = state.nodes[node->parent];
  		parent->children.erase(node_index);
  		parent->children.push_back(fake_joint_index);
  		fake_joint->parent = node->parent;
  	}
  
  	// Add the node to the fake joint
  	fake_joint->children.push_back(node_index);
  	node->parent = fake_joint_index;
  	node->fake_joint_parent = fake_joint_index;
  
  	// Add the fake joint to the skeletons joints
  	skeleton.joints.push_back(fake_joint_index);
  
  	// Replace skin_skeletons with fake joints if we must.
  	for (GLTFSkinIndex skin_i = 0; skin_i < state.skins.size(); ++skin_i) {
  		GLTFSkin &skin = state.skins.write[skin_i];
  		if (skin.skin_root == node_index) {
  			skin.skin_root = fake_joint_index;
  		}
  	}
  
  	return OK;
  }
  
  Error EditorSceneImporterGLTF::_determine_skeleton_roots(GLTFState &state, const GLTFSkeletonIndex skel_i) {
  	DisjointSet<GLTFNodeIndex> disjoint_set;
  
  	for (GLTFNodeIndex i = 0; i < state.nodes.size(); ++i) {
  		const GLTFNode *node = state.nodes[i];
  
  		if (node->skeleton != skel_i) {
  			continue;
  		}
  
  		disjoint_set.insert(i);
  
  		if (node->parent >= 0 && state.nodes[node->parent]->skeleton == skel_i) {
  			disjoint_set.create_union(node->parent, i);
  		}
  	}
  
  	GLTFSkeleton &skeleton = state.skeletons.write[skel_i];
  
  	Vector<GLTFNodeIndex> owners;
  	disjoint_set.get_representatives(owners);
  
  	Vector<GLTFNodeIndex> roots;
  
  	for (int i = 0; i < owners.size(); ++i) {
  		Vector<GLTFNodeIndex> set;
  		disjoint_set.get_members(set, owners[i]);
  		const GLTFNodeIndex root = _find_highest_node(state, set);
  		ERR_FAIL_COND_V(root < 0, FAILED);
  		roots.push_back(root);
  	}
  
  	roots.sort();
  
  	skeleton.roots = roots;
  
  	if (roots.size() == 0) {
  		return FAILED;
  	} else if (roots.size() == 1) {
  		return OK;
  	}
  
  	// Check that the subtrees have the same parent root
  	const GLTFNodeIndex parent = state.nodes[roots[0]]->parent;
  	for (int i = 1; i < roots.size(); ++i) {
  		if (state.nodes[roots[i]]->parent != parent) {
  			return FAILED;
  		}
  	}
  
  	return OK;
  }
  
  Error EditorSceneImporterGLTF::_create_skeletons(GLTFState &state) {
  	for (GLTFSkeletonIndex skel_i = 0; skel_i < state.skeletons.size(); ++skel_i) {
  		GLTFSkeleton &gltf_skeleton = state.skeletons.write[skel_i];
  
  		Skeleton3D *skeleton = memnew(Skeleton3D);
  		gltf_skeleton.godot_skeleton = skeleton;
  
  		// Make a unique name, no gltf node represents this skeleton
  		skeleton->set_name(_gen_unique_name(state, "Skeleton"));
  
  		List<GLTFNodeIndex> bones;
  
  		for (int i = 0; i < gltf_skeleton.roots.size(); ++i) {
  			bones.push_back(gltf_skeleton.roots[i]);
  		}
  
  		// Make the skeleton creation deterministic by going through the roots in
  		// a sorted order, and DEPTH FIRST
  		bones.sort();
  
  		while (!bones.empty()) {
  			const GLTFNodeIndex node_i = bones.front()->get();
  			bones.pop_front();
  
  			GLTFNode *node = state.nodes[node_i];
  			ERR_FAIL_COND_V(node->skeleton != skel_i, FAILED);
  
  			{ // Add all child nodes to the stack (deterministically)
  				Vector<GLTFNodeIndex> child_nodes;
  				for (int i = 0; i < node->children.size(); ++i) {
  					const GLTFNodeIndex child_i = node->children[i];
  					if (state.nodes[child_i]->skeleton == skel_i) {
  						child_nodes.push_back(child_i);
  					}
  				}
  
  				// Depth first insertion
  				child_nodes.sort();
  				for (int i = child_nodes.size() - 1; i >= 0; --i) {
  					bones.push_front(child_nodes[i]);
  				}
  			}
  
  			const int bone_index = skeleton->get_bone_count();
  
  			if (node->name.empty()) {
  				node->name = "bone";
  			}
  
  			node->name = _gen_unique_bone_name(state, skel_i, node->name);
  
  			skeleton->add_bone(node->name);
  			skeleton->set_bone_rest(bone_index, node->xform);
  
  			if (node->parent >= 0 && state.nodes[node->parent]->skeleton == skel_i) {
  				const int bone_parent = skeleton->find_bone(state.nodes[node->parent]->name);
  				ERR_FAIL_COND_V(bone_parent < 0, FAILED);
  				skeleton->set_bone_parent(bone_index, skeleton->find_bone(state.nodes[node->parent]->name));
  			}
  
  			state.scene_nodes.insert(node_i, skeleton);
  		}
  	}
  
  	ERR_FAIL_COND_V(_map_skin_joints_indices_to_skeleton_bone_indices(state), ERR_PARSE_ERROR);
  
  	return OK;
  }
  
  Error EditorSceneImporterGLTF::_map_skin_joints_indices_to_skeleton_bone_indices(GLTFState &state) {
  	for (GLTFSkinIndex skin_i = 0; skin_i < state.skins.size(); ++skin_i) {
  		GLTFSkin &skin = state.skins.write[skin_i];
  
