Merge pull request #44499 from RevoluPowered/fbx_plugin_port_4.0

[fbx] Port FBX module from 3.2 branch

1 files changed, 713 insertions, 0 deletions

diff --git a/modules/fbx/fbx_parser/FBXDocument.cpp b/modules/fbx/fbx_parser/FBXDocument.cpp
new file mode 100644
index 0000000000..74798a655a
--- /dev/null
+++ b/modules/fbx/fbx_parser/FBXDocument.cpp
@@ -0,0 +1,713 @@
+/*************************************************************************/
+/*  FBXDocument.cpp                                                      */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2020 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2020 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+/*
+Open Asset Import Library (assimp)
+----------------------------------------------------------------------
+
+Copyright (c) 2006-2019, assimp team
+
+All rights reserved.
+
+Redistribution and use of this software in source and binary forms,
+with or without modification, are permitted provided that the
+following conditions are met:
+
+* Redistributions of source code must retain the above
+  copyright notice, this list of conditions and the
+  following disclaimer.
+
+* Redistributions in binary form must reproduce the above
+  copyright notice, this list of conditions and the*
+  following disclaimer in the documentation and/or other
+  materials provided with the distribution.
+
+* Neither the name of the assimp team, nor the names of its
+  contributors may be used to endorse or promote products
+  derived from this software without specific prior
+  written permission of the assimp team.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+----------------------------------------------------------------------
+*/
+
+/** @file  FBXDocument.cpp
+ *  @brief Implementation of the FBX DOM classes
+ */
+
+#include "FBXDocument.h"
+#include "FBXDocumentUtil.h"
+#include "FBXImportSettings.h"
+#include "FBXMeshGeometry.h"
+#include "FBXParser.h"
+#include "FBXProperties.h"
+#include "FBXUtil.h"
+
+#include <algorithm>
+#include <functional>
+#include <iostream>
+#include <map>
+#include <memory>
+
+namespace FBXDocParser {
+
+using namespace Util;
+
+// ------------------------------------------------------------------------------------------------
+LazyObject::LazyObject(uint64_t id, const ElementPtr element, const Document &doc) :
+		doc(doc), element(element), id(id), flags() {
+	// empty
+}
+
+// ------------------------------------------------------------------------------------------------
+LazyObject::~LazyObject() {
+	object.reset();
+}
+
+ObjectPtr LazyObject::LoadObject() {
+	if (IsBeingConstructed() || FailedToConstruct()) {
+		return nullptr;
+	}
+
+	if (object) {
+		return object.get();
+	}
+
+	TokenPtr key = element->KeyToken();
+	ERR_FAIL_COND_V(!key, nullptr);
+	const TokenList &tokens = element->Tokens();
+
+	if (tokens.size() < 3) {
+		//DOMError("expected at least 3 tokens: id, name and class tag",&element);
+		return nullptr;
+	}
+
+	const char *err = nullptr;
+	std::string name = ParseTokenAsString(tokens[1], err);
+	if (err) {
+		DOMError(err, element);
+	}
+
+	// small fix for binary reading: binary fbx files don't use
+	// prefixes such as Model:: in front of their names. The
+	// loading code expects this at many places, though!
+	// so convert the binary representation (a 0x0001) to the
+	// double colon notation.
+	if (tokens[1]->IsBinary()) {
+		for (size_t i = 0; i < name.length(); ++i) {
+			if (name[i] == 0x0 && name[i + 1] == 0x1) {
+				name = name.substr(i + 2) + "::" + name.substr(0, i);
+			}
+		}
+	}
+
+	const std::string classtag = ParseTokenAsString(tokens[2], err);
+	if (err) {
+		DOMError(err, element);
+	}
+
+	// prevent recursive calls
+	flags |= BEING_CONSTRUCTED;
+
+	// this needs to be relatively fast since it happens a lot,
+	// so avoid constructing strings all the time.
