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std::vector<std::shared_ptr<Mesh>> GameObject::LoadModel(ID3D12Device* device, ID3D12GraphicsCommandList* cmdList, const std::wstring& path,const bool& makeRigidbody){std::ifstream in_file{ path, std::ios::binary };assert(in_file.is_open(), L"No such file in path [" + path + L"]");std::vector<XMFLOAT3> positions;std::vector<XMFLOAT3> normals;std::vector<XMFLOAT2> texcoords;std::unordered_map<std::string, MatInfo> mats;std::shared_ptr<Mesh> new_mesh;std::string info;while (std::getline(in_file, info)){std::stringstream ss(info);std::string type;ss >> type;if (type == "mtllib"){std::string mtlname;ss >> mtlname;std::wstring mtl_path = L"";std::wstring::size_type n = path.find('\\');if (n != std::wstring::npos)mtl_path = path.substr(0, n + 1);mtl_path += std::wstring(mtlname.begin(), mtlname.end());LoadMaterial(device, cmdList, mats, mtl_path);}else if (type == "v"){XMFLOAT3 pos;ss >> pos.x >> pos.y >> pos.z;pos.z *= -1.0f;positions.push_back(pos);}else if (type == "vt"){XMFLOAT2 tex;ss >> tex.x >> tex.y;//tex.y = 1.0f - tex.y;texcoords.push_back(tex);}else if (type == "vn"){XMFLOAT3 norm;ss >> norm.x >> norm.y >> norm.z;norm.z *= -1.0f;normals.push_back(norm);}else if (type == "usemtl"){std::string mtl_name;ss >> mtl_name;new_mesh = std::make_shared<Mesh>(mtl_name);new_mesh->LoadMesh(device, cmdList, in_file, positions, normals, texcoords, mats[mtl_name], makeRigidbody);mMeshes.push_back(new_mesh);}}const auto& [min_x, max_x] = std::minmax_element(positions.begin(), positions.end(), [](const XMFLOAT3& a, const XMFLOAT3& b) { return (a.x < b.x); });const auto& [min_y, max_y] = std::minmax_element(positions.begin(), positions.end(),[](const XMFLOAT3& a, const XMFLOAT3& b) {return (a.y < b.y); });const auto& [min_z, max_z] = std::minmax_element(positions.begin(), positions.end(),[](const XMFLOAT3& a, const XMFLOAT3& b) {return (a.z < b.z); });mOOBB.Center = { (min_x->x + max_x->x) / 2, (min_y->y + max_y->y) / 2, (min_z->z + max_z->z) / 2 };mOOBB.Extents = { (max_x->x - min_x->x) / 2, (max_y->y - min_y->y) / 2, (max_z->z - min_z->z) / 2 };return mMeshes;}void Mesh::LoadMesh(ID3D12Device* device, ID3D12GraphicsCommandList* cmdList,std::ifstream& file,const std::vector<XMFLOAT3>& positions,const std::vector<XMFLOAT3>& normals,const std::vector<XMFLOAT2>& texcoords,const MatInfo& mat,const bool& makeRigidbody){mMaterial = mat;struct UINT3{UINT vertIndex;UINT normIndex;UINT texIndex;};std::vector<std::vector<UINT3>> temp_indices;int last_pos = 0;std::string info;while (std::getline(file, info)){std::stringstream ss(info);std::string type;ss >> type;if (type == "f"){char ignore[2];UINT v, vt, vn;temp_indices.push_back({});while (ss >> v >> ignore[0] >> vt >> ignore[1] >> vn){temp_indices.back().push_back({ v - 1, vn - 1, vt - 1 });}last_pos = (int)file.tellg();}else if (type == "usemtl") {file.seekg(last_pos);break;}}std::vector<Vertex> vertices;std::vector<UINT> indices;UINT k = 0;for (const std::vector<UINT3>& curr_face : temp_indices){for (int i = 0; i < curr_face.size(); i++){Vertex v;v.Position = positions[curr_face[i].vertIndex];v.Normal = normals[curr_face[i].normIndex];v.TexCoord = texcoords[curr_face[i].texIndex];v.TexCoord.x /= mat.TexScale.x;v.TexCoord.x += mat.TexOffset.x;v.TexCoord.y /= mat.TexScale.y;v.TexCoord.y += mat.TexOffset.y;v.TexCoord.y = 1.0f - v.TexCoord.y;vertices.push_back(v);if (i > 0 && indices.size() % 3 == 0){indices.push_back(*(indices.end() - 3));indices.push_back(*(indices.end() - 2));}indices.push_back(k++);}}const auto& [min_x, max_x] = std::minmax_element(positions.begin(), positions.end(),[](const XMFLOAT3& a, const XMFLOAT3& b) { return (a.x < b.x); });const auto& [min_y, max_y] = std::minmax_element(positions.begin(), positions.end(),[](const XMFLOAT3& a, const XMFLOAT3& b) {return (a.y < b.y); });const auto& [min_z, max_z] = std::minmax_element(positions.begin(), positions.end(),[](const XMFLOAT3& a, const XMFLOAT3& b) {return (a.z < b.z); });mOOBB.Center = { (min_x->x + max_x->x) / 2, (min_y->y + max_y->y) / 2, (min_z->z + max_z->z) / 2 };mOOBB.Extents = { (max_x->x - min_x->x) / 2, (max_y->y - min_y->y) / 2, (max_z->z - min_z->z) / 2 };if(makeRigidbody)CreateRigidBody(vertices, indices);std::reverse(indices.begin(), indices.end());Mesh::CreateResourceInfo(device, cmdList, sizeof(Vertex), sizeof(UINT),D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST,vertices.data(), (UINT)vertices.size(), indices.data(), (UINT)indices.size());}void Mesh::CreateRigidBody(const std::vector<Vertex>& targetVertices, const std::vector<UINT>& targetIndices){mTriangleVertexArray = new btTriangleIndexVertexArray();btIndexedMesh tempMesh;mTriangleVertexArray->addIndexedMesh(tempMesh, PHY_FLOAT);btIndexedMesh& mesh = mTriangleVertexArray->getIndexedMeshArray()[0];const int32_t VERTICES_PER_TRIANGLE = 3;size_t numIndices = targetIndices.size();mesh.m_numTriangles = numIndices / VERTICES_PER_TRIANGLE;if (numIndices < std::numeric_limits<int16_t>::max()){mesh.m_triangleIndexBase = new unsigned char[sizeof(int16_t) * (size_t)numIndices];mesh.m_indexType = PHY_SHORT;mesh.m_triangleIndexStride = VERTICES_PER_TRIANGLE * sizeof(int16_t);}else{mesh.m_triangleIndexBase = new unsigned char[sizeof(int32_t) * (size_t)numIndices];mesh.m_indexType = PHY_INTEGER;mesh.m_triangleIndexStride = VERTICES_PER_TRIANGLE * sizeof(int32_t);}mesh.m_numVertices = targetVertices.size();mesh.m_vertexBase = new unsigned char[VERTICES_PER_TRIANGLE * sizeof(btScalar) * (size_t)mesh.m_numVertices];mesh.m_vertexStride = VERTICES_PER_TRIANGLE * sizeof(btScalar);btScalar* vertexData = static_cast<btScalar*>((void*)(mesh.m_vertexBase));for (int32_t i = 0; i < mesh.m_numVertices; ++i){int32_t j = i * VERTICES_PER_TRIANGLE;const XMFLOAT3& point = targetVertices[i].Position;vertexData[j] = point.x;vertexData[j + 1] = point.y;vertexData[j + 2] = point.z;}if (numIndices < std::numeric_limits<int16_t>::max()){int16_t* indices = static_cast<int16_t*>((void*)(mesh.m_triangleIndexBase));for (int32_t i = 0; i < numIndices; ++i) {indices[i] = (int16_t)targetIndices[i];}}else{int32_t* indices = static_cast<int32_t*>((void*)(mesh.m_triangleIndexBase));for (int32_t i = 0; i < numIndices; ++i){indices[i] = targetIndices[i];}}const bool USE_QUANTIZED_AABB_COMPRESSION = true;mMeshShape = std::make_shared<btBvhTriangleMeshShape>(mTriangleVertexArray, USE_QUANTIZED_AABB_COMPRESSION);}void