  		const GLTFSkeleton &skeleton = state.skeletons[skin.skeleton];
  
  		for (int joint_index = 0; joint_index < skin.joints_original.size(); ++joint_index) {
  			const GLTFNodeIndex node_i = skin.joints_original[joint_index];
  			const GLTFNode *node = state.nodes[node_i];
  
  			skin.joint_i_to_name.insert(joint_index, node->name);
  
  			const int bone_index = skeleton.godot_skeleton->find_bone(node->name);
  			ERR_FAIL_COND_V(bone_index < 0, FAILED);
  
  			skin.joint_i_to_bone_i.insert(joint_index, bone_index);
  		}
  	}
  
  	return OK;
  }
  
  Error EditorSceneImporterGLTF::_create_skins(GLTFState &state) {
  	for (GLTFSkinIndex skin_i = 0; skin_i < state.skins.size(); ++skin_i) {
  		GLTFSkin &gltf_skin = state.skins.write[skin_i];
  
  		Ref<Skin> skin;
  		skin.instance();
  
  		// Some skins don't have IBM's! What absolute monsters!
  		const bool has_ibms = !gltf_skin.inverse_binds.empty();
  
  		for (int joint_i = 0; joint_i < gltf_skin.joints_original.size(); ++joint_i) {
  			Transform xform;
  			if (has_ibms) {
  				xform = gltf_skin.inverse_binds[joint_i];
  			}
  
  			if (state.use_named_skin_binds) {
  				StringName name = gltf_skin.joint_i_to_name[joint_i];
  				skin->add_named_bind(name, xform);
  			} else {
  				int bone_i = gltf_skin.joint_i_to_bone_i[joint_i];
  				skin->add_bind(bone_i, xform);
  			}
  		}
  
  		gltf_skin.godot_skin = skin;
  	}
  
  	// Purge the duplicates!
  	_remove_duplicate_skins(state);
  
  	// Create unique names now, after removing duplicates
  	for (GLTFSkinIndex skin_i = 0; skin_i < state.skins.size(); ++skin_i) {
  		Ref<Skin> skin = state.skins[skin_i].godot_skin;
  		if (skin->get_name().empty()) {
  			// Make a unique name, no gltf node represents this skin
  			skin->set_name(_gen_unique_name(state, "Skin"));
  		}
  	}
  
  	return OK;
  }
  
  bool EditorSceneImporterGLTF::_skins_are_same(const Ref<Skin> &skin_a, const Ref<Skin> &skin_b) {
  	if (skin_a->get_bind_count() != skin_b->get_bind_count()) {
  		return false;
  	}
  
  	for (int i = 0; i < skin_a->get_bind_count(); ++i) {
  		if (skin_a->get_bind_bone(i) != skin_b->get_bind_bone(i)) {
  			return false;
  		}
  
  		Transform a_xform = skin_a->get_bind_pose(i);
  		Transform b_xform = skin_b->get_bind_pose(i);
  
  		if (a_xform != b_xform) {
  			return false;
  		}
  	}
  
  	return true;
  }
  
  void EditorSceneImporterGLTF::_remove_duplicate_skins(GLTFState &state) {
  	for (int i = 0; i < state.skins.size(); ++i) {
  		for (int j = i + 1; j < state.skins.size(); ++j) {
  			const Ref<Skin> &skin_i = state.skins[i].godot_skin;
  			const Ref<Skin> &skin_j = state.skins[j].godot_skin;
  
  			if (_skins_are_same(skin_i, skin_j)) {
  				// replace it and delete the old
  				state.skins.write[j].godot_skin = skin_i;
  			}
  		}
  	}
  }
  
  Error EditorSceneImporterGLTF::_parse_lights(GLTFState &state) {
  	if (!state.json.has("extensions")) {
  		return OK;
  	}
  	Dictionary extensions = state.json["extensions"];
  	if (!extensions.has("KHR_lights_punctual")) {
  		return OK;
  	}
  	Dictionary lights_punctual = extensions["KHR_lights_punctual"];
  	if (!lights_punctual.has("lights")) {
  		return OK;
  	}
  
  	const Array &lights = lights_punctual["lights"];
  
  	for (GLTFLightIndex light_i = 0; light_i < lights.size(); light_i++) {
  		const Dictionary &d = lights[light_i];
  
  		GLTFLight light;
  		ERR_FAIL_COND_V(!d.has("type"), ERR_PARSE_ERROR);
  		const String &type = d["type"];
  		light.type = type;
  
  		if (d.has("color")) {
  			const Array &arr = d["color"];
  			ERR_FAIL_COND_V(arr.size() != 3, ERR_PARSE_ERROR);
  			const Color c = Color(arr[0], arr[1], arr[2]).to_srgb();
  			light.color = c;
  		}
  		if (d.has("intensity")) {
  			light.intensity = d["intensity"];
  		}
  		if (d.has("range")) {
  			light.range = d["range"];
  		}
  		if (type == "spot") {
  			const Dictionary &spot = d["spot"];
  			light.inner_cone_angle = spot["innerConeAngle"];
  			light.outer_cone_angle = spot["outerConeAngle"];
  			ERR_FAIL_COND_V_MSG(light.inner_cone_angle >= light.outer_cone_angle, ERR_PARSE_ERROR, "The inner angle must be smaller than the outer angle.");
  		} else if (type != "point" && type != "directional") {
  			ERR_FAIL_V_MSG(ERR_PARSE_ERROR, "Light type is unknown.");
  		}
  
  		state.lights.push_back(light);
  	}
  
  	print_verbose("glTF: Total lights: " + itos(state.lights.size()));
  
  	return OK;
  }
  
  Error EditorSceneImporterGLTF::_parse_cameras(GLTFState &state) {
  	if (!state.json.has("cameras")) {
  		return OK;
  	}
  
  	const Array &cameras = state.json["cameras"];
  
  	for (GLTFCameraIndex i = 0; i < cameras.size(); i++) {
  		const Dictionary &d = cameras[i];
  