+	const char *obtype = key->begin();
+	const size_t length = static_cast<size_t>(key->end() - key->begin());
+
+	if (!strncmp(obtype, "Pose", length)) {
+		object.reset(new FbxPose(id, element, doc, name));
+	} else if (!strncmp(obtype, "Geometry", length)) {
+		if (!strcmp(classtag.c_str(), "Mesh")) {
+			object.reset(new MeshGeometry(id, element, name, doc));
+		}
+		if (!strcmp(classtag.c_str(), "Shape")) {
+			object.reset(new ShapeGeometry(id, element, name, doc));
+		}
+		if (!strcmp(classtag.c_str(), "Line")) {
+			object.reset(new LineGeometry(id, element, name, doc));
+		}
+	} else if (!strncmp(obtype, "NodeAttribute", length)) {
+		if (!strcmp(classtag.c_str(), "Camera")) {
+			object.reset(new Camera(id, element, doc, name));
+		} else if (!strcmp(classtag.c_str(), "CameraSwitcher")) {
+			object.reset(new CameraSwitcher(id, element, doc, name));
+		} else if (!strcmp(classtag.c_str(), "Light")) {
+			object.reset(new Light(id, element, doc, name));
+		} else if (!strcmp(classtag.c_str(), "Null")) {
+			object.reset(new Null(id, element, doc, name));
+		} else if (!strcmp(classtag.c_str(), "LimbNode")) {
+			// This is an older format for bones
+			// this is what blender uses I believe
+			object.reset(new LimbNode(id, element, doc, name));
+		}
+	} else if (!strncmp(obtype, "Constraint", length)) {
+		object.reset(new Constraint(id, element, doc, name));
+	} else if (!strncmp(obtype, "Deformer", length)) {
+		if (!strcmp(classtag.c_str(), "Cluster")) {
+			object.reset(new Cluster(id, element, doc, name));
+		} else if (!strcmp(classtag.c_str(), "Skin")) {
+			object.reset(new Skin(id, element, doc, name));
+		} else if (!strcmp(classtag.c_str(), "BlendShape")) {
+			object.reset(new BlendShape(id, element, doc, name));
+		} else if (!strcmp(classtag.c_str(), "BlendShapeChannel")) {
+			object.reset(new BlendShapeChannel(id, element, doc, name));
+		}
+	} else if (!strncmp(obtype, "Model", length)) {
+		// Model is normal node
+
+		// LimbNode model is a 'bone' node.
+		if (!strcmp(classtag.c_str(), "LimbNode")) {
+			object.reset(new ModelLimbNode(id, element, doc, name));
+
+		} else if (strcmp(classtag.c_str(), "IKEffector") && strcmp(classtag.c_str(), "FKEffector")) {
+			// FK and IK effectors are not supporte
+			object.reset(new Model(id, element, doc, name));
+		}
+	} else if (!strncmp(obtype, "Material", length)) {
+		object.reset(new Material(id, element, doc, name));
+	} else if (!strncmp(obtype, "Texture", length)) {
+		object.reset(new Texture(id, element, doc, name));
+	} else if (!strncmp(obtype, "LayeredTexture", length)) {
+		object.reset(new LayeredTexture(id, element, doc, name));
+	} else if (!strncmp(obtype, "Video", length)) {
+		object.reset(new Video(id, element, doc, name));
+	} else if (!strncmp(obtype, "AnimationStack", length)) {
+		object.reset(new AnimationStack(id, element, name, doc));
+	} else if (!strncmp(obtype, "AnimationLayer", length)) {
+		object.reset(new AnimationLayer(id, element, name, doc));
+	} else if (!strncmp(obtype, "AnimationCurve", length)) {
+		object.reset(new AnimationCurve(id, element, name, doc));
+	} else if (!strncmp(obtype, "AnimationCurveNode", length)) {
+		object.reset(new AnimationCurveNode(id, element, name, doc));
+	} else {
+		ERR_FAIL_V_MSG(nullptr, "FBX contains unsupported object: " + String(obtype));
+	}
+
+	flags &= ~BEING_CONSTRUCTED;
+
+	return object.get();
+}
+
+// ------------------------------------------------------------------------------------------------
+Object::Object(uint64_t id, const ElementPtr element, const std::string &name) :
