diff --git a/CMakeLists.txt b/CMakeLists.txt
index 64d63d3..e840de0 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,6 +1,6 @@
 cmake_minimum_required(VERSION 3.12)
 
-set(IRRLICHTMT_REVISION 14)
+set(IRRLICHTMT_REVISION 15)
 
 project(Irrlicht
 	VERSION 1.9.0.${IRRLICHTMT_REVISION}
diff --git a/include/ISceneNode.h b/include/ISceneNode.h
index f963aca..ab1a0fc 100644
--- a/include/ISceneNode.h
+++ b/include/ISceneNode.h
@@ -14,6 +14,7 @@
 #include "aabbox3d.h"
 #include "matrix4.h"
 #include "IAttributes.h"
+
 #include <list>
 #include <optional>
 
@@ -117,23 +118,14 @@ namespace scene
 
 		//! Returns the name of the node.
 		/** \return Name as character string. */
-		virtual const c8* getName() const
+		virtual const std::optional<std::string> &getName() const
 		{
-			return Name.c_str();
+			return Name;
 		}
 
-
 		//! Sets the name of the node.
 		/** \param name New name of the scene node. */
-		virtual void setName(const c8* name)
-		{
-			Name = name;
-		}
-
-
-		//! Sets the name of the node.
-		/** \param name New name of the scene node. */
-		virtual void setName(const core::stringc& name)
+		virtual void setName(const std::optional<std::string> &name)
 		{
 			Name = name;
 		}
@@ -601,7 +593,7 @@ namespace scene
 		}
 
 		//! Name of the scene node.
-		core::stringc Name;
+		std::optional<std::string> Name;
 
 		//! Absolute transformation of the node.
 		core::matrix4 AbsoluteTransformation;
diff --git a/include/ISkinnedMesh.h b/include/ISkinnedMesh.h
index b946bf7..7782185 100644
--- a/include/ISkinnedMesh.h
+++ b/include/ISkinnedMesh.h
@@ -10,6 +10,8 @@
 #include "IAnimatedMesh.h"
 #include "SSkinMeshBuffer.h"
 
+#include <optional>
+
 namespace irr
 {
 namespace scene
@@ -41,12 +43,12 @@ namespace scene
 		/** \param number: Zero based index of joint. The last joint
 		has the number getJointCount()-1;
 		\return Name of joint and null if an error happened. */
-		virtual const c8* getJointName(u32 number) const = 0;
+		virtual const std::optional<std::string> &getJointName(u32 number) const = 0;
 
 		//! Gets a joint number from its name
 		/** \param name: Name of the joint.
-		\return Number of the joint or -1 if not found. */
-		virtual s32 getJointNumber(const c8* name) const = 0;
+		\return Number of the joint or std::nullopt if not found. */
+		virtual std::optional<u32> getJointNumber(const std::string &name) const = 0;
 
 		//! Use animation from another mesh
 		/** The animation is linked (not copied) based on joint names
@@ -136,7 +138,7 @@ namespace scene
 			}
 
 			//! The name of this joint
-			core::stringc Name;
+			std::optional<std::string> Name;
 
 			//! Local matrix of this joint
 			core::matrix4 LocalMatrix;
diff --git a/include/IrrCompileConfig.h b/include/IrrCompileConfig.h
index 50b61eb..0375f54 100644
--- a/include/IrrCompileConfig.h
+++ b/include/IrrCompileConfig.h
@@ -5,8 +5,8 @@
 #pragma once
 
 //! Identifies the IrrlichtMt fork customized for the Minetest engine
-#define IRRLICHT_VERSION_MT_REVISION 14
-#define IRRLICHT_VERSION_MT "mt14"
+#define IRRLICHT_VERSION_MT_REVISION 15
+#define IRRLICHT_VERSION_MT "mt15"
 
 //! Irrlicht SDK Version
 #define IRRLICHT_VERSION_MAJOR 1
diff --git a/source/Irrlicht/CAnimatedMeshSceneNode.cpp b/source/Irrlicht/CAnimatedMeshSceneNode.cpp
index 965e7f1..3d66446 100644
--- a/source/Irrlicht/CAnimatedMeshSceneNode.cpp
+++ b/source/Irrlicht/CAnimatedMeshSceneNode.cpp
@@ -471,21 +471,21 @@ IBoneSceneNode* CAnimatedMeshSceneNode::getJointNode(const c8* jointName)
 