  		GLTFCamera camera;
  		ERR_FAIL_COND_V(!d.has("type"), ERR_PARSE_ERROR);
  		const String &type = d["type"];
  		if (type == "orthographic") {
  			camera.perspective = false;
  			if (d.has("orthographic")) {
  				const Dictionary &og = d["orthographic"];
  				camera.fov_size = og["ymag"];
  				camera.zfar = og["zfar"];
  				camera.znear = og["znear"];
  			} else {
  				camera.fov_size = 10;
  			}
  
  		} else if (type == "perspective") {
  			camera.perspective = true;
  			if (d.has("perspective")) {
  				const Dictionary &ppt = d["perspective"];
  				// GLTF spec is in radians, Godot's camera is in degrees.
  				camera.fov_size = (double)ppt["yfov"] * 180.0 / Math_PI;
  				camera.zfar = ppt["zfar"];
  				camera.znear = ppt["znear"];
  			} else {
  				camera.fov_size = 10;
  			}
  		} else {
  			ERR_FAIL_V_MSG(ERR_PARSE_ERROR, "Camera should be in 'orthographic' or 'perspective'");
  		}
  
  		state.cameras.push_back(camera);
  	}
  
  	print_verbose("glTF: Total cameras: " + itos(state.cameras.size()));
  
  	return OK;
  }
  
  Error EditorSceneImporterGLTF::_parse_animations(GLTFState &state) {
  	if (!state.json.has("animations")) {
  		return OK;
  	}
  
  	const Array &animations = state.json["animations"];
  
  	for (GLTFAnimationIndex i = 0; i < animations.size(); i++) {
  		const Dictionary &d = animations[i];
  
  		GLTFAnimation animation;
  
  		if (!d.has("channels") || !d.has("samplers")) {
  			continue;
  		}
  
  		Array channels = d["channels"];
  		Array samplers = d["samplers"];
  
  		if (d.has("name")) {
  			String name = d["name"];
  			if (name.begins_with("loop") || name.ends_with("loop") || name.begins_with("cycle") || name.ends_with("cycle")) {
  				animation.loop = true;
  			}
  			animation.name = _sanitize_scene_name(name);
  		}
  
  		for (int j = 0; j < channels.size(); j++) {
  			const Dictionary &c = channels[j];
  			if (!c.has("target")) {
  				continue;
  			}
  
  			const Dictionary &t = c["target"];
  			if (!t.has("node") || !t.has("path")) {
  				continue;
  			}
  
  			ERR_FAIL_COND_V(!c.has("sampler"), ERR_PARSE_ERROR);
  			const int sampler = c["sampler"];
  			ERR_FAIL_INDEX_V(sampler, samplers.size(), ERR_PARSE_ERROR);
  
  			GLTFNodeIndex node = t["node"];
  			String path = t["path"];
  
  			ERR_FAIL_INDEX_V(node, state.nodes.size(), ERR_PARSE_ERROR);
  
  			GLTFAnimation::Track *track = nullptr;
  
  			if (!animation.tracks.has(node)) {
  				animation.tracks[node] = GLTFAnimation::Track();
  			}
  
  			track = &animation.tracks[node];
  
  			const Dictionary &s = samplers[sampler];
  
  			ERR_FAIL_COND_V(!s.has("input"), ERR_PARSE_ERROR);
  			ERR_FAIL_COND_V(!s.has("output"), ERR_PARSE_ERROR);
  
  			const int input = s["input"];
  			const int output = s["output"];
  
  			GLTFAnimation::Interpolation interp = GLTFAnimation::INTERP_LINEAR;
  			int output_count = 1;
  			if (s.has("interpolation")) {
  				const String &in = s["interpolation"];
  				if (in == "STEP") {
  					interp = GLTFAnimation::INTERP_STEP;
  				} else if (in == "LINEAR") {
  					interp = GLTFAnimation::INTERP_LINEAR;
  				} else if (in == "CATMULLROMSPLINE") {
  					interp = GLTFAnimation::INTERP_CATMULLROMSPLINE;
  					output_count = 3;
  				} else if (in == "CUBICSPLINE") {
  					interp = GLTFAnimation::INTERP_CUBIC_SPLINE;
  					output_count = 3;
  				}
  			}
  
  			const Vector<float> times = _decode_accessor_as_floats(state, input, false);
  			if (path == "translation") {
  				const Vector<Vector3> translations = _decode_accessor_as_vec3(state, output, false);
  				track->translation_track.interpolation = interp;
  				track->translation_track.times = Variant(times); //convert via variant
  				track->translation_track.values = Variant(translations); //convert via variant
  			} else if (path == "rotation") {
  				const Vector<Quat> rotations = _decode_accessor_as_quat(state, output, false);
  				track->rotation_track.interpolation = interp;
  				track->rotation_track.times = Variant(times); //convert via variant
  				track->rotation_track.values = rotations; //convert via variant
  			} else if (path == "scale") {
  				const Vector<Vector3> scales = _decode_accessor_as_vec3(state, output, false);
  				track->scale_track.interpolation = interp;
  				track->scale_track.times = Variant(times); //convert via variant
  				track->scale_track.values = Variant(scales); //convert via variant
  			} else if (path == "weights") {
  				const Vector<float> weights = _decode_accessor_as_floats(state, output, false);
  
