.. AUTOGENERATE: DO NOT EDIT .. _Virtualfilesystem: Virtual file system ^^^^^^^^^^^^^^^^^^^ Virtual file system (VFS) functionality was introduced in MuJoCo 1.50. It enables the user to load all necessary files in memory, including MJB binary model files, XML files (MJCF, URDF and included files), STL meshes, PNGs for textures and height fields, and HF files in our custom height field format. Model and resource files in the VFS can also be constructed programmatically (say using a Python library that writes to memory). Once all desired files are in the VFS, the user can call :ref:`mj_loadModel` or :ref:`mj_loadXML` with a pointer to the VFS. When this pointer is not NULL, the loaders will first check the VFS for any file they are about to load, and only access the disk if the file is not found in the VFS. The file names stored in the VFS have their name and extension but the path information is stripped; this can be bypassed however by using a custom path symbol in the file names, say "mydir_myfile.xml". The entire VFS is contained in the data structure :ref:`mjVFS`. All utility functions for maintaining the VFS operate on this data structure. The common usage pattern is to first clear it with mj_defaultVFS, then add disk files to it with mj_addFileVFS (which allocates memory buffers and loads the file content in memory), then call mj_loadXML or mj_loadModel, and then clear everything with mj_deleteVFS. .. _mj_defaultVFS: mj_defaultVFS ~~~~~~~~~~~~~ .. mujoco-include:: mj_defaultVFS Initialize VFS to empty (no deallocation). .. _mj_addFileVFS: mj_addFileVFS ~~~~~~~~~~~~~ .. mujoco-include:: mj_addFileVFS Add file to VFS, return 0: success, 1: full, 2: repeated name, -1: failed to load. .. _mj_makeEmptyFileVFS: mj_makeEmptyFileVFS ~~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_makeEmptyFileVFS Make empty file in VFS, return 0: success, 1: full, 2: repeated name. .. _mj_findFileVFS: mj_findFileVFS ~~~~~~~~~~~~~~ .. mujoco-include:: mj_findFileVFS Return file index in VFS, or -1 if not found in VFS. .. _mj_deleteFileVFS: mj_deleteFileVFS ~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_deleteFileVFS Delete file from VFS, return 0: success, -1: not found in VFS. .. _mj_deleteVFS: mj_deleteVFS ~~~~~~~~~~~~ .. mujoco-include:: mj_deleteVFS Delete all files from VFS. .. _Parseandcompile: Parse and compile ^^^^^^^^^^^^^^^^^ The key function here is mj_loadXML. It invokes the built-in parser and compiler, and either returns a pointer to a valid mjModel, or NULL - in which case the user should check the error information in the user-provided string. The model and all files referenced in it can be loaded from disk or from a VFS when provided. .. _mj_loadXML: mj_loadXML ~~~~~~~~~~ .. mujoco-include:: mj_loadXML Parse XML file in MJCF or URDF format, compile it, return low-level model. If vfs is not ``NULL``, look up files in vfs before reading from disk. If error is not ``NULL``, it must have size error_sz. .. _mj_saveLastXML: mj_saveLastXML ~~~~~~~~~~~~~~ .. mujoco-include:: mj_saveLastXML Update XML data structures with info from low-level model, save as MJCF. If error is not ``NULL``, it must have size error_sz. .. _mj_freeLastXML: mj_freeLastXML ~~~~~~~~~~~~~~ .. mujoco-include:: mj_freeLastXML Free last XML model if loaded. Called internally at each load. .. _mj_printSchema: mj_printSchema ~~~~~~~~~~~~~~ .. mujoco-include:: mj_printSchema Print internal XML schema as plain text or HTML, with style-padding or `` ``. .. _Mainsimulation: Main simulation ^^^^^^^^^^^^^^^ These are the main entry points to the simulator. Most users will only need to call ``mj_step``, which computes everything and advanced the simulation state by one time step. Controls and applied forces must either be set in advance (in mjData.ctrl, qfrc_applied and xfrc_applied), or a control callback mjcb_control must be installed which will be called just before the controls and applied forces are needed. Alternatively, one can use ``mj_step1`` and ``mj_step2`` which break down the simulation pipeline into computations that are executed before and after the controls are needed; in this way one can set controls that depend on the results from ``mj_step1``. Keep in mind though that the RK4 solver does not work with mj_step1/2. mj_forward performs the same computations as ``mj_step`` but without the integration. It is useful after loading or resetting a model (to put the entire mjData in a valid state), and also for out-of-order computations that involve sampling or finite-difference approximations. mj_inverse runs the inverse dynamics, and writes its output in mjData.qfrc_inverse. Note that mjData.qacc must be set before calling this function. Given the state (qpos, qvel, act), mj_forward maps from force to acceleration, while mj_inverse maps from acceleration to force. Mathematically these functions are inverse of each other, but numerically this may not always be the case because the forward dynamics rely on a constraint optimization algorithm which is usually terminated early. The difference between the results of forward and inverse dynamics can be computed with the function :ref:`mj_compareFwdInv`, which can be though of as another solver accuracy check (as well as a general sanity check). The skip version of mj_forward and mj_inverse are useful for example when qpos was unchanged but qvel was changed (usually in the context of finite differencing). Then there is no point repeating the computations that only depend on qpos. Calling the dynamics with skipstage = mjSTAGE_POS will achieve these savings. .. _mj_step: mj_step ~~~~~~~ .. mujoco-include:: mj_step Advance simulation, use control callback to obtain external force and control. .. _mj_step1: mj_step1 ~~~~~~~~ .. mujoco-include:: mj_step1 Advance simulation in two steps: before external force and control is set by user. .. _mj_step2: mj_step2 ~~~~~~~~ .. mujoco-include:: mj_step2 Advance simulation in two steps: after external force and control is set by user. .. _mj_forward: mj_forward ~~~~~~~~~~ .. mujoco-include:: mj_forward Forward dynamics: same as mj_step but do not integrate in time. .. _mj_inverse: mj_inverse ~~~~~~~~~~ .. mujoco-include:: mj_inverse Inverse dynamics: qacc must be set before