+		element(element), name(name), id(id) {
+}
+
+// ------------------------------------------------------------------------------------------------
+Object::~Object() {
+	// empty
+}
+
+// ------------------------------------------------------------------------------------------------
+FileGlobalSettings::FileGlobalSettings(const Document &doc, const PropertyTable *props) :
+		props(props), doc(doc) {
+	// empty
+}
+
+// ------------------------------------------------------------------------------------------------
+FileGlobalSettings::~FileGlobalSettings() {
+	if (props != nullptr) {
+		delete props;
+		props = nullptr;
+	}
+}
+
+// ------------------------------------------------------------------------------------------------
+Document::Document(const Parser &parser, const ImportSettings &settings) :
+		settings(settings), parser(parser), SafeToImport(false) {
+	// Cannot use array default initialization syntax because vc8 fails on it
+	for (unsigned int &timeStamp : creationTimeStamp) {
+		timeStamp = 0;
+	}
+
+	// we must check if we can read the header version safely, if its outdated then drop it.
+	if (ReadHeader()) {
+		SafeToImport = true;
+		ReadPropertyTemplates();
+
+		ReadGlobalSettings();
+
+		// This order is important, connections need parsed objects to check
+		// whether connections are ok or not. Objects may not be evaluated yet,
+		// though, since this may require valid connections.
+		ReadObjects();
+		ReadConnections();
+	}
+}
+
+// ------------------------------------------------------------------------------------------------
+Document::~Document() {
+	for (PropertyTemplateMap::value_type v : templates) {
+		delete v.second;
+	}
+
+	for (ObjectMap::value_type &v : objects) {
+		delete v.second;
+	}
+
+	for (ConnectionMap::value_type &v : src_connections) {
+		delete v.second;
+	}
+
+	if (metadata_properties != nullptr) {
+		delete metadata_properties;
+	}
+	// clear globals import pointer
+	globals.reset();
+}
+
+// ------------------------------------------------------------------------------------------------
+static const unsigned int LowerSupportedVersion = 7300;
+static const unsigned int UpperSupportedVersion = 7700;
+
+bool Document::ReadHeader() {
+	// Read ID objects from "Objects" section
+	ScopePtr sc = parser.GetRootScope();
+	ElementPtr ehead = sc->GetElement("FBXHeaderExtension");
+	if (!ehead || !ehead->Compound()) {
+		DOMError("no FBXHeaderExtension dictionary found");
+	}
+
+	const ScopePtr shead = ehead->Compound();
+	fbxVersion = ParseTokenAsInt(GetRequiredToken(GetRequiredElement(shead, "FBXVersion", ehead), 0));
+
+	// While we may have some success with newer files, we don't support
+	// the older 6.n fbx format
+	if (fbxVersion < LowerSupportedVersion) {
+		DOMWarning("unsupported, old format version, FBX 2015-2020, you must re-export in a more modern version of your original modelling application");
+		return false;
+	}
+	if (fbxVersion > UpperSupportedVersion) {
+		DOMWarning("unsupported, newer format version, supported are only FBX 2015, up to FBX 2020"
+				   " trying to read it nevertheless");
+	}
+
+	const ElementPtr ecreator = shead->GetElement("Creator");
+	if (ecreator) {
+		creator = ParseTokenAsString(GetRequiredToken(ecreator, 0));
+	}
+
+	//
+	// Scene Info
+	//
+
+	const ElementPtr scene_info = shead->GetElement("SceneInfo");
+
+	if (scene_info) {
+		PropertyTable *fileExportProps = const_cast<PropertyTable *>(GetPropertyTable(*this, "", scene_info, scene_info->Compound(), true));
+
+		if (fileExportProps) {
+			metadata_properties = fileExportProps;
+		}
+	}
+