  				ERR_FAIL_INDEX_V(state.nodes[node]->mesh, state.meshes.size(), ERR_PARSE_ERROR);
  				const GLTFMesh *mesh = &state.meshes[state.nodes[node]->mesh];
  				ERR_FAIL_COND_V(mesh->blend_weights.size() == 0, ERR_PARSE_ERROR);
  				const int wc = mesh->blend_weights.size();
  
  				track->weight_tracks.resize(wc);
  
  				const int expected_value_count = times.size() * output_count * wc;
  				ERR_FAIL_COND_V_MSG(weights.size() != expected_value_count, ERR_PARSE_ERROR, "Invalid weight data, expected " + itos(expected_value_count) + " weight values, got " + itos(weights.size()) + " instead.");
  
  				const int wlen = weights.size() / wc;
  				const float *r = weights.ptr();
  				for (int k = 0; k < wc; k++) { //separate tracks, having them together is not such a good idea
  					GLTFAnimation::Channel<float> cf;
  					cf.interpolation = interp;
  					cf.times = Variant(times);
  					Vector<float> wdata;
  					wdata.resize(wlen);
  					for (int l = 0; l < wlen; l++) {
  						wdata.write[l] = r[l * wc + k];
  					}
  
  					cf.values = wdata;
  					track->weight_tracks.write[k] = cf;
  				}
  			} else {
  				WARN_PRINT("Invalid path '" + path + "'.");
  			}
  		}
  
  		state.animations.push_back(animation);
  	}
  
  	print_verbose("glTF: Total animations '" + itos(state.animations.size()) + "'.");
  
  	return OK;
  }
  
  void EditorSceneImporterGLTF::_assign_scene_names(GLTFState &state) {
  	for (int i = 0; i < state.nodes.size(); i++) {
  		GLTFNode *n = state.nodes[i];
  
  		// Any joints get unique names generated when the skeleton is made, unique to the skeleton
  		if (n->skeleton >= 0) {
  			continue;
  		}
  
  		if (n->name.empty()) {
  			if (n->mesh >= 0) {
  				n->name = "Mesh";
  			} else if (n->camera >= 0) {
  				n->name = "Camera";
  			} else {
  				n->name = "Node";
  			}
  		}
  
  		n->name = _gen_unique_name(state, n->name);
  	}
  }
  
  BoneAttachment3D *EditorSceneImporterGLTF::_generate_bone_attachment(GLTFState &state, Skeleton3D *skeleton, const GLTFNodeIndex node_index) {
  	const GLTFNode *gltf_node = state.nodes[node_index];
  	const GLTFNode *bone_node = state.nodes[gltf_node->parent];
  
  	BoneAttachment3D *bone_attachment = memnew(BoneAttachment3D);
  	print_verbose("glTF: Creating bone attachment for: " + gltf_node->name);
  
  	ERR_FAIL_COND_V(!bone_node->joint, nullptr);
  
  	bone_attachment->set_bone_name(bone_node->name);
  
  	return bone_attachment;
  }
  
  MeshInstance3D *EditorSceneImporterGLTF::_generate_mesh_instance(GLTFState &state, Node *scene_parent, const GLTFNodeIndex node_index) {
  	const GLTFNode *gltf_node = state.nodes[node_index];
  
  	ERR_FAIL_INDEX_V(gltf_node->mesh, state.meshes.size(), nullptr);
  
  	MeshInstance3D *mi = memnew(MeshInstance3D);
  	print_verbose("glTF: Creating mesh for: " + gltf_node->name);
  
  	GLTFMesh &mesh = state.meshes.write[gltf_node->mesh];
  	mi->set_mesh(mesh.mesh);
  
  	if (mesh.mesh->get_name() == "") {
  		mesh.mesh->set_name(gltf_node->name);
  	}
  
  	for (int i = 0; i < mesh.blend_weights.size(); i++) {
  		mi->set("blend_shapes/" + mesh.mesh->get_blend_shape_name(i), mesh.blend_weights[i]);
  	}
  
  	return mi;
  }
  
  Light3D *EditorSceneImporterGLTF::_generate_light(GLTFState &state, Node *scene_parent, const GLTFNodeIndex node_index) {
  	const GLTFNode *gltf_node = state.nodes[node_index];
  
  	ERR_FAIL_INDEX_V(gltf_node->light, state.lights.size(), nullptr);
  
  	print_verbose("glTF: Creating light for: " + gltf_node->name);
  
  	const GLTFLight &l = state.lights[gltf_node->light];
  
  	float intensity = l.intensity;
  	if (intensity > 10) {
  		// GLTF spec has the default around 1, but Blender defaults lights to 100.
  		// The only sane way to handle this is to check where it came from and
  		// handle it accordingly. If it's over 10, it probably came from Blender.
  		intensity /= 100;
  	}
  
  	if (l.type == "directional") {
  		DirectionalLight3D *light = memnew(DirectionalLight3D);
  		light->set_param(Light3D::PARAM_ENERGY, intensity);
  		light->set_color(l.color);
  		return light;
  	}
  
  	const float range = CLAMP(l.range, 0, 4096);
  	// Doubling the range will double the effective brightness, so we need double attenuation (half brightness).
  	// We want to have double intensity give double brightness, so we need half the attenuation.
  	const float attenuation = range / intensity;
  	if (l.type == "point") {
  		OmniLight3D *light = memnew(OmniLight3D);
  		light->set_param(OmniLight3D::PARAM_ATTENUATION, attenuation);
  		light->set_param(OmniLight3D::PARAM_RANGE, range);
  		light->set_color(l.color);
  		return light;
  	}
  	if (l.type == "spot") {
  		SpotLight3D *light = memnew(SpotLight3D);
  		light->set_param(SpotLight3D::PARAM_ATTENUATION, attenuation);
  		light->set_param(SpotLight3D::PARAM_RANGE, range);
  		light->set_param(SpotLight3D::PARAM_SPOT_ANGLE, Math::rad2deg(l.outer_cone_angle));
  		light->set_color(l.color);
  