PhysicsPlayer::BuildRigidBody(std::shared_ptr<BulletWrapper> physics){auto dynamicsWorld = physics->GetDynamicsWorld();mOOBB.Extents = { 10.0f, 4.0f, 14.0f }; // this value is for wheelXMFLOAT3 vehicleExtents = mOOBB.Extents;XMFLOAT3 wheelExtents = mWheel[0]->GetBoundingBox().Extents;btCompoundShape* chassisShape = new btCompoundShape();for (int i = 0; i < mMeshes.size(); ++i){btTransform LocalTransform;LocalTransform.setIdentity();LocalTransform.setOrigin(btVector3(0, 0, 0));chassisShape->addChildShape(LocalTransform, mMeshes[i]->GetMeshShape().get());}btTransform btCarTransform;btCarTransform.setIdentity();btCarTransform.setOrigin(btVector3(mPosition.x, mPosition.y, mPosition.z));mBtRigidBody = physics->CreateRigidBody(1000.0f, btCarTransform, chassisShape);mVehicleRayCaster = std::make_shared<btDefaultVehicleRaycaster>(dynamicsWorld.get());mVehicle = std::make_shared<btRaycastVehicle>(mTuning, mBtRigidBody, mVehicleRayCaster.get());mBtRigidBody->setActivationState(DISABLE_DEACTIVATION);dynamicsWorld->addVehicle(mVehicle.get());mVehicle->setCoordinateSystem(0, 1, 2);btVector3 wheelDirectionCS0(0, -1, 0);btVector3 wheelAxleCS(-1, 0, 0);float wheelWidth = wheelExtents.x;float wheelRadius = wheelExtents.z;float wheelFriction = 26.0f;float suspensionStiffness = 20.f;float suspensionDamping = 2.3f;float suspensionCompression = 4.4f;float rollInfluence = 0.01f;  //1.0f;bool isFrontWheel = true;float connectionHeight = -0.9f;btVector3 connectionPointCS0(vehicleExtents.x - 2.5f, connectionHeight, vehicleExtents.z - 2.8f);mVehicle->addWheel(connectionPointCS0, wheelDirectionCS0, wheelAxleCS, 0.6, wheelRadius, mTuning, isFrontWheel);connectionPointCS0 = btVector3(-vehicleExtents.x + 2.5f, connectionHeight, vehicleExtents.z - 2.8f);mVehicle->addWheel(connectionPointCS0, wheelDirectionCS0, wheelAxleCS, 0.6, wheelRadius, mTuning, isFrontWheel);isFrontWheel = false;connectionPointCS0 = btVector3(vehicleExtents.x - 2.3f, connectionHeight, -vehicleExtents.z + 2.6f);mVehicle->addWheel(connectionPointCS0, wheelDirectionCS0, wheelAxleCS, 0.6, wheelRadius, mTuning, isFrontWheel);connectionPointCS0 = btVector3(-vehicleExtents.x + 2.3f, connectionHeight, -vehicleExtents.z + 2.6f);mVehicle->addWheel(connectionPointCS0, wheelDirectionCS0, wheelAxleCS, 0.6, wheelRadius, mTuning, isFrontWheel);for (int i = 0; i < mVehicle->getNumWheels(); i++){btWheelInfo& wheel = mVehicle->getWheelInfo(i);wheel.m_suspensionStiffness = suspensionStiffness;wheel.m_wheelsDampingRelaxation = suspensionDamping;wheel.m_wheelsDampingCompression = suspensionCompression;wheel.m_frictionSlip = wheelFriction;wheel.m_rollInfluence = rollInfluence;}}btRigidBody* BulletWrapper::CreateRigidBody(btScalar mass, const btTransform& startTransform, btCollisionShape* shape){btAssert((!shape || shape->getShapeType() != INVALID_SHAPE_PROXYTYPE));bool isDynamic = (mass != 0.f);btVector3 localInertia(0, 0, 0);if (isDynamic)shape->calculateLocalInertia(mass, localInertia);btDefaultMotionState* myMotionState = new btDefaultMotionState(startTransform);btRigidBody::btRigidBodyConstructionInfo cInfo(mass, myMotionState, shape, localInertia);btRigidBody* body = new btRigidBody(cInfo);mBtDynamicsWorld->addRigidBody(body);AddShape(shape);return body;}