+	const ElementPtr etimestamp = shead->GetElement("CreationTimeStamp");
+	if (etimestamp && etimestamp->Compound()) {
+		const ScopePtr stimestamp = etimestamp->Compound();
+		creationTimeStamp[0] = ParseTokenAsInt(GetRequiredToken(GetRequiredElement(stimestamp, "Year"), 0));
+		creationTimeStamp[1] = ParseTokenAsInt(GetRequiredToken(GetRequiredElement(stimestamp, "Month"), 0));
+		creationTimeStamp[2] = ParseTokenAsInt(GetRequiredToken(GetRequiredElement(stimestamp, "Day"), 0));
+		creationTimeStamp[3] = ParseTokenAsInt(GetRequiredToken(GetRequiredElement(stimestamp, "Hour"), 0));
+		creationTimeStamp[4] = ParseTokenAsInt(GetRequiredToken(GetRequiredElement(stimestamp, "Minute"), 0));
+		creationTimeStamp[5] = ParseTokenAsInt(GetRequiredToken(GetRequiredElement(stimestamp, "Second"), 0));
+		creationTimeStamp[6] = ParseTokenAsInt(GetRequiredToken(GetRequiredElement(stimestamp, "Millisecond"), 0));
+	}
+
+	return true;
+}
+
+// ------------------------------------------------------------------------------------------------
+void Document::ReadGlobalSettings() {
+	ERR_FAIL_COND_MSG(globals != nullptr, "Global settings is already setup this is a serious error and should be reported");
+
+	const ScopePtr sc = parser.GetRootScope();
+	const ElementPtr ehead = sc->GetElement("GlobalSettings");
+	if (nullptr == ehead || !ehead->Compound()) {
+		DOMWarning("no GlobalSettings dictionary found");
+		globals = std::make_shared<FileGlobalSettings>(*this, new PropertyTable());
+		return;
+	}
+
+	const PropertyTable *props = GetPropertyTable(*this, "", ehead, ehead->Compound(), true);
+
+	//double v = PropertyGet<float>( *props, std::string("UnitScaleFactor"), 1.0 );
+
+	if (!props) {
+		DOMError("GlobalSettings dictionary contains no property table");
+	}
+
+	globals = std::make_shared<FileGlobalSettings>(*this, props);
+}
+
+// ------------------------------------------------------------------------------------------------
+void Document::ReadObjects() {
+	// read ID objects from "Objects" section
+	const ScopePtr sc = parser.GetRootScope();
+	const ElementPtr eobjects = sc->GetElement("Objects");
+	if (!eobjects || !eobjects->Compound()) {
+		DOMError("no Objects dictionary found");
+	}
+
+	// add a dummy entry to represent the Model::RootNode object (id 0),
+	// which is only indirectly defined in the input file
+	objects[0] = new LazyObject(0L, eobjects, *this);
+
+	const ScopePtr sobjects = eobjects->Compound();
+	for (const ElementMap::value_type &iter : sobjects->Elements()) {
+		// extract ID
+		const TokenList &tok = iter.second->Tokens();
+
+		if (tok.empty()) {
+			DOMError("expected ID after object key", iter.second);
+		}
+
+		const char *err;
+		const uint64_t id = ParseTokenAsID(tok[0], err);
+		if (err) {
+			DOMError(err, iter.second);
+		}
+
+		// id=0 is normally implicit
+		if (id == 0L) {
+			DOMError("encountered object with implicitly defined id 0", iter.second);
+		}
+
+		if (objects.find(id) != objects.end()) {
+			DOMWarning("encountered duplicate object id, ignoring first occurrence", iter.second);
+		}
+
+		objects[id] = new LazyObject(id, iter.second, *this);
+
+		// grab all animation stacks upfront since there is no listing of them
+		if (!strcmp(iter.first.c_str(), "AnimationStack")) {
+			animationStacks.push_back(id);
+		} else if (!strcmp(iter.first.c_str(), "Constraint")) {
+			constraints.push_back(id);
+		} else if (!strcmp(iter.first.c_str(), "Pose")) {
+			bind_poses.push_back(id);
+		} else if (!strcmp(iter.first.c_str(), "Material")) {
+			materials.push_back(id);
+		} else if (!strcmp(iter.first.c_str(), "Deformer")) {