  		// Line of best fit derived from guessing, see http://www.desmos.com/calculator/biiflubp8b
  		// The points in desmos are not exact, except for (1, infinity).
  		float angle_ratio = l.inner_cone_angle / l.outer_cone_angle;
  		float angle_attenuation = 0.2 / (1 - angle_ratio) - 0.1;
  		light->set_param(SpotLight3D::PARAM_SPOT_ATTENUATION, angle_attenuation);
  		return light;
  	}
  	return nullptr;
  }
  
  Camera3D *EditorSceneImporterGLTF::_generate_camera(GLTFState &state, Node *scene_parent, const GLTFNodeIndex node_index) {
  	const GLTFNode *gltf_node = state.nodes[node_index];
  
  	ERR_FAIL_INDEX_V(gltf_node->camera, state.cameras.size(), nullptr);
  
  	Camera3D *camera = memnew(Camera3D);
  	print_verbose("glTF: Creating camera for: " + gltf_node->name);
  
  	const GLTFCamera &c = state.cameras[gltf_node->camera];
  	if (c.perspective) {
  		camera->set_perspective(c.fov_size, c.znear, c.zfar);
  	} else {
  		camera->set_orthogonal(c.fov_size, c.znear, c.zfar);
  	}
  
  	return camera;
  }
  
  Node3D *EditorSceneImporterGLTF::_generate_spatial(GLTFState &state, Node *scene_parent, const GLTFNodeIndex node_index) {
  	const GLTFNode *gltf_node = state.nodes[node_index];
  
  	Node3D *spatial = memnew(Node3D);
  	print_verbose("glTF: Creating spatial for: " + gltf_node->name);
  
  	return spatial;
  }
  
  void EditorSceneImporterGLTF::_generate_scene_node(GLTFState &state, Node *scene_parent, Node3D *scene_root, const GLTFNodeIndex node_index) {
  	const GLTFNode *gltf_node = state.nodes[node_index];
  
  	Node3D *current_node = nullptr;
  
  	// Is our parent a skeleton
  	Skeleton3D *active_skeleton = Object::cast_to<Skeleton3D>(scene_parent);
  
  	if (gltf_node->skeleton >= 0) {
  		Skeleton3D *skeleton = state.skeletons[gltf_node->skeleton].godot_skeleton;
  
  		if (active_skeleton != skeleton) {
  			ERR_FAIL_COND_MSG(active_skeleton != nullptr, "glTF: Generating scene detected direct parented Skeletons");
  
  			// Add it to the scene if it has not already been added
  			if (skeleton->get_parent() == nullptr) {
  				scene_parent->add_child(skeleton);
  				skeleton->set_owner(scene_root);
  			}
  		}
  
  		active_skeleton = skeleton;
  		current_node = skeleton;
  	}
  
  	// If we have an active skeleton, and the node is node skinned, we need to create a bone attachment
  	if (current_node == nullptr && active_skeleton != nullptr && gltf_node->skin < 0) {
  		BoneAttachment3D *bone_attachment = _generate_bone_attachment(state, active_skeleton, node_index);
  
  		scene_parent->add_child(bone_attachment);
  		bone_attachment->set_owner(scene_root);
  
  		// There is no gltf_node that represent this, so just directly create a unique name
  		bone_attachment->set_name(_gen_unique_name(state, "BoneAttachment"));
  
  		// We change the scene_parent to our bone attachment now. We do not set current_node because we want to make the node
  		// and attach it to the bone_attachment
  		scene_parent = bone_attachment;
  	}
  
  	// We still have not managed to make a node
  	if (current_node == nullptr) {
  		if (gltf_node->mesh >= 0) {
  			current_node = _generate_mesh_instance(state, scene_parent, node_index);
  		} else if (gltf_node->camera >= 0) {
  			current_node = _generate_camera(state, scene_parent, node_index);
  		} else if (gltf_node->light >= 0) {
  			current_node = _generate_light(state, scene_parent, node_index);
  		} else {
  			current_node = _generate_spatial(state, scene_parent, node_index);
  		}
  
  		scene_parent->add_child(current_node);
  		current_node->set_owner(scene_root);
  		current_node->set_transform(gltf_node->xform);
  		current_node->set_name(gltf_node->name);
  	}
  
  	state.scene_nodes.insert(node_index, current_node);
  
  	for (int i = 0; i < gltf_node->children.size(); ++i) {
  		_generate_scene_node(state, current_node, scene_root, gltf_node->children[i]);
  	}
  }
  
  template <class T>
  struct EditorSceneImporterGLTFInterpolate {
  	T lerp(const T &a, const T &b, float c) const {
  		return a + (b - a) * c;
  	}
  
  	T catmull_rom(const T &p0, const T &p1, const T &p2, const T &p3, float t) {
  		const float t2 = t * t;
  		const float t3 = t2 * t;
  
  		return 0.5f * ((2.0f * p1) + (-p0 + p2) * t + (2.0f * p0 - 5.0f * p1 + 4.0f * p2 - p3) * t2 + (-p0 + 3.0f * p1 - 3.0f * p2 + p3) * t3);
  	}
  
  	T bezier(T start, T control_1, T control_2, T end, float t) {
  		/* Formula from Wikipedia article on Bezier curves. */
  		const real_t omt = (1.0 - t);
  		const real_t omt2 = omt * omt;
  		const real_t omt3 = omt2 * omt;
  		const real_t t2 = t * t;
  		const real_t t3 = t2 * t;
  
  		return start * omt3 + control_1 * omt2 * t * 3.0 + control_2 * omt * t2 * 3.0 + end * t3;
  	}
  };
  