calling. .. _mj_forwardSkip: mj_forwardSkip ~~~~~~~~~~~~~~ .. mujoco-include:: mj_forwardSkip Forward dynamics with skip; skipstage is mjtStage. .. _mj_inverseSkip: mj_inverseSkip ~~~~~~~~~~~~~~ .. mujoco-include:: mj_inverseSkip Inverse dynamics with skip; skipstage is mjtStage. .. _Initialization: Initialization ^^^^^^^^^^^^^^ This section contains functions that load/initialize the model or other data structures. Their use is well illustrated in the code samples. .. _mj_defaultLROpt: mj_defaultLROpt ~~~~~~~~~~~~~~~ .. mujoco-include:: mj_defaultLROpt Set default options for length range computation. .. _mj_defaultSolRefImp: mj_defaultSolRefImp ~~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_defaultSolRefImp Set solver parameters to default values. .. _mj_defaultOption: mj_defaultOption ~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_defaultOption Set physics options to default values. .. _mj_defaultVisual: mj_defaultVisual ~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_defaultVisual Set visual options to default values. .. _mj_copyModel: mj_copyModel ~~~~~~~~~~~~ .. mujoco-include:: mj_copyModel Copy ``mjModel``, allocate new if dest is ``NULL``. .. _mj_saveModel: mj_saveModel ~~~~~~~~~~~~ .. mujoco-include:: mj_saveModel Save model to binary MJB file or memory buffer; buffer has precedence when given. .. _mj_loadModel: mj_loadModel ~~~~~~~~~~~~ .. mujoco-include:: mj_loadModel Load model from binary MJB file. If vfs is not ``NULL``, look up file in vfs before reading from disk. .. _mj_deleteModel: mj_deleteModel ~~~~~~~~~~~~~~ .. mujoco-include:: mj_deleteModel Free memory allocation in model. .. _mj_sizeModel: mj_sizeModel ~~~~~~~~~~~~ .. mujoco-include:: mj_sizeModel Return size of buffer needed to hold model. .. _mj_makeData: mj_makeData ~~~~~~~~~~~ .. mujoco-include:: mj_makeData Allocate ``mjData`` corresponding to given model. If the model buffer is unallocated the initial configuration will not be set. .. _mj_copyData: mj_copyData ~~~~~~~~~~~ .. mujoco-include:: mj_copyData Copy ``mjData``. m is only required to contain the size fields from MJMODEL_INTS. .. _mj_resetData: mj_resetData ~~~~~~~~~~~~ .. mujoco-include:: mj_resetData Reset data to defaults. .. _mj_resetDataDebug: mj_resetDataDebug ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_resetDataDebug Reset data to defaults, fill everything else with debug_value. .. _mj_resetDataKeyframe: mj_resetDataKeyframe ~~~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_resetDataKeyframe Reset data, set fields from specified keyframe. .. _mj_stackAlloc: mj_stackAlloc ~~~~~~~~~~~~~ .. mujoco-include:: mj_stackAlloc Allocate array of specified size on ``mjData`` stack. Call mju_error on stack overflow. .. _mj_deleteData: mj_deleteData ~~~~~~~~~~~~~ .. mujoco-include:: mj_deleteData Free memory allocation in ``mjData``. .. _mj_resetCallbacks: mj_resetCallbacks ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_resetCallbacks Reset all callbacks to ``NULL`` pointers (``NULL`` is the default). .. _mj_setConst: mj_setConst ~~~~~~~~~~~ .. mujoco-include:: mj_setConst Set constant fields of ``mjModel``, corresponding to qpos0 configuration. .. _mj_setLengthRange: mj_setLengthRange ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_setLengthRange Set actuator_lengthrange for specified actuator; return 1 if ok, 0 if error. .. _Printing: Printing ^^^^^^^^ These functions can be used to print various quantities to the screen for debugging purposes. .. _mj_printFormattedModel: mj_printFormattedModel ~~~~~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_printFormattedModel Print ``mjModel`` to text file, specifying format. float_format must be a valid printf-style format string for a single float value. .. _mj_printModel: mj_printModel ~~~~~~~~~~~~~ .. mujoco-include:: mj_printModel Print model to text file. .. _mj_printFormattedData: mj_printFormattedData ~~~~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_printFormattedData Print ``mjData`` to text file, specifying format. float_format must be a valid printf-style format string for a single float value .. _mj_printData: mj_printData ~~~~~~~~~~~~ .. mujoco-include:: mj_printData Print data to text file. .. _mju_printMat: mju_printMat ~~~~~~~~~~~~ .. mujoco-include:: mju_printMat Print matrix to screen. .. _mju_printMatSparse: mju_printMatSparse ~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mju_printMatSparse Print sparse matrix to screen. .. _Components: Components ^^^^^^^^^^ These are components of the simulation pipeline, called internally from mj_step, mj_forward and mj_inverse. It is unlikely that the user will need to call them. .. _mj_fwdPosition: mj_fwdPosition ~~~~~~~~~~~~~~ .. mujoco-include:: mj_fwdPosition Run position-dependent computations. .. _mj_fwdVelocity: mj_fwdVelocity ~~~~~~~~~~~~~~ .. mujoco-include:: mj_fwdVelocity Run velocity-dependent computations. .. _mj_fwdActuation: mj_fwdActuation ~~~~~~~~~~~~~~~ .. mujoco-include:: mj_fwdActuation Compute actuator force qfrc_actuator. .. _mj_fwdAcceleration: mj_fwdAcceleration ~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_fwdAcceleration Add up all non-constraint forces, compute qacc_smooth. .. _mj_fwdConstraint: mj_fwdConstraint ~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_fwdConstraint Run selected constraint solver. .. _mj_Euler: mj_Euler ~~~~~~~~ .. mujoco-include:: mj_Euler Euler integrator, semi-implicit in velocity. .. _mj_RungeKutta: mj_RungeKutta ~~~~~~~~~~~~~ .. mujoco-include:: mj_RungeKutta Runge-Kutta explicit order-N integrator. .. _mj_invPosition: mj_invPosition ~~~~~~~~~~~~~~ .. mujoco-include:: mj_invPosition Run position-dependent computations in inverse dynamics. .. _mj_invVelocity: mj_invVelocity ~~~~~~~~~~~~~~ .. mujoco-include:: mj_invVelocity Run velocity-dependent computations in inverse dynamics. .. _mj_invConstraint: mj_invConstraint ~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_invConstraint Apply the analytical formula for inverse constraint dynamics. .. _mj_compareFwdInv: mj_compareFwdInv ~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_compareFwdInv Compare forward and inverse dynamics, save results in fwdinv. .. _Subcomponents: Sub components ^^^^^^^^^^^^^^ These are sub-components of the simulation pipeline, called internally from the components above. It is very unlikely that the user will need to call them. .. _mj_sensorPos: mj_sensorPos ~~~~~~~~~~~~ .. mujoco-include:: mj_sensorPos Evaluate position-dependent sensors. .. _mj_sensorVel: mj_sensorVel ~~~~~~~~~~~~ .. mujoco-include:: mj_sensorVel Evaluate velocity-dependent sensors. .. _mj_sensorAcc: mj_sensorAcc ~~~~~~~~~~~~ .. mujoco-include:: mj_sensorAcc Evaluate acceleration and force-dependent sensors. .. _mj_energyPos: mj_energyPos ~~~~~~~~~~~~ .. mujoco-include:: mj_energyPos Evaluate position-dependent energy (potential). .. _mj_energyVel: mj_energyVel ~~~~~~~~~~~~ .. mujoco-include:: mj_energyVel Evaluate velocity-dependent energy (kinetic). .. _mj_checkPos: mj_checkPos ~~~~~~~~~~~ .. mujoco-include:: mj_checkPos Check qpos, reset if any element is too big or nan. .. _mj_checkVel: mj_checkVel ~~~~~~~~~~~ .. mujoco-include:: mj_checkVel Check qvel, reset if any element is too big or nan. .. _mj_checkAcc: mj_checkAcc ~~~~~~~~~~~ .. mujoco-include:: mj_checkAcc Check qacc, reset if any element is too big or nan. .. _mj_kinematics: mj_kinematics ~~~~~~~~~~~~~ .. mujoco-include:: mj_kinematics Run forward kinematics. .. _mj_comPos: mj_comPos ~~~~~~~~~ .. mujoco-include:: mj_comPos Map inertias and motion dofs to global frame centered at CoM. .. _mj_camlight: mj_camlight ~~~~~~~~~~~ .. mujoco-include:: mj_camlight Compute camera and light positions and orientations. .. _mj_tendon: mj_tendon ~~~~~~~~~ .. mujoco-include:: mj_tendon Compute tendon lengths, velocities and moment arms. .. _mj_transmission: mj_transmission ~~~~~~~~~~~~~~~ .. mujoco-include:: mj_transmission Compute actuator transmission lengths and moments. .. _mj_crb: mj_crb ~~~~~~ .. mujoco-include:: mj_crb Run composite rigid body inertia algorithm (CRB). .. _mj_factorM: mj_factorM ~~~~~~~~~~ .. mujoco-include:: mj_factorM Compute sparse :math:`L^T D L` factorizaton of inertia matrix. .. _mj_solveM: mj_solveM ~~~~~~~~~ .. mujoco-include:: mj_solveM Solve linear system :math:`M x = y` using factorization: :math:`x = (L^T D L)^{-1} y` .. _mj_solveM2: mj_solveM2 ~~~~~~~~~~ .. mujoco-include:: mj_solveM2 Half of linear solve: :math:`x = \sqrt{D^{-1}} (L^T)^{-1} y` .. _mj_comVel: mj_comVel ~~~~~~~~~ .. mujoco-include:: mj_comVel Compute cvel, cdof_dot. .. _mj_passive: mj_passive ~~~~~~~~~~ .. mujoco-include:: mj_passive Compute qfrc_passive from spring-dampers, viscosity and density. .. _mj_subtreeVel: mj_subtreeVel ~~~~~~~~~~~~~ .. mujoco-include:: mj_subtreeVel subtree linear velocity and angular momentum .. _mj_rne: mj_rne ~~~~~~ .. mujoco-include:: mj_rne RNE: compute M(qpos)*qacc + C(qpos,qvel); flg_acc=0 removes inertial term. .. _mj_rnePostConstraint: mj_rnePostConstraint ~~~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_rnePostConstraint RNE with complete data: compute cacc, cfrc_ext, cfrc_int. .. _mj_collision: mj_collision ~~~~~~~~~~~~ .. mujoco-include:: mj_collision Run collision detection. .. _mj_makeConstraint: mj_makeConstraint ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_makeConstraint Construct constraints. .. _mj_projectConstraint: mj_projectConstraint ~~~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_projectConstraint Compute inverse constraint inertia efc_AR. .. _mj_referenceConstraint: mj_referenceConstraint ~~~~~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_referenceConstraint Compute efc_vel, efc_aref. .. _mj_constraintUpdate: mj_constraintUpdate ~~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_constraintUpdate Compute efc_state, efc_force, qfrc_constraint, and (optionally) cone Hessians. If cost is not ``NULL``, set \*cost = s(jar) where jar = Jac*qacc-aref. .. _Support: Support ^^^^^^^ These are support functions that need access to mjModel and mjData, unlike the utility functions which do not need such access. Support functions are called within the simulator but some of them can also be useful for custom computations, and are documented in more detail below. .. _mj_addContact: mj_addContact ~~~~~~~~~~~~~ .. mujoco-include:: mj_addContact Add contact to d->contact list; return 0 if success; 1 if buffer full. .. _mj_isPyramidal: mj_isPyramidal ~~~~~~~~~~~~~~ .. mujoco-include:: mj_isPyramidal Determine type of friction cone. .. _mj_isSparse: mj_isSparse ~~~~~~~~~~~ .. mujoco-include:: mj_isSparse Determine type of constraint Jacobian. .. _mj_isDual: mj_isDual ~~~~~~~~~ .. mujoco-include:: mj_isDual Determine type of solver (PGS is dual, CG and Newton are primal). .. _mj_mulJacVec: mj_mulJacVec ~~~~~~~~~~~~ .. mujoco-include:: mj_mulJacVec This function multiplies the constraint Jacobian ``mjData.efc_J`` by a vector. Note that the Jacobian can be either dense or sparse; the function is aware of this setting. Multiplication by J maps velocities from joint space to constraint space. .. _mj_mulJacTVec: mj_mulJacTVec ~~~~~~~~~~~~~ .. mujoco-include:: mj_mulJacTVec Same as mj_mulJacVec but multiplies by the transpose of the Jacobian. This maps forces from constraint space to joint space. .. _mj_jac: mj_jac ~~~~~~ .. mujoco-include:: mj_jac This function computes an "end-effector" Jacobian, which is unrelated to the constraint Jacobian above. Any MuJoCo body can be treated as end-effector, and the point for which the Jacobian is computed can be anywhere in space (it is treated as attached to the body). The Jacobian has translational (jacp) and rotational (jacr) components. Passing ``NULL`` for either pointer will skip part of the computation. Each component is a 3-by-nv matrix. Each row of this matrix is the gradient of the corresponding 3D coordinate of the specified point with respect to the degrees of freedom. The ability to compute end-effector Jacobians analytically is one of the advantages of working in minimal coordinates - so use it! .. _mj_jacBody: mj_jacBody ~~~~~~~~~~ .. mujoco-include:: mj_jacBody This and the remaining variants of the Jacobian function call mj_jac internally, with the center of the body, geom or site. They are just shortcuts; the same can be achieved by calling mj_jac directly. .. _mj_jacBodyCom: mj_jacBodyCom ~~~~~~~~~~~~~ .. mujoco-include:: mj_jacBodyCom Compute body