+			TokenPtr key = iter.second->KeyToken();
+			ERR_CONTINUE_MSG(!key, "[parser bug] invalid token key for deformer");
+			const TokenList &tokens = iter.second->Tokens();
+			const std::string class_tag = ParseTokenAsString(tokens[2], err);
+
+			if (err) {
+				DOMError(err, iter.second);
+			}
+
+			if (class_tag == "Skin") {
+				//print_verbose("registered skin:" + itos(id));
+				skins.push_back(id);
+			}
+		}
+	}
+}
+
+// ------------------------------------------------------------------------------------------------
+void Document::ReadPropertyTemplates() {
+	const ScopePtr sc = parser.GetRootScope();
+	// read property templates from "Definitions" section
+	const ElementPtr edefs = sc->GetElement("Definitions");
+	if (!edefs || !edefs->Compound()) {
+		DOMWarning("no Definitions dictionary found");
+		return;
+	}
+
+	const ScopePtr sdefs = edefs->Compound();
+	const ElementCollection otypes = sdefs->GetCollection("ObjectType");
+	for (ElementMap::const_iterator it = otypes.first; it != otypes.second; ++it) {
+		const ElementPtr el = (*it).second;
+		const ScopePtr sc_2 = el->Compound();
+		if (!sc_2) {
+			DOMWarning("expected nested scope in ObjectType, ignoring", el);
+			continue;
+		}
+
+		const TokenList &tok = el->Tokens();
+		if (tok.empty()) {
+			DOMWarning("expected name for ObjectType element, ignoring", el);
+			continue;
+		}
+
+		const std::string &oname = ParseTokenAsString(tok[0]);
+
+		const ElementCollection templs = sc_2->GetCollection("PropertyTemplate");
+		for (ElementMap::const_iterator iter = templs.first; iter != templs.second; ++iter) {
+			const ElementPtr el_2 = (*iter).second;
+			const ScopePtr sc_3 = el_2->Compound();
+			if (!sc_3) {
+				DOMWarning("expected nested scope in PropertyTemplate, ignoring", el);
+				continue;
+			}
+
+			const TokenList &tok_2 = el_2->Tokens();
+			if (tok_2.empty()) {
+				DOMWarning("expected name for PropertyTemplate element, ignoring", el);
+				continue;
+			}
+
+			const std::string &pname = ParseTokenAsString(tok_2[0]);
+
+			const ElementPtr Properties70 = sc_3->GetElement("Properties70");
+			if (Properties70) {
+				// PropertyTable(const ElementPtr element, const PropertyTable* templateProps);
+				const PropertyTable *props = new PropertyTable(Properties70, nullptr);
+
+				templates[oname + "." + pname] = props;
+			}
+		}
+	}
+}
+
+// ------------------------------------------------------------------------------------------------
+void Document::ReadConnections() {
+	const ScopePtr sc = parser.GetRootScope();
+
+	// read property templates from "Definitions" section
+	const ElementPtr econns = sc->GetElement("Connections");
+	if (!econns || !econns->Compound()) {
+		DOMError("no Connections dictionary found");
+	}
+
+	uint64_t insertionOrder = 0l;
+	const ScopePtr sconns = econns->Compound();
+	const ElementCollection conns = sconns->GetCollection("C");
+	for (ElementMap::const_iterator it = conns.first; it != conns.second; ++it) {
+		const ElementPtr el = (*it).second;
+		const std::string &type = ParseTokenAsString(GetRequiredToken(el, 0));
+
+		// PP = property-property connection, ignored for now
+		// (tokens: "PP", ID1, "Property1", ID2, "Property2")
+		if (type == "PP") {
+			continue;
+		}
+
+		const uint64_t src = ParseTokenAsID(GetRequiredToken(el, 1));
+		const uint64_t dest = ParseTokenAsID(GetRequiredToken(el, 2));
+
+		// OO = object-object connection
+		// OP = object-property connection, in which case the destination property follows the object ID
+		const std::string &prop = (type == "OP" ? ParseTokenAsString(GetRequiredToken(el, 3)) : "");