 	ISkinnedMesh *skinnedMesh=(ISkinnedMesh*)Mesh;
 
-	const s32 number = skinnedMesh->getJointNumber(jointName);
+	const std::optional<u32> number = skinnedMesh->getJointNumber(jointName);
 
-	if (number == -1)
+	if (!number.has_value())
 	{
 		os::Printer::log("Joint with specified name not found in skinned mesh", jointName, ELL_DEBUG);
 		return 0;
 	}
 
-	if ((s32)JointChildSceneNodes.size() <= number)
+	if (JointChildSceneNodes.size() <= *number)
 	{
 		os::Printer::log("Joint was found in mesh, but is not loaded into node", jointName, ELL_WARNING);
 		return 0;
 	}
 
-	return JointChildSceneNodes[number];
+	return JointChildSceneNodes[*number];
 }
 
 
diff --git a/source/Irrlicht/CB3DMeshFileLoader.cpp b/source/Irrlicht/CB3DMeshFileLoader.cpp
index f4b2619..85f76a4 100644
--- a/source/Irrlicht/CB3DMeshFileLoader.cpp
+++ b/source/Irrlicht/CB3DMeshFileLoader.cpp
@@ -12,6 +12,8 @@
 #include "IFileSystem.h"
 #include "os.h"
 
+#include <algorithm>
+
 #ifdef _DEBUG
 #define _B3D_READER_DEBUG
 #endif
@@ -149,7 +151,7 @@ bool CB3DMeshFileLoader::load()
 bool CB3DMeshFileLoader::readChunkNODE(CSkinnedMesh::SJoint *inJoint)
 {
 	CSkinnedMesh::SJoint *joint = AnimatedMesh->addJoint(inJoint);
-	readString(joint->Name);
+	joint->Name = readString();
 
 #ifdef _B3D_READER_DEBUG
 	core::stringc logStr;
@@ -818,8 +820,8 @@ bool CB3DMeshFileLoader::readChunkTEXS()
 		Textures.push_back(SB3dTexture());
 		SB3dTexture& B3dTexture = Textures.getLast();
 
-		readString(B3dTexture.TextureName);
-		B3dTexture.TextureName.replace('\\','/');
+		B3dTexture.TextureName = readString();
+		std::replace(B3dTexture.TextureName.begin(), B3dTexture.TextureName.end(), '\\', '/');
 #ifdef _B3D_READER_DEBUG
 		os::Printer::log("read Texture", B3dTexture.TextureName.c_str(), ELL_DEBUG);
 #endif
@@ -872,10 +874,9 @@ bool CB3DMeshFileLoader::readChunkBRUS()
 	{
 		// This is what blitz basic calls a brush, like a Irrlicht Material
 
-		core::stringc name;
-		readString(name);
+		auto name = readString();
 #ifdef _B3D_READER_DEBUG
-		os::Printer::log("read Material", name, ELL_DEBUG);
+		os::Printer::log("read Material", name.c_str(), ELL_DEBUG);
 #endif
 		Materials.push_back(SB3dMaterial());
 		SB3dMaterial& B3dMaterial=Materials.getLast();
@@ -1031,18 +1032,19 @@ bool CB3DMeshFileLoader::readChunkBRUS()
 }
 
 
-void CB3DMeshFileLoader::readString(core::stringc& newstring)
+std::string CB3DMeshFileLoader::readString()
 {
-	newstring="";
+	std::string newstring = "";
 	while (true)
 	{
 		c8 character;
 		if (B3DFile->read(&character, sizeof(character)) == 0)
-			return; // eof
+			break; // eof
 		if (character==0)
-			return;
-		newstring.append(character);
+			break;
+		newstring.push_back(character);
 	}
+	return newstring;
 }
 
 
diff --git a/source/Irrlicht/CB3DMeshFileLoader.h b/source/Irrlicht/CB3DMeshFileLoader.h
index 903c152..be5eeed 100644
--- a/source/Irrlicht/CB3DMeshFileLoader.h
+++ b/source/Irrlicht/CB3DMeshFileLoader.h
@@ -52,7 +52,7 @@ private:
 	bool readChunkTEXS();
 	bool readChunkBRUS();
 