center-of-mass end-effector Jacobian. .. _mj_jacSubtreeCom: mj_jacSubtreeCom ~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_jacSubtreeCom Compute subtree center-of-mass end-effector Jacobian. .. _mj_jacGeom: mj_jacGeom ~~~~~~~~~~ .. mujoco-include:: mj_jacGeom Compute geom end-effector Jacobian. .. _mj_jacSite: mj_jacSite ~~~~~~~~~~ .. mujoco-include:: mj_jacSite Compute site end-effector Jacobian. .. _mj_jacPointAxis: mj_jacPointAxis ~~~~~~~~~~~~~~~ .. mujoco-include:: mj_jacPointAxis Compute translation end-effector Jacobian of point, and rotation Jacobian of axis. .. _mj_name2id: mj_name2id ~~~~~~~~~~ .. mujoco-include:: mj_name2id Get id of object with specified name, return -1 if not found; type is mjtObj. .. _mj_id2name: mj_id2name ~~~~~~~~~~ .. mujoco-include:: mj_id2name Get name of object with specified id, return 0 if invalid type or id; type is mjtObj. .. _mj_fullM: mj_fullM ~~~~~~~~ .. mujoco-include:: mj_fullM Convert sparse inertia matrix M into full (i.e. dense) matrix. .. _mj_mulM: mj_mulM ~~~~~~~ .. mujoco-include:: mj_mulM This function multiplies the joint-space inertia matrix stored in ``mjData.qM`` by a vector. qM has a custom sparse format that the user should not attempt to manipulate directly. Alternatively one can convert qM to a dense matrix with mj_fullM and then user regular matrix-vector multiplication, but this is slower because it no longer benefits from sparsity. .. _mj_mulM2: mj_mulM2 ~~~~~~~~ .. mujoco-include:: mj_mulM2 Multiply vector by (inertia matrix)^(1/2). .. _mj_addM: mj_addM ~~~~~~~ .. mujoco-include:: mj_addM Add inertia matrix to destination matrix. Destination can be sparse uncompressed, or dense when all int* are ``NULL`` .. _mj_applyFT: mj_applyFT ~~~~~~~~~~ .. mujoco-include:: mj_applyFT This function can be used to apply a Cartesian force and torque to a point on a body, and add the result to the vector ``mjData.qfrc_applied`` of all applied forces. Note that the function requires a pointer to this vector, because sometimes we want to add the result to a different vector. .. _mj_objectVelocity: mj_objectVelocity ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_objectVelocity Compute object 6D velocity (rot:lin) in object-centered frame, world/local orientation. .. _mj_objectAcceleration: mj_objectAcceleration ~~~~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_objectAcceleration Compute object 6D acceleration (rot:lin) in object-centered frame, world/local orientation. .. _mj_contactForce: mj_contactForce ~~~~~~~~~~~~~~~ .. mujoco-include:: mj_contactForce Extract 6D force:torque given contact id, in the contact frame. .. _mj_differentiatePos: mj_differentiatePos ~~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_differentiatePos This function subtracts two vectors in the format of qpos (and divides the result by dt), while respecting the properties of quaternions. Recall that unit quaternions represent spatial orientations. They are points on the unit sphere in 4D. The tangent to that sphere is a 3D plane of rotational velocities. Thus when we subtract two quaternions in the right way, the result is a 3D vector and not a 4D vector. This the output qvel has dimensionality nv while the inputs have dimensionality nq. .. _mj_integratePos: mj_integratePos ~~~~~~~~~~~~~~~ .. mujoco-include:: mj_integratePos This is the opposite of mj_differentiatePos. It adds a vector in the format of qvel (scaled by dt) to a vector in the format of qpos. .. _mj_normalizeQuat: mj_normalizeQuat ~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_normalizeQuat Normalize all quaternions in qpos-type vector. .. _mj_local2Global: mj_local2Global ~~~~~~~~~~~~~~~ .. mujoco-include:: mj_local2Global Map from body local to global Cartesian coordinates. .. _mj_getTotalmass: mj_getTotalmass ~~~~~~~~~~~~~~~ .. mujoco-include:: mj_getTotalmass Sum all body masses. .. _mj_setTotalmass: mj_setTotalmass ~~~~~~~~~~~~~~~ .. mujoco-include:: mj_setTotalmass Scale body masses and inertias to achieve specified total mass. .. _mj_getPluginConfig: mj_getPluginConfig ~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_getPluginConfig Return a config attribute value of a plugin instance; ``NULL``: invalid plugin instance ID or attribute name .. _mj_loadPluginLibrary: mj_loadPluginLibrary ~~~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_loadPluginLibrary Load a dynamic library. The dynamic library is assumed to register one or more plugins. .. _mj_loadAllPluginLibraries: mj_loadAllPluginLibraries ~~~~~~~~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_loadAllPluginLibraries Scan a directory and load all dynamic libraries. Dynamic libraries in the specified directory are assumed to register one or more plugins. Optionally, if a callback is specified, it is called for each dynamic library encountered that registers plugins. .. _mj_version: mj_version ~~~~~~~~~~ .. mujoco-include:: mj_version Return version number: 1.0.2 is encoded as 102. .. _mj_versionString: mj_versionString ~~~~~~~~~~~~~~~~ .. mujoco-include:: mj_versionString Return the current version of MuJoCo as a null-terminated string. .. _Raycollisions: Ray collisions ^^^^^^^^^^^^^^ Ray collision functionality was added in MuJoCo 1.50. This is a new collision detection module that uses analytical formulas to intersect a ray (p + x*v, x>=0) with a geom, where p is the origin of the ray and v is the vector specifying the direction. All functions in this family return the distance to the nearest geom surface, or -1 if there is no intersection. Note that if p is inside a geom, the ray will intersect the surface from the inside which still counts as an intersection. All ray collision functions rely on quantities computed by :ref:`mj_kinematics` (see :ref:`mjData`), so must be called after :ref:`mj_kinematics`, or functions that call it (e.g. :ref:`mj_fwdPosition`). .. _mj_ray: mj_ray ~~~~~~ .. mujoco-include:: mj_ray Intersect ray (pnt+x*vec, x>=0) with visible geoms, except geoms in bodyexclude. Return geomid and distance (x) to nearest surface, or -1 if no intersection. geomgroup is an array of length mjNGROUP, where 1 means the group should be included. Pass geomgroup=``NULL`` to skip group exclusion. If flg_static is 0, static