+
+		if (objects.find(src) == objects.end()) {
+			DOMWarning("source object for connection does not exist", el);
+			continue;
+		}
+
+		// dest may be 0 (root node) but we added a dummy object before
+		if (objects.find(dest) == objects.end()) {
+			DOMWarning("destination object for connection does not exist", el);
+			continue;
+		}
+
+		// add new connection
+		const Connection *const c = new Connection(insertionOrder++, src, dest, prop, *this);
+		src_connections.insert(ConnectionMap::value_type(src, c));
+		dest_connections.insert(ConnectionMap::value_type(dest, c));
+	}
+}
+
+// ------------------------------------------------------------------------------------------------
+const std::vector<const AnimationStack *> &Document::AnimationStacks() const {
+	if (!animationStacksResolved.empty() || animationStacks.empty()) {
+		return animationStacksResolved;
+	}
+
+	animationStacksResolved.reserve(animationStacks.size());
+	for (uint64_t id : animationStacks) {
+		LazyObject *lazy = GetObject(id);
+
+		// Two things happen here:
+		// We cast internally an Object PTR to an Animation Stack PTR
+		// We return invalid weak_ptrs for objects which are invalid
+
+		const AnimationStack *stack = lazy->Get<AnimationStack>();
+		ERR_CONTINUE_MSG(!stack, "invalid ptr to AnimationStack - conversion failure");
+
+		// We push back the weak reference :) to keep things simple, as ownership is on the parser side so it wont be cleaned up.
+		animationStacksResolved.push_back(stack);
+	}
+
+	return animationStacksResolved;
+}
+
+// ------------------------------------------------------------------------------------------------
+LazyObject *Document::GetObject(uint64_t id) const {
+	ObjectMap::const_iterator it = objects.find(id);
+	return it == objects.end() ? nullptr : (*it).second;
+}
+
+#define MAX_CLASSNAMES 6
+
+// ------------------------------------------------------------------------------------------------
+std::vector<const Connection *> Document::GetConnectionsSequenced(uint64_t id, const ConnectionMap &conns) const {
+	std::vector<const Connection *> temp;
+
+	const std::pair<ConnectionMap::const_iterator, ConnectionMap::const_iterator> range =
+			conns.equal_range(id);
+
+	temp.reserve(std::distance(range.first, range.second));
+	for (ConnectionMap::const_iterator it = range.first; it != range.second; ++it) {
+		temp.push_back((*it).second);
+	}
+
+	std::sort(temp.begin(), temp.end(), std::mem_fn(&Connection::Compare));
+
+	return temp; // NRVO should handle this
+}
+
+// ------------------------------------------------------------------------------------------------
+std::vector<const Connection *> Document::GetConnectionsSequenced(uint64_t id, bool is_src,
+		const ConnectionMap &conns,
+		const char *const *classnames,
+		size_t count) const
+
+{
+	size_t lengths[MAX_CLASSNAMES];
+
+	const size_t c = count;
+	for (size_t i = 0; i < c; ++i) {
+		lengths[i] = strlen(classnames[i]);
+	}
+
+	std::vector<const Connection *> temp;
+	const std::pair<ConnectionMap::const_iterator, ConnectionMap::const_iterator> range =
+			conns.equal_range(id);
+
+	temp.reserve(std::distance(range.first, range.second));
+	for (ConnectionMap::const_iterator it = range.first; it != range.second; ++it) {
+		TokenPtr key = (is_src ? (*it).second->LazyDestinationObject() : (*it).second->LazySourceObject())->GetElement()->KeyToken();
+
+		const char *obtype = key->begin();
+
+		for (size_t i = 0; i < c; ++i) {
+			//ai_assert(classnames[i]);
+			if (static_cast<size_t>(std::distance(key->begin(), key->end())) == lengths[i] && !strncmp(classnames[i], obtype, lengths[i])) {