  // thank you for existing, partial specialization
  template <>
  struct EditorSceneImporterGLTFInterpolate<Quat> {
  	Quat lerp(const Quat &a, const Quat &b, const float c) const {
  		ERR_FAIL_COND_V_MSG(!a.is_normalized(), Quat(), "The quaternion \"a\" must be normalized.");
  		ERR_FAIL_COND_V_MSG(!b.is_normalized(), Quat(), "The quaternion \"b\" must be normalized.");
  
  		return a.slerp(b, c).normalized();
  	}
  
  	Quat catmull_rom(const Quat &p0, const Quat &p1, const Quat &p2, const Quat &p3, const float c) {
  		ERR_FAIL_COND_V_MSG(!p1.is_normalized(), Quat(), "The quaternion \"p1\" must be normalized.");
  		ERR_FAIL_COND_V_MSG(!p2.is_normalized(), Quat(), "The quaternion \"p2\" must be normalized.");
  
  		return p1.slerp(p2, c).normalized();
  	}
  
  	Quat bezier(const Quat start, const Quat control_1, const Quat control_2, const Quat end, const float t) {
  		ERR_FAIL_COND_V_MSG(!start.is_normalized(), Quat(), "The start quaternion must be normalized.");
  		ERR_FAIL_COND_V_MSG(!end.is_normalized(), Quat(), "The end quaternion must be normalized.");
  
  		return start.slerp(end, t).normalized();
  	}
  };
  
  template <class T>
  T EditorSceneImporterGLTF::_interpolate_track(const Vector<float> &p_times, const Vector<T> &p_values, const float p_time, const GLTFAnimation::Interpolation p_interp) {
  	//could use binary search, worth it?
  	int idx = -1;
  	for (int i = 0; i < p_times.size(); i++) {
  		if (p_times[i] > p_time) {
  			break;
  		}
  		idx++;
  	}
  
  	EditorSceneImporterGLTFInterpolate<T> interp;
  
  	switch (p_interp) {
  		case GLTFAnimation::INTERP_LINEAR: {
  			if (idx == -1) {
  				return p_values[0];
  			} else if (idx >= p_times.size() - 1) {
  				return p_values[p_times.size() - 1];
  			}
  
  			const float c = (p_time - p_times[idx]) / (p_times[idx + 1] - p_times[idx]);
  
  			return interp.lerp(p_values[idx], p_values[idx + 1], c);
  
  		} break;
  		case GLTFAnimation::INTERP_STEP: {
  			if (idx == -1) {
  				return p_values[0];
  			} else if (idx >= p_times.size() - 1) {
  				return p_values[p_times.size() - 1];
  			}
  
  			return p_values[idx];
  
  		} break;
  		case GLTFAnimation::INTERP_CATMULLROMSPLINE: {
  			if (idx == -1) {
  				return p_values[1];
  			} else if (idx >= p_times.size() - 1) {
  				return p_values[1 + p_times.size() - 1];
  			}
  
  			const float c = (p_time - p_times[idx]) / (p_times[idx + 1] - p_times[idx]);
  
  			return interp.catmull_rom(p_values[idx - 1], p_values[idx], p_values[idx + 1], p_values[idx + 3], c);
  
  		} break;
  		case GLTFAnimation::INTERP_CUBIC_SPLINE: {
  			if (idx == -1) {
  				return p_values[1];
  			} else if (idx >= p_times.size() - 1) {
  				return p_values[(p_times.size() - 1) * 3 + 1];
  			}
  
  			const float c = (p_time - p_times[idx]) / (p_times[idx + 1] - p_times[idx]);
  
  			const T from = p_values[idx * 3 + 1];
  			const T c1 = from + p_values[idx * 3 + 2];
  			const T to = p_values[idx * 3 + 4];
  			const T c2 = to + p_values[idx * 3 + 3];
  
  			return interp.bezier(from, c1, c2, to, c);
  
  		} break;
  	}
  
  	ERR_FAIL_V(p_values[0]);
  }
  
  void EditorSceneImporterGLTF::_import_animation(GLTFState &state, AnimationPlayer *ap, const GLTFAnimationIndex index, const int bake_fps) {
  	const GLTFAnimation &anim = state.animations[index];
  
  	String name = anim.name;
  	if (name.empty()) {
  		// No node represent these, and they are not in the hierarchy, so just make a unique name
  		name = _gen_unique_name(state, "Animation");
  	}
  
  	Ref<Animation> animation;
  	animation.instance();
  	animation->set_name(name);
  
  	if (anim.loop) {
  		animation->set_loop(true);
  	}
  
  	float length = 0;
  
  	for (Map<int, GLTFAnimation::Track>::Element *E = anim.tracks.front(); E; E = E->next()) {
  		const GLTFAnimation::Track &track = E->get();
  		//need to find the path
  		NodePath node_path;
  
  		GLTFNodeIndex node_index = E->key();
  		if (state.nodes[node_index]->fake_joint_parent >= 0) {
  			// Should be same as parent
  			node_index = state.nodes[node_index]->fake_joint_parent;
  		}
  
  		const GLTFNode *node = state.nodes[E->key()];
  
  		if (node->skeleton >= 0) {
  			const Skeleton3D *sk = Object::cast_to<Skeleton3D>(state.scene_nodes.find(node_index)->get());
  			ERR_FAIL_COND(sk == nullptr);
  
  			const String path = ap->get_parent()->get_path_to(sk);
  			const String bone = node->name;
  			node_path = path + ":" + bone;
  		} else {
  			node_path = ap->get_parent()->get_path_to(state.scene_nodes.find(node_index)->get());
  		}
  