geoms will be excluded. bodyexclude=-1 can be used to indicate that all bodies are included. .. _mj_rayHfield: mj_rayHfield ~~~~~~~~~~~~ .. mujoco-include:: mj_rayHfield Intersect ray with hfield, return nearest distance or -1 if no intersection. .. _mj_rayMesh: mj_rayMesh ~~~~~~~~~~ .. mujoco-include:: mj_rayMesh Intersect ray with mesh, return nearest distance or -1 if no intersection. .. _mju_rayGeom: mju_rayGeom ~~~~~~~~~~~ .. mujoco-include:: mju_rayGeom Intersect ray with pure geom, return nearest distance or -1 if no intersection. .. _mju_raySkin: mju_raySkin ~~~~~~~~~~~ .. mujoco-include:: mju_raySkin Intersect ray with skin, return nearest distance or -1 if no intersection, and also output nearest vertex id. .. _Interaction: Interaction ^^^^^^^^^^^ These function implement abstract mouse interactions, allowing control over cameras and perturbations. Their use is well illustrated in :ref:`simulate.cc `. .. _mjv_defaultCamera: mjv_defaultCamera ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mjv_defaultCamera Set default camera. .. _mjv_defaultFreeCamera: mjv_defaultFreeCamera ~~~~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mjv_defaultFreeCamera Set default free camera. .. _mjv_defaultPerturb: mjv_defaultPerturb ~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mjv_defaultPerturb Set default perturbation. .. _mjv_room2model: mjv_room2model ~~~~~~~~~~~~~~ .. mujoco-include:: mjv_room2model Transform pose from room to model space. .. _mjv_model2room: mjv_model2room ~~~~~~~~~~~~~~ .. mujoco-include:: mjv_model2room Transform pose from model to room space. .. _mjv_cameraInModel: mjv_cameraInModel ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mjv_cameraInModel Get camera info in model space; average left and right OpenGL cameras. .. _mjv_cameraInRoom: mjv_cameraInRoom ~~~~~~~~~~~~~~~~ .. mujoco-include:: mjv_cameraInRoom Get camera info in room space; average left and right OpenGL cameras. .. _mjv_frustumHeight: mjv_frustumHeight ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mjv_frustumHeight Get frustum height at unit distance from camera; average left and right OpenGL cameras. .. _mjv_alignToCamera: mjv_alignToCamera ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mjv_alignToCamera Rotate 3D vec in horizontal plane by angle between (0,1) and (forward_x,forward_y). .. _mjv_moveCamera: mjv_moveCamera ~~~~~~~~~~~~~~ .. mujoco-include:: mjv_moveCamera Move camera with mouse; action is mjtMouse. .. _mjv_movePerturb: mjv_movePerturb ~~~~~~~~~~~~~~~ .. mujoco-include:: mjv_movePerturb Move perturb object with mouse; action is mjtMouse. .. _mjv_moveModel: mjv_moveModel ~~~~~~~~~~~~~ .. mujoco-include:: mjv_moveModel Move model with mouse; action is mjtMouse. .. _mjv_initPerturb: mjv_initPerturb ~~~~~~~~~~~~~~~ .. mujoco-include:: mjv_initPerturb Copy perturb pos,quat from selected body; set scale for perturbation. .. _mjv_applyPerturbPose: mjv_applyPerturbPose ~~~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mjv_applyPerturbPose Set perturb pos,quat in d->mocap when selected body is mocap, and in d->qpos otherwise. Write d->qpos only if flg_paused and subtree root for selected body has free joint. .. _mjv_applyPerturbForce: mjv_applyPerturbForce ~~~~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mjv_applyPerturbForce Set perturb force,torque in d->xfrc_applied, if selected body is dynamic. .. _mjv_averageCamera: mjv_averageCamera ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mjv_averageCamera Return the average of two OpenGL cameras. .. _mjv_select: mjv_select ~~~~~~~~~~ .. mujoco-include:: mjv_select This function is used for mouse selection. Previously selection was done via OpenGL, but as of MuJoCo 1.50 it relies on ray intersections which are much more efficient. aspectratio is the viewport width/height. relx and rely are the relative coordinates of the 2D point of interest in the viewport (usually mouse cursor). The function returns the id of the geom under the specified 2D point, or -1 if there is no geom (note that they skybox if present is not a model geom). The 3D coordinates of the clicked point are returned in selpnt. See :ref:`simulate.cc ` for an illustration. .. _Visualization-api: Visualization ^^^^^^^^^^^^^ The functions in this section implement abstract visualization. The results are used by the OpenGL rendered, and can also be used by users wishing to implement their own rendered, or hook up MuJoCo to advanced rendering tools such as Unity or Unreal Engine. See :ref:`simulate.cc ` for illustration of how to use these functions. .. _mjv_defaultOption: mjv_defaultOption ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mjv_defaultOption Set default visualization options. .. _mjv_defaultFigure: mjv_defaultFigure ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mjv_defaultFigure Set default figure. .. _mjv_initGeom: mjv_initGeom ~~~~~~~~~~~~ .. mujoco-include:: mjv_initGeom Initialize given geom fields when not ``NULL``, set the rest to their default values. .. _mjv_makeConnector: mjv_makeConnector ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mjv_makeConnector Set (type, size, pos, mat) for connector-type geom between given points. Assume that mjv_initGeom was already called to set all other properties. .. _mjv_defaultScene: mjv_defaultScene ~~~~~~~~~~~~~~~~ .. mujoco-include:: mjv_defaultScene Set default abstract scene. .. _mjv_makeScene: mjv_makeScene ~~~~~~~~~~~~~ .. mujoco-include:: mjv_makeScene Allocate resources in abstract scene. .. _mjv_freeScene: mjv_freeScene ~~~~~~~~~~~~~ .. mujoco-include:: mjv_freeScene Free abstract scene. .. _mjv_updateScene: mjv_updateScene ~~~~~~~~~~~~~~~ .. mujoco-include:: mjv_updateScene Update entire scene given model state. .. _mjv_addGeoms: mjv_addGeoms ~~~~~~~~~~~~ .. mujoco-include:: mjv_addGeoms Add geoms from selected categories. .. _mjv_makeLights: mjv_makeLights ~~~~~~~~~~~~~~ .. mujoco-include:: mjv_makeLights Make list of lights. .. _mjv_updateCamera: mjv_updateCamera ~~~~~~~~~~~~~~~~ .. mujoco-include:: mjv_updateCamera Update camera. .. _mjv_updateSkin: mjv_updateSkin ~~~~~~~~~~~~~~ .. mujoco-include:: mjv_updateSkin Update skins. .. _OpenGLrendering: OpenGL rendering ^^^^^^^^^^^^^^^^ These functions