+				obtype = nullptr;
+				break;
+			}
+		}
+
+		if (obtype) {
+			continue;
+		}
+
+		temp.push_back((*it).second);
+	}
+
+	std::sort(temp.begin(), temp.end(), std::mem_fn(&Connection::Compare));
+	return temp; // NRVO should handle this
+}
+
+// ------------------------------------------------------------------------------------------------
+std::vector<const Connection *> Document::GetConnectionsBySourceSequenced(uint64_t source) const {
+	return GetConnectionsSequenced(source, ConnectionsBySource());
+}
+
+// ------------------------------------------------------------------------------------------------
+std::vector<const Connection *> Document::GetConnectionsBySourceSequenced(uint64_t src, const char *classname) const {
+	const char *arr[] = { classname };
+	return GetConnectionsBySourceSequenced(src, arr, 1);
+}
+
+// ------------------------------------------------------------------------------------------------
+std::vector<const Connection *> Document::GetConnectionsBySourceSequenced(uint64_t source,
+		const char *const *classnames, size_t count) const {
+	return GetConnectionsSequenced(source, true, ConnectionsBySource(), classnames, count);
+}
+
+// ------------------------------------------------------------------------------------------------
+std::vector<const Connection *> Document::GetConnectionsByDestinationSequenced(uint64_t dest,
+		const char *classname) const {
+	const char *arr[] = { classname };
+	return GetConnectionsByDestinationSequenced(dest, arr, 1);
+}
+
+// ------------------------------------------------------------------------------------------------
+std::vector<const Connection *> Document::GetConnectionsByDestinationSequenced(uint64_t dest) const {
+	return GetConnectionsSequenced(dest, ConnectionsByDestination());
+}
+
+// ------------------------------------------------------------------------------------------------
+std::vector<const Connection *> Document::GetConnectionsByDestinationSequenced(uint64_t dest,
+		const char *const *classnames, size_t count) const {
+	return GetConnectionsSequenced(dest, false, ConnectionsByDestination(), classnames, count);
+}
+
+// ------------------------------------------------------------------------------------------------
+Connection::Connection(uint64_t insertionOrder, uint64_t src, uint64_t dest, const std::string &prop,
+		const Document &doc) :
+		insertionOrder(insertionOrder), prop(prop), src(src), dest(dest), doc(doc) {
+}
+
+// ------------------------------------------------------------------------------------------------
+Connection::~Connection() {
+	// empty
+}
+
+// ------------------------------------------------------------------------------------------------
+LazyObject *Connection::LazySourceObject() const {
+	LazyObject *const lazy = doc.GetObject(src);
+	return lazy;
+}
+
+// ------------------------------------------------------------------------------------------------
+LazyObject *Connection::LazyDestinationObject() const {
+	LazyObject *const lazy = doc.GetObject(dest);
+	return lazy;
+}
+
+// ------------------------------------------------------------------------------------------------
+Object *Connection::SourceObject() const {
+	LazyObject *lazy = doc.GetObject(src);
+	//ai_assert(lazy);
+	return lazy->LoadObject();
+}
+
+// ------------------------------------------------------------------------------------------------
+Object *Connection::DestinationObject() const {
+	LazyObject *lazy = doc.GetObject(dest);
+	//ai_assert(lazy);
+	return lazy->LoadObject();
+}
+} // namespace FBXDocParser