-	void readString(core::stringc& newstring);
+	std::string readString();
 	void readFloats(f32* vec, u32 count);
 
 	core::array<SB3dChunk> B3dStack;
diff --git a/source/Irrlicht/CBoneSceneNode.cpp b/source/Irrlicht/CBoneSceneNode.cpp
index f917b1b..0df5b80 100644
--- a/source/Irrlicht/CBoneSceneNode.cpp
+++ b/source/Irrlicht/CBoneSceneNode.cpp
@@ -4,6 +4,8 @@
 
 #include "CBoneSceneNode.h"
 
+#include <optional>
+
 namespace irr
 {
 namespace scene
@@ -11,7 +13,7 @@ namespace scene
 
 //! constructor
 CBoneSceneNode::CBoneSceneNode(ISceneNode* parent, ISceneManager* mgr, s32 id,
-	u32 boneIndex, const c8* boneName)
+	u32 boneIndex, const std::optional<std::string> &boneName)
 : IBoneSceneNode(parent, mgr, id), BoneIndex(boneIndex),
 	AnimationMode(EBAM_AUTOMATIC), SkinningSpace(EBSS_LOCAL)
 {
diff --git a/source/Irrlicht/CBoneSceneNode.h b/source/Irrlicht/CBoneSceneNode.h
index 7c81421..4b47095 100644
--- a/source/Irrlicht/CBoneSceneNode.h
+++ b/source/Irrlicht/CBoneSceneNode.h
@@ -8,6 +8,8 @@
 
 #include "IBoneSceneNode.h"
 
+#include <optional>
+
 namespace irr
 {
 namespace scene
@@ -19,7 +21,8 @@ namespace scene
 
 		//! constructor
 		CBoneSceneNode(ISceneNode* parent, ISceneManager* mgr,
-			s32 id=-1, u32 boneIndex=0, const c8* boneName=0);
+			s32 id=-1, u32 boneIndex=0,
+			const std::optional<std::string> &boneName = std::nullopt);
 
 		//! Returns the index of the bone
 		u32 getBoneIndex() const override;
diff --git a/source/Irrlicht/CSceneManager.cpp b/source/Irrlicht/CSceneManager.cpp
index c90ec33..71c8b86 100644
--- a/source/Irrlicht/CSceneManager.cpp
+++ b/source/Irrlicht/CSceneManager.cpp
@@ -697,7 +697,8 @@ ISceneNode* CSceneManager::getSceneNodeFromName(const char* name, ISceneNode* st
 	if (start == 0)
 		start = getRootSceneNode();
 
-	if (!strcmp(start->getName(),name))
+	auto startName = start->getName();
+	if (startName.has_value() && startName == name)
 		return start;
 
 	ISceneNode* node = 0;
diff --git a/source/Irrlicht/CSkinnedMesh.cpp b/source/Irrlicht/CSkinnedMesh.cpp
index 08cffe7..c36a285 100644
--- a/source/Irrlicht/CSkinnedMesh.cpp
+++ b/source/Irrlicht/CSkinnedMesh.cpp
@@ -3,6 +3,7 @@
 // For conditions of distribution and use, see copyright notice in irrlicht.h
 
 #include "CSkinnedMesh.h"
+#include <optional>
 #include "CBoneSceneNode.h"
 #include "IAnimatedMeshSceneNode.h"
 #include "os.h"
@@ -624,18 +625,18 @@ u32 CSkinnedMesh::getJointCount() const
 	return AllJoints.size();
 }
 
-
 //! Gets the name of a joint.
-const c8* CSkinnedMesh::getJointName(u32 number) const
-{
-	if (number >= AllJoints.size())
-		return 0;
-	return AllJoints[number]->Name.c_str();
+const std::optional<std::string> &CSkinnedMesh::getJointName(u32 number) const {
+	if (number >= getJointCount()) {
+		static const std::optional<std::string> nullopt;
+		return nullopt;
+	}
+	return AllJoints[number]->Name;
 }
 