expose the OpenGL renderer. See :ref:`simulate.cc ` for an illustration of how to use these functions. .. _mjr_defaultContext: mjr_defaultContext ~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mjr_defaultContext Set default mjrContext. .. _mjr_makeContext: mjr_makeContext ~~~~~~~~~~~~~~~ .. mujoco-include:: mjr_makeContext Allocate resources in custom OpenGL context; fontscale is mjtFontScale. .. _mjr_changeFont: mjr_changeFont ~~~~~~~~~~~~~~ .. mujoco-include:: mjr_changeFont Change font of existing context. .. _mjr_addAux: mjr_addAux ~~~~~~~~~~ .. mujoco-include:: mjr_addAux Add Aux buffer with given index to context; free previous Aux buffer. .. _mjr_freeContext: mjr_freeContext ~~~~~~~~~~~~~~~ .. mujoco-include:: mjr_freeContext Free resources in custom OpenGL context, set to default. .. _mjr_uploadTexture: mjr_uploadTexture ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mjr_uploadTexture Upload texture to GPU, overwriting previous upload if any. .. _mjr_uploadMesh: mjr_uploadMesh ~~~~~~~~~~~~~~ .. mujoco-include:: mjr_uploadMesh Upload mesh to GPU, overwriting previous upload if any. .. _mjr_uploadHField: mjr_uploadHField ~~~~~~~~~~~~~~~~ .. mujoco-include:: mjr_uploadHField Upload height field to GPU, overwriting previous upload if any. .. _mjr_restoreBuffer: mjr_restoreBuffer ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mjr_restoreBuffer Make con->currentBuffer current again. .. _mjr_setBuffer: mjr_setBuffer ~~~~~~~~~~~~~ .. mujoco-include:: mjr_setBuffer Set OpenGL framebuffer for rendering: mjFB_WINDOW or mjFB_OFFSCREEN. If only one buffer is available, set that buffer and ignore framebuffer argument. .. _mjr_readPixels: mjr_readPixels ~~~~~~~~~~~~~~ .. mujoco-include:: mjr_readPixels Read pixels from current OpenGL framebuffer to client buffer. Viewport is in OpenGL framebuffer; client buffer starts at (0,0). .. _mjr_drawPixels: mjr_drawPixels ~~~~~~~~~~~~~~ .. mujoco-include:: mjr_drawPixels Draw pixels from client buffer to current OpenGL framebuffer. Viewport is in OpenGL framebuffer; client buffer starts at (0,0). .. _mjr_blitBuffer: mjr_blitBuffer ~~~~~~~~~~~~~~ .. mujoco-include:: mjr_blitBuffer Blit from src viewpoint in current framebuffer to dst viewport in other framebuffer. If src, dst have different size and flg_depth==0, color is interpolated with GL_LINEAR. .. _mjr_setAux: mjr_setAux ~~~~~~~~~~ .. mujoco-include:: mjr_setAux Set Aux buffer for custom OpenGL rendering (call restoreBuffer when done). .. _mjr_blitAux: mjr_blitAux ~~~~~~~~~~~ .. mujoco-include:: mjr_blitAux Blit from Aux buffer to con->currentBuffer. .. _mjr_text: mjr_text ~~~~~~~~ .. mujoco-include:: mjr_text Draw text at (x,y) in relative coordinates; font is mjtFont. .. _mjr_overlay: mjr_overlay ~~~~~~~~~~~ .. mujoco-include:: mjr_overlay Draw text overlay; font is mjtFont; gridpos is mjtGridPos. .. _mjr_maxViewport: mjr_maxViewport ~~~~~~~~~~~~~~~ .. mujoco-include:: mjr_maxViewport Get maximum viewport for active buffer. .. _mjr_rectangle: mjr_rectangle ~~~~~~~~~~~~~ .. mujoco-include:: mjr_rectangle Draw rectangle. .. _mjr_label: mjr_label ~~~~~~~~~ .. mujoco-include:: mjr_label Draw rectangle with centered text. .. _mjr_figure: mjr_figure ~~~~~~~~~~ .. mujoco-include:: mjr_figure Draw 2D figure. .. _mjr_render: mjr_render ~~~~~~~~~~ .. mujoco-include:: mjr_render Render 3D scene. .. _mjr_finish: mjr_finish ~~~~~~~~~~ .. mujoco-include:: mjr_finish Call glFinish. .. _mjr_getError: mjr_getError ~~~~~~~~~~~~ .. mujoco-include:: mjr_getError Call glGetError and return result. .. _mjr_findRect: mjr_findRect ~~~~~~~~~~~~ .. mujoco-include:: mjr_findRect Find first rectangle containing mouse, -1: not found. .. _UIframework: UI framework ^^^^^^^^^^^^ .. _mjui_themeSpacing: mjui_themeSpacing ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mjui_themeSpacing Get builtin UI theme spacing (ind: 0-1). .. _mjui_themeColor: mjui_themeColor ~~~~~~~~~~~~~~~ .. mujoco-include:: mjui_themeColor Get builtin UI theme color (ind: 0-3). .. _mjui_add: mjui_add ~~~~~~~~ .. mujoco-include:: mjui_add Add definitions to UI. .. _mjui_addToSection: mjui_addToSection ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mjui_addToSection Add definitions to UI section. .. _mjui_resize: mjui_resize ~~~~~~~~~~~ .. mujoco-include:: mjui_resize Compute UI sizes. .. _mjui_update: mjui_update ~~~~~~~~~~~ .. mujoco-include:: mjui_update Update specific section/item; -1: update all. .. _mjui_event: mjui_event ~~~~~~~~~~ .. mujoco-include:: mjui_event Handle UI event, return pointer to changed item, ``NULL`` if no change. .. _mjui_render: mjui_render ~~~~~~~~~~~ .. mujoco-include:: mjui_render Copy UI image to current buffer. .. _Errorandmemory: Error and memory ^^^^^^^^^^^^^^^^ .. _mju_error: mju_error ~~~~~~~~~ .. mujoco-include:: mju_error Main error function; does not return to caller. .. _mju_error_i: mju_error_i ~~~~~~~~~~~ .. mujoco-include:: mju_error_i Error function with int argument; msg is a printf format string. .. _mju_error_s: mju_error_s ~~~~~~~~~~~ .. mujoco-include:: mju_error_s Error function with string argument. .. _mju_warning: mju_warning ~~~~~~~~~~~ .. mujoco-include:: mju_warning Main warning function; returns to caller. .. _mju_warning_i: mju_warning_i ~~~~~~~~~~~~~ .. mujoco-include:: mju_warning_i Warning function with int argument. .. _mju_warning_s: mju_warning_s ~~~~~~~~~~~~~ .. mujoco-include:: mju_warning_s Warning function with string argument. .. _mju_clearHandlers: mju_clearHandlers ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mju_clearHandlers Clear user error and memory handlers. .. _mju_malloc: mju_malloc ~~~~~~~~~~ .. mujoco-include:: mju_malloc Allocate memory; byte-align on 64; pad size to multiple of 64. .. _mju_free: mju_free ~~~~~~~~ .. mujoco-include:: mju_free Free memory, using free() by default. .. _mj_warning: mj_warning ~~~~~~~~~~ .. mujoco-include:: mj_warning High-level warning function: count warnings in ``mjData``, print only the first. .. _mju_writeLog: mju_writeLog ~~~~~~~~~~~~ .. mujoco-include:: mju_writeLog Write [datetime, type: message] to MUJOCO_LOG.TXT. .. _Activation: Activation ^^^^^^^^^^ The functions in this section are maintained for backward compatibility with the now-removed