  		for (int i = 0; i < track.rotation_track.times.size(); i++) {
  			length = MAX(length, track.rotation_track.times[i]);
  		}
  		for (int i = 0; i < track.translation_track.times.size(); i++) {
  			length = MAX(length, track.translation_track.times[i]);
  		}
  		for (int i = 0; i < track.scale_track.times.size(); i++) {
  			length = MAX(length, track.scale_track.times[i]);
  		}
  
  		for (int i = 0; i < track.weight_tracks.size(); i++) {
  			for (int j = 0; j < track.weight_tracks[i].times.size(); j++) {
  				length = MAX(length, track.weight_tracks[i].times[j]);
  			}
  		}
  
  		if (track.rotation_track.values.size() || track.translation_track.values.size() || track.scale_track.values.size()) {
  			//make transform track
  			int track_idx = animation->get_track_count();
  			animation->add_track(Animation::TYPE_TRANSFORM);
  			animation->track_set_path(track_idx, node_path);
  			animation->track_set_imported(track_idx, true);
  			//first determine animation length
  
  			const float increment = 1.0 / float(bake_fps);
  			float time = 0.0;
  
  			Vector3 base_pos;
  			Quat base_rot;
  			Vector3 base_scale = Vector3(1, 1, 1);
  
  			if (!track.rotation_track.values.size()) {
  				base_rot = state.nodes[E->key()]->rotation.normalized();
  			}
  
  			if (!track.translation_track.values.size()) {
  				base_pos = state.nodes[E->key()]->translation;
  			}
  
  			if (!track.scale_track.values.size()) {
  				base_scale = state.nodes[E->key()]->scale;
  			}
  
  			bool last = false;
  			while (true) {
  				Vector3 pos = base_pos;
  				Quat rot = base_rot;
  				Vector3 scale = base_scale;
  
  				if (track.translation_track.times.size()) {
  					pos = _interpolate_track<Vector3>(track.translation_track.times, track.translation_track.values, time, track.translation_track.interpolation);
  				}
  
  				if (track.rotation_track.times.size()) {
  					rot = _interpolate_track<Quat>(track.rotation_track.times, track.rotation_track.values, time, track.rotation_track.interpolation);
  				}
  
  				if (track.scale_track.times.size()) {
  					scale = _interpolate_track<Vector3>(track.scale_track.times, track.scale_track.values, time, track.scale_track.interpolation);
  				}
  
  				if (node->skeleton >= 0) {
  					Transform xform;
  					xform.basis.set_quat_scale(rot, scale);
  					xform.origin = pos;
  
  					const Skeleton3D *skeleton = state.skeletons[node->skeleton].godot_skeleton;
  					const int bone_idx = skeleton->find_bone(node->name);
  					xform = skeleton->get_bone_rest(bone_idx).affine_inverse() * xform;
  
  					rot = xform.basis.get_rotation_quat();
  					rot.normalize();
  					scale = xform.basis.get_scale();
  					pos = xform.origin;
  				}
  
  				animation->transform_track_insert_key(track_idx, time, pos, rot, scale);
  
  				if (last) {
  					break;
  				}
  				time += increment;
  				if (time >= length) {
  					last = true;
  					time = length;
  				}
  			}
  		}
  
  		for (int i = 0; i < track.weight_tracks.size(); i++) {
  			ERR_CONTINUE(node->mesh < 0 || node->mesh >= state.meshes.size());
  			const GLTFMesh &mesh = state.meshes[node->mesh];
  			const String prop = "blend_shapes/" + mesh.mesh->get_blend_shape_name(i);
  
  			const String blend_path = String(node_path) + ":" + prop;
  
  			const int track_idx = animation->get_track_count();
  			animation->add_track(Animation::TYPE_VALUE);
  			animation->track_set_path(track_idx, blend_path);
  
  			// Only LINEAR and STEP (NEAREST) can be supported out of the box by Godot's Animation,
  			// the other modes have to be baked.
  			GLTFAnimation::Interpolation gltf_interp = track.weight_tracks[i].interpolation;
  			if (gltf_interp == GLTFAnimation::INTERP_LINEAR || gltf_interp == GLTFAnimation::INTERP_STEP) {
  				animation->track_set_interpolation_type(track_idx, gltf_interp == GLTFAnimation::INTERP_STEP ? Animation::INTERPOLATION_NEAREST : Animation::INTERPOLATION_LINEAR);
  				for (int j = 0; j < track.weight_tracks[i].times.size(); j++) {
  					const float t = track.weight_tracks[i].times[j];
  					const float w = track.weight_tracks[i].values[j];
  					animation->track_insert_key(track_idx, t, w);
  				}
  			} else {
  				// CATMULLROMSPLINE or CUBIC_SPLINE have to be baked, apologies.
  				const float increment = 1.0 / float(bake_fps);
  				float time = 0.0;
  				bool last = false;
  				while (true) {
  					_interpolate_track<float>(track.weight_tracks[i].times, track.weight_tracks[i].values, time, gltf_interp);
  					if (last) {
  						break;
  					}
  					time += increment;
  					if (time >= length) {
  						last = true;
  						time = length;
  					}
  				}
  			}
  		}
  	}
  
  	animation->set_length(length);
  
  	ap->add_animation(name, animation);
  }
  
  void EditorSceneImporterGLTF::_process_mesh_instances(GLTFState &state, Node3D *scene_root) {
  	for (GLTFNodeIndex node_i = 0; node_i < state.nodes.size(); ++node_i) {
  		const GLTFNode *node = state.nodes[node_i];
  
  		if (node->skin >= 0 && node->mesh >= 0) {
  			const GLTFSkinIndex skin_i = node->skin;
  