 
 //! Gets a joint number from its name
-s32 CSkinnedMesh::getJointNumber(const c8* name) const
+std::optional<u32> CSkinnedMesh::getJointNumber(const std::string &name) const
 {
 	for (u32 i=0; i<AllJoints.size(); ++i)
 	{
@@ -643,7 +644,7 @@ s32 CSkinnedMesh::getJointNumber(const c8* name) const
 			return i;
 	}
 
-	return -1;
+	return std::nullopt;
 }
 
 
@@ -1396,7 +1397,7 @@ void CSkinnedMesh::addJoints(core::array<IBoneSceneNode*> &jointChildSceneNodes,
 	//Create new joints
 	for (u32 i=0; i<AllJoints.size(); ++i)
 	{
-		jointChildSceneNodes.push_back(new CBoneSceneNode(0, smgr, 0, i, AllJoints[i]->Name.c_str()));
+		jointChildSceneNodes.push_back(new CBoneSceneNode(0, smgr, 0, i, AllJoints[i]->Name));
 	}
 
 	//Match up parents
diff --git a/source/Irrlicht/CSkinnedMesh.h b/source/Irrlicht/CSkinnedMesh.h
index d31cd6f..cc119ad 100644
--- a/source/Irrlicht/CSkinnedMesh.h
+++ b/source/Irrlicht/CSkinnedMesh.h
@@ -8,9 +8,6 @@
 
 #include "ISkinnedMesh.h"
 #include "SMeshBuffer.h"
-#include "S3DVertex.h"
-#include "irrString.h"
-#include "matrix4.h"
 #include "quaternion.h"
 
 namespace irr
@@ -84,10 +81,10 @@ namespace scene
 		u32 getJointCount() const override;
 
 		//! Gets the name of a joint.
-		const c8* getJointName(u32 number) const override;
+		const std::optional<std::string> &getJointName(u32 number) const override;
 
 		//! Gets a joint number from its name
-		s32 getJointNumber(const c8* name) const override;
+		std::optional<u32> getJointNumber(const std::string &name) const override;
 
 		//! uses animation from another mesh
 		bool useAnimationFrom(const ISkinnedMesh *mesh) override;
diff --git a/source/Irrlicht/CXMeshFileLoader.cpp b/source/Irrlicht/CXMeshFileLoader.cpp
index cdcd7a8..403c595 100644
--- a/source/Irrlicht/CXMeshFileLoader.cpp
+++ b/source/Irrlicht/CXMeshFileLoader.cpp
@@ -594,16 +594,11 @@ bool CXMeshFileLoader::parseDataObjectFrame(CSkinnedMesh::SJoint *Parent)
 
 	CSkinnedMesh::SJoint *joint=0;
 
-	if (name.size())
-	{
-		for (u32 n=0; n < AnimatedMesh->getAllJoints().size(); ++n)
-		{
-			if (AnimatedMesh->getAllJoints()[n]->Name==name)
-			{
-				joint=AnimatedMesh->getAllJoints()[n];
-				JointID=n;
-				break;
-			}
+	if (name.size()) {
+		auto n = AnimatedMesh->getJointNumber(name.c_str());
+		if (n.has_value()) {
+			JointID = *n;
+			joint = AnimatedMesh->getAllJoints()[JointID];
 		}
 	}
 
@@ -613,7 +608,7 @@ bool CXMeshFileLoader::parseDataObjectFrame(CSkinnedMesh::SJoint *Parent)
 		os::Printer::log("creating joint ", name.c_str(), ELL_DEBUG);
 #endif
 		joint=AnimatedMesh->addJoint(Parent);
-		joint->Name=name;
+		joint->Name=name.c_str();
 		JointID=AnimatedMesh->getAllJoints().size()-1;
 	}
 	else
@@ -1121,17 +1116,8 @@ bool CXMeshFileLoader::parseDataObjectSkinWeights(SXMesh &mesh)
 
 	mesh.HasSkinning=true;
 
-	CSkinnedMesh::SJoint *joint=0;
-
-	u32 n;
-	for (n=0; n < AnimatedMesh->getAllJoints().size(); ++n)
-	{
-		if (AnimatedMesh->getAllJoints()[n]->Name==TransformNodeName)
-		{
-			joint=AnimatedMesh->getAllJoints()[n];
-			break;
-		}
-	}
+	auto n = AnimatedMesh->getJointNumber(TransformNodeName.c_str());
+	CSkinnedMesh::SJoint *joint = n.has_value() ? AnimatedMesh->getAllJoints()[*n] : nullptr;
 
 	if (!joint)
 	{
@@ -1140,7 +1126,7 @@ bool CXMeshFileLoader::parseDataObjectSkinWeights(SXMesh &mesh)
 #endif
 		n = AnimatedMesh->getAllJoints().size();
 		joint=AnimatedMesh->addJoint(0);
-		joint->Name=TransformNodeName;
+		joint->Name=TransformNodeName.c_str();
 	}
 
 	// read vertex weights
@@ -1157,7 +1143,7 @@ bool CXMeshFileLoader::parseDataObjectSkinWeights(SXMesh &mesh)
 
 	for (i=0; i<nWeights; ++i)
 	{
-		mesh.WeightJoint.push_back(n);
+		mesh.WeightJoint.push_back(*n);
 		mesh.WeightNum.push_back(joint->Weights.size());
 
 		CSkinnedMesh::SWeight *weight=AnimatedMesh->addWeight(joint);
@@ -1668,41 +1654,33 @@ bool CXMeshFileLoader::parseDataObjectAnimation()
 #ifdef _XREADER_DEBUG
 		os::Printer::log("frame name", FrameName.c_str(), ELL_DEBUG);
 #endif
-		CSkinnedMesh::SJoint *joint=0;
+		auto n = AnimatedMesh->getJointNumber(FrameName.c_str());
 
-		u32 n;
-		for (n=0; n < AnimatedMesh->getAllJoints().size(); ++n)
-		{
-			if (AnimatedMesh->getAllJoints()[n]->Name==FrameName)
-			{
-				joint=AnimatedMesh->getAllJoints()[n];
-				break;
-			}
-		}
-
-		if (!joint)
-		{
+		CSkinnedMesh::SJoint *joint;
+		if (n.has_value()) {
+			joint = AnimatedMesh->getAllJoints()[*n];
+		} else {
 #ifdef _XREADER_DEBUG
 			os::Printer::log("creating joint for animation ", FrameName.c_str(), ELL_DEBUG);
 #endif
 			joint=AnimatedMesh->addJoint(0);
-			joint->Name=FrameName;
+			joint->Name=FrameName.c_str();
 		}
 
 		joint->PositionKeys.reallocate(joint->PositionKeys.size()+animationDump.PositionKeys.size());
-		for (n=0; n<animationDump.PositionKeys.size(); ++n)
+		for (u32 n=0; n<animationDump.PositionKeys.size(); ++n)
 		{
 			joint->PositionKeys.push_back(animationDump.PositionKeys[n]);
 		}
 
 		joint->ScaleKeys.reallocate(joint->ScaleKeys.size()+animationDump.ScaleKeys.size());
-		for (n=0; n<animationDump.ScaleKeys.size(); ++n)
+		for (u32 n=0; n<animationDump.ScaleKeys.size(); ++n)
 		{
 			joint->ScaleKeys.push_back(animationDump.ScaleKeys[n]);
 		}
 
 		joint->RotationKeys.reallocate(joint->RotationKeys.size()+animationDump.RotationKeys.size());
-		for (n=0; n<animationDump.RotationKeys.size(); ++n)
+		for (u32 n=0; n<animationDump.RotationKeys.size(); ++n)
 		{
 			joint->RotationKeys.push_back(animationDump.RotationKeys[n]);
 		}
diff --git a/source/Irrlicht/SB3DStructs.h b/source/Irrlicht/SB3DStructs.h
index c2d2bda..264b475 100644
--- a/source/Irrlicht/SB3DStructs.h
+++ b/source/Irrlicht/SB3DStructs.h
@@ -39,7 +39,7 @@ struct SB3dChunk
 
 struct SB3dTexture
 {
-	core::stringc TextureName;
+	std::string TextureName;
 	s32 Flags;
 	s32 Blend;
 	f32 Xpos;