  			Map<GLTFNodeIndex, Node *>::Element *mi_element = state.scene_nodes.find(node_i);
  			MeshInstance3D *mi = Object::cast_to<MeshInstance3D>(mi_element->get());
  			ERR_FAIL_COND(mi == nullptr);
  
  			const GLTFSkeletonIndex skel_i = state.skins[node->skin].skeleton;
  			const GLTFSkeleton &gltf_skeleton = state.skeletons[skel_i];
  			Skeleton3D *skeleton = gltf_skeleton.godot_skeleton;
  			ERR_FAIL_COND(skeleton == nullptr);
  
  			mi->get_parent()->remove_child(mi);
  			skeleton->add_child(mi);
  			mi->set_owner(scene_root);
  
  			mi->set_skin(state.skins[skin_i].godot_skin);
  			mi->set_skeleton_path(mi->get_path_to(skeleton));
  			mi->set_transform(Transform());
  		}
  	}
  }
  
  Node3D *EditorSceneImporterGLTF::_generate_scene(GLTFState &state, const int p_bake_fps) {
  	Node3D *root = memnew(Node3D);
  
  	// scene_name is already unique
  	root->set_name(state.scene_name);
  
  	for (int i = 0; i < state.root_nodes.size(); ++i) {
  		_generate_scene_node(state, root, root, state.root_nodes[i]);
  	}
  
  	_process_mesh_instances(state, root);
  
  	if (state.animations.size()) {
  		AnimationPlayer *ap = memnew(AnimationPlayer);
  		ap->set_name("AnimationPlayer");
  		root->add_child(ap);
  		ap->set_owner(root);
  
  		for (int i = 0; i < state.animations.size(); i++) {
  			_import_animation(state, ap, i, p_bake_fps);
  		}
  	}
  
  	return root;
  }
  
  Node *EditorSceneImporterGLTF::import_scene(const String &p_path, uint32_t p_flags, int p_bake_fps, List<String> *r_missing_deps, Error *r_err) {
  	GLTFState state;
  
  	if (p_path.to_lower().ends_with("glb")) {
  		//binary file
  		//text file
  		Error err = _parse_glb(p_path, state);
  		if (err) {
  			return nullptr;
  		}
  	} else {
  		//text file
  		Error err = _parse_json(p_path, state);
  		if (err) {
  			return nullptr;
  		}
  	}
  
  	ERR_FAIL_COND_V(!state.json.has("asset"), nullptr);
  
  	Dictionary asset = state.json["asset"];
  
  	ERR_FAIL_COND_V(!asset.has("version"), nullptr);
  
  	String version = asset["version"];
  
  	state.import_flags = p_flags;
  	state.major_version = version.get_slice(".", 0).to_int();
  	state.minor_version = version.get_slice(".", 1).to_int();
  	state.use_named_skin_binds = p_flags & IMPORT_USE_NAMED_SKIN_BINDS;
  
  	/* STEP 0 PARSE SCENE */
  	Error err = _parse_scenes(state);
  	if (err != OK) {
  		return nullptr;
  	}
  
  	/* STEP 1 PARSE NODES */
  	err = _parse_nodes(state);
  	if (err != OK) {
  		return nullptr;
  	}
  
  	/* STEP 2 PARSE BUFFERS */
  	err = _parse_buffers(state, p_path.get_base_dir());
  	if (err != OK) {
  		return nullptr;
  	}
  
  	/* STEP 3 PARSE BUFFER VIEWS */
  	err = _parse_buffer_views(state);
  	if (err != OK) {
  		return nullptr;
  	}
  
  	/* STEP 4 PARSE ACCESSORS */
  	err = _parse_accessors(state);
  	if (err != OK) {
  		return nullptr;
  	}
  
  	/* STEP 5 PARSE IMAGES */
  	err = _parse_images(state, p_path.get_base_dir());
  	if (err != OK) {
  		return nullptr;
  	}
  
  	/* STEP 6 PARSE TEXTURES */
  	err = _parse_textures(state);
  	if (err != OK) {
  		return nullptr;
  	}
  
  	/* STEP 7 PARSE TEXTURES */
  	err = _parse_materials(state);
  	if (err != OK) {
  		return nullptr;
  	}
  
  	/* STEP 9 PARSE SKINS */
  	err = _parse_skins(state);
  	if (err != OK) {
  		return nullptr;
  	}
  
  	/* STEP 10 DETERMINE SKELETONS */
  	err = _determine_skeletons(state);
  	if (err != OK) {
  		return nullptr;
  	}
  
  	/* STEP 11 CREATE SKELETONS */
  	err = _create_skeletons(state);
  	if (err != OK) {
  		return nullptr;
  	}
  
  	/* STEP 12 CREATE SKINS */
  	err = _create_skins(state);
  	if (err != OK) {
  		return nullptr;
  	}
  
  	/* STEP 13 PARSE MESHES (we have enough info now) */
  	err = _parse_meshes(state);
  	if (err != OK) {
  		return nullptr;
  	}
  
  	/* STEP 14 PARSE LIGHTS */
  	err = _parse_lights(state);
  	if (err != OK) {
  		return NULL;
  	}
  
  	/* STEP 15 PARSE CAMERAS */
  	err = _parse_cameras(state);
  	if (err != OK) {
  		return nullptr;
  	}
  
  	/* STEP 16 PARSE ANIMATIONS */
  	err = _parse_animations(state);
  	if (err != OK) {
  		return nullptr;
  	}
  
  	/* STEP 17 ASSIGN SCENE NAMES */
  	_assign_scene_names(state);
  
  	/* STEP 18 MAKE SCENE! */
  	Node3D *scene = _generate_scene(state, p_bake_fps);
  
  	return scene;
  }
  
  Ref<Animation> EditorSceneImporterGLTF::import_animation(const String &p_path, uint32_t p_flags, int p_bake_fps) {
  	return Ref<Animation>();
  }
  
  EditorSceneImporterGLTF::EditorSceneImporterGLTF() {
  }
  