activation mechanism. .. _mj_activate: mj_activate ~~~~~~~~~~~ .. mujoco-include:: mj_activate Return 1 (for backward compatibility). .. _mj_deactivate: mj_deactivate ~~~~~~~~~~~~~ .. mujoco-include:: mj_deactivate Do nothing (for backward compatibility). .. _Standardmath: Standard math ^^^^^^^^^^^^^ The "functions" in this section are preprocessor macros replaced with the corresponding C standard library math functions. When MuJoCo is compiled with single precision (which is not currently available to the public, but we sometimes use it internally) these macros are replaced with the corresponding single-precision functions (not shown here). So one can think of them as having inputs and outputs of type mjtNum, where mjtNum is defined as double or float depending on how MuJoCo is compiled. We will not document these functions here; see the C standard library specification. mju_sqrt ~~~~~~~~ .. code-block:: C #define mju_sqrt sqrt mju_exp ~~~~~~~ .. code-block:: C #define mju_exp exp mju_sin ~~~~~~~ .. code-block:: C #define mju_sin sin mju_cos ~~~~~~~ .. code-block:: C #define mju_cos cos mju_tan ~~~~~~~ .. code-block:: C #define mju_tan tan mju_asin ~~~~~~~~ .. code-block:: C #define mju_asin asin mju_acos ~~~~~~~~ .. code-block:: C #define mju_acos acos mju_atan2 ~~~~~~~~~ .. code-block:: C #define mju_atan2 atan2 mju_tanh ~~~~~~~~ .. code-block:: C #define mju_tanh tanh mju_pow ~~~~~~~ .. code-block:: C #define mju_pow pow mju_abs ~~~~~~~ .. code-block:: C #define mju_abs fabs mju_log ~~~~~~~ .. code-block:: C #define mju_log log mju_log10 ~~~~~~~~~ .. code-block:: C #define mju_log10 log10 mju_floor ~~~~~~~~~ .. code-block:: C #define mju_floor floor mju_ceil ~~~~~~~~ .. code-block:: C #define mju_ceil ceil .. _Vectormath: Vector math ^^^^^^^^^^^ .. _mju_zero3: mju_zero3 ~~~~~~~~~ .. mujoco-include:: mju_zero3 Set res = 0. .. _mju_copy3: mju_copy3 ~~~~~~~~~ .. mujoco-include:: mju_copy3 Set res = vec. .. _mju_scl3: mju_scl3 ~~~~~~~~ .. mujoco-include:: mju_scl3 Set res = vec*scl. .. _mju_add3: mju_add3 ~~~~~~~~ .. mujoco-include:: mju_add3 Set res = vec1 + vec2. .. _mju_sub3: mju_sub3 ~~~~~~~~ .. mujoco-include:: mju_sub3 Set res = vec1 - vec2. .. _mju_addTo3: mju_addTo3 ~~~~~~~~~~ .. mujoco-include:: mju_addTo3 Set res = res + vec. .. _mju_subFrom3: mju_subFrom3 ~~~~~~~~~~~~ .. mujoco-include:: mju_subFrom3 Set res = res - vec. .. _mju_addToScl3: mju_addToScl3 ~~~~~~~~~~~~~ .. mujoco-include:: mju_addToScl3 Set res = res + vec*scl. .. _mju_addScl3: mju_addScl3 ~~~~~~~~~~~ .. mujoco-include:: mju_addScl3 Set res = vec1 + vec2*scl. .. _mju_normalize3: mju_normalize3 ~~~~~~~~~~~~~~ .. mujoco-include:: mju_normalize3 Normalize vector, return length before normalization. .. _mju_norm3: mju_norm3 ~~~~~~~~~ .. mujoco-include:: mju_norm3 Return vector length (without normalizing the vector). .. _mju_dot3: mju_dot3 ~~~~~~~~ .. mujoco-include:: mju_dot3 Return dot-product of vec1 and vec2. .. _mju_dist3: mju_dist3 ~~~~~~~~~ .. mujoco-include:: mju_dist3 Return Cartesian distance between 3D vectors pos1 and pos2. .. _mju_rotVecMat: mju_rotVecMat ~~~~~~~~~~~~~ .. mujoco-include:: mju_rotVecMat Multiply vector by 3D rotation matrix: res = mat * vec. .. _mju_rotVecMatT: mju_rotVecMatT ~~~~~~~~~~~~~~ .. mujoco-include:: mju_rotVecMatT Multiply vector by transposed 3D rotation matrix: res = mat' * vec. .. _mju_cross: mju_cross ~~~~~~~~~ .. mujoco-include:: mju_cross Compute cross-product: res = cross(a, b). .. _mju_zero4: mju_zero4 ~~~~~~~~~ .. mujoco-include:: mju_zero4 Set res = 0. .. _mju_unit4: mju_unit4 ~~~~~~~~~ .. mujoco-include:: mju_unit4 Set res = (1,0,0,0). .. _mju_copy4: mju_copy4 ~~~~~~~~~ .. mujoco-include:: mju_copy4 Set res = vec. .. _mju_normalize4: mju_normalize4 ~~~~~~~~~~~~~~ .. mujoco-include:: mju_normalize4 Normalize vector, return length before normalization. .. _mju_zero: mju_zero ~~~~~~~~ .. mujoco-include:: mju_zero Set res = 0. .. _mju_fill: mju_fill ~~~~~~~~ .. mujoco-include:: mju_fill Set res = val. .. _mju_copy: mju_copy ~~~~~~~~ .. mujoco-include:: mju_copy Set res = vec. .. _mju_sum: mju_sum ~~~~~~~ .. mujoco-include:: mju_sum Return sum(vec). .. _mju_L1: mju_L1 ~~~~~~ .. mujoco-include:: mju_L1 Return L1 norm: sum(abs(vec)). .. _mju_scl: mju_scl ~~~~~~~ .. mujoco-include:: mju_scl Set res = vec*scl. .. _mju_add: mju_add ~~~~~~~ .. mujoco-include:: mju_add Set res = vec1 + vec2. .. _mju_sub: mju_sub ~~~~~~~ .. mujoco-include:: mju_sub Set res = vec1 - vec2. .. _mju_addTo: mju_addTo ~~~~~~~~~ .. mujoco-include:: mju_addTo Set res = res + vec. .. _mju_subFrom: mju_subFrom ~~~~~~~~~~~ .. mujoco-include:: mju_subFrom Set res = res - vec. .. _mju_addToScl: mju_addToScl ~~~~~~~~~~~~ .. mujoco-include:: mju_addToScl Set res = res + vec*scl. .. _mju_addScl: mju_addScl ~~~~~~~~~~ .. mujoco-include:: mju_addScl Set res = vec1 + vec2*scl. .. _mju_normalize: mju_normalize ~~~~~~~~~~~~~ .. mujoco-include:: mju_normalize Normalize vector, return length before normalization. .. _mju_norm: mju_norm ~~~~~~~~ .. mujoco-include:: mju_norm Return vector length (without normalizing vector). .. _mju_dot: mju_dot ~~~~~~~ .. mujoco-include:: mju_dot Return dot-product of vec1 and vec2. .. _mju_mulMatVec: mju_mulMatVec ~~~~~~~~~~~~~ .. mujoco-include:: mju_mulMatVec Multiply matrix and vector: res = mat * vec. .. _mju_mulMatTVec: mju_mulMatTVec ~~~~~~~~~~~~~~ .. mujoco-include:: mju_mulMatTVec Multiply transposed matrix and vector: res = mat' * vec. .. _mju_mulVecMatVec: mju_mulVecMatVec ~~~~~~~~~~~~~~~~ .. mujoco-include:: mju_mulVecMatVec Multiply square matrix with vectors on both sides: returns vec1' * mat * vec2. .. _mju_transpose: mju_transpose ~~~~~~~~~~~~~ .. mujoco-include:: mju_transpose Transpose matrix: res = mat'. .. _mju_symmetrize: mju_symmetrize ~~~~~~~~~~~~~~ .. mujoco-include:: mju_symmetrize Symmetrize square matrix :math:`R = \frac{1}{2}(M + M^T)`. .. _mju_eye: mju_eye ~~~~~~~ .. mujoco-include:: mju_eye Set mat to the identity matrix. .. _mju_mulMatMat: mju_mulMatMat ~~~~~~~~~~~~~ .. mujoco-include:: mju_mulMatMat Multiply matrices: res = mat1 * mat2. .. _mju_mulMatMatT: mju_mulMatMatT ~~~~~~~~~~~~~~ .. mujoco-include:: mju_mulMatMatT Multiply matrices, second argument transposed: res = mat1 * mat2'. .. _mju_mulMatTMat: mju_mulMatTMat ~~~~~~~~~~~~~~ .. mujoco-include:: mju_mulMatTMat Multiply matrices, first argument transposed: res = mat1' * mat2. .. _mju_sqrMatTD: mju_sqrMatTD ~~~~~~~~~~~~ .. mujoco-include:: mju_sqrMatTD Set res = mat' * diag * mat if diag is not ``NULL``, and res = mat' * mat otherwise. .. _mju_transformSpatial: mju_transformSpatial ~~~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mju_transformSpatial Coordinate transform of 6D motion or force vector in rotation:translation format. rotnew2old is 3-by-3, ``NULL`` means no rotation; flg_force specifies force or motion type. .. _Quaternions: Quaternions ^^^^^^^^^^^ .. _mju_rotVecQuat: mju_rotVecQuat ~~~~~~~~~~~~~~ .. mujoco-include:: mju_rotVecQuat Rotate vector by quaternion. .. _mju_negQuat: mju_negQuat ~~~~~~~~~~~ .. mujoco-include:: mju_negQuat Conjugate quaternion, corresponding to opposite rotation. .. _mju_mulQuat: mju_mulQuat ~~~~~~~~~~~ .. mujoco-include:: mju_mulQuat Multiply quaternions. .. _mju_mulQuatAxis: mju_mulQuatAxis ~~~~~~~~~~~~~~~ .. mujoco-include:: mju_mulQuatAxis Multiply quaternion and axis. .. _mju_axisAngle2Quat: mju_axisAngle2Quat ~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mju_axisAngle2Quat Convert axisAngle to quaternion. .. _mju_quat2Vel: mju_quat2Vel ~~~~~~~~~~~~ .. mujoco-include:: mju_quat2Vel Convert quaternion (corresponding to orientation difference) to 3D velocity. .. _mju_subQuat: mju_subQuat ~~~~~~~~~~~ .. mujoco-include:: mju_subQuat Subtract quaternions, express as 3D velocity: qb*quat(res) = qa. .. _mju_quat2Mat: mju_quat2Mat ~~~~~~~~~~~~ .. mujoco-include:: mju_quat2Mat Convert quaternion to 3D rotation matrix. .. _mju_mat2Quat: mju_mat2Quat ~~~~~~~~~~~~ .. mujoco-include:: mju_mat2Quat Convert 3D rotation matrix to quaternion. .. _mju_derivQuat: mju_derivQuat ~~~~~~~~~~~~~ .. mujoco-include:: mju_derivQuat Compute time-derivative of quaternion, given 3D rotational velocity. .. _mju_quatIntegrate: mju_quatIntegrate ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mju_quatIntegrate Integrate quaternion given 3D angular velocity. .. _mju_quatZ2Vec: mju_quatZ2Vec ~~~~~~~~~~~~~ .. mujoco-include:: mju_quatZ2Vec Construct quaternion performing rotation from z-axis to given vector. .. _Poses: Poses ^^^^^ .. _mju_mulPose: mju_mulPose ~~~~~~~~~~~ .. mujoco-include:: mju_mulPose Multiply two poses. .. _mju_negPose: mju_negPose ~~~~~~~~~~~ .. mujoco-include:: mju_negPose Conjugate pose, corresponding to the opposite spatial transformation. .. _mju_trnVecPose: mju_trnVecPose ~~~~~~~~~~~~~~ .. mujoco-include:: mju_trnVecPose Transform vector by pose. .. _Decompositions: Decompositions / Solvers ^^^^^^^^^^^^^^^^^^^^^^^^ .. _mju_cholFactor: mju_cholFactor ~~~~~~~~~~~~~~ .. mujoco-include:: mju_cholFactor Cholesky decomposition: mat = L*L'; return rank, decomposition performed in-place into mat. .. _mju_cholSolve: mju_cholSolve ~~~~~~~~~~~~~ .. mujoco-include:: mju_cholSolve Solve mat * res = vec, where mat is Cholesky-factorized .. _mju_cholUpdate: mju_cholUpdate ~~~~~~~~~~~~~~ .. mujoco-include:: mju_cholUpdate Cholesky rank-one update: L*L' +/- x*x'; return rank. .. _mju_eig3: mju_eig3 ~~~~~~~~ .. mujoco-include:: mju_eig3 Eigenvalue decomposition of symmetric 3x3 matrix. .. _mju_boxQP: mju_boxQP ~~~~~~~~~ .. mujoco-include:: mju_boxQP Minimize :math:`\tfrac{1}{2} x^T H x + x^T g \quad \text{s.t.} \quad l \le x \le u`, return rank or -1 if failed. inputs: ``n`` - problem dimension ``H`` - SPD matrix ``n*n`` ``g`` - bias vector ``n`` ``lower`` - lower bounds ``n`` ``upper`` - upper bounds ``n`` ``res`` - solution warmstart ``n`` return value: ``nfree <= n`` - rank of unconstrained subspace, -1 if failure outputs (required): ``res`` - solution ``n`` ``R`` - subspace Cholesky factor ``nfree*nfree``, allocated: ``n*(n+7)`` outputs (optional): ``index`` - set of free dimensions ``nfree``, allocated: ``n`` notes: The initial value of ``res`` is used to warmstart the solver. ``R`` must have allocatd size ``n*(n+7)``, but only ``nfree*nfree`` values are used in output. ``index`` (if given) must have allocated size ``n``, but only ``nfree`` values are used in output. The convenience function :ref:`mju_boxQPmalloc` allocates the required data structures. Only the lower triangles of H and R and are read from and written to, respectively. .. _mju_boxQPmalloc: mju_boxQPmalloc ~~~~~~~~~~~~~~~ .. mujoco-include:: mju_boxQPmalloc Allocate heap memory for box-constrained Quadratic Program. As in :ref:`mju_boxQP`, ``index``, ``lower``, and ``upper`` are optional. Free all pointers with ``mju_free()``. .. _Miscellaneous: Miscellaneous ^^^^^^^^^^^^^ .. _mju_muscleGain: mju_muscleGain ~~~~~~~~~~~~~~ .. mujoco-include:: mju_muscleGain Muscle active force, prm = (range[2], force, scale, lmin, lmax, vmax, fpmax, fvmax). .. _mju_muscleBias: mju_muscleBias ~~~~~~~~~~~~~~ .. mujoco-include:: mju_muscleBias Muscle passive force, prm = (range[2], force, scale, lmin, lmax, vmax, fpmax, fvmax). .. _mju_muscleDynamics: mju_muscleDynamics ~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mju_muscleDynamics Muscle activation dynamics, prm = (tau_act, tau_deact). .. _mju_encodePyramid: mju_encodePyramid ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mju_encodePyramid Convert contact force to pyramid representation. .. _mju_decodePyramid: mju_decodePyramid ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mju_decodePyramid Convert pyramid representation to contact force. .. _mju_springDamper: mju_springDamper ~~~~~~~~~~~~~~~~ .. mujoco-include:: mju_springDamper Integrate spring-damper analytically, return pos(dt). .. _mju_min: mju_min ~~~~~~~ .. mujoco-include:: mju_min Return min(a,b) with single evaluation of a and b. .. _mju_max: mju_max ~~~~~~~ .. mujoco-include:: mju_max Return max(a,b) with single evaluation of a and b. .. _mju_clip: mju_clip ~~~~~~~~ .. mujoco-include:: mju_clip Clip x to the range [min, max]. .. _mju_sign: mju_sign ~~~~~~~~ .. mujoco-include:: mju_sign Return sign of x: +1, -1 or 0. .. _mju_round: mju_round ~~~~~~~~~ .. mujoco-include:: mju_round Round x to nearest integer. .. _mju_type2Str: mju_type2Str ~~~~~~~~~~~~ .. mujoco-include:: mju_type2Str Convert type id (mjtObj) to type name. .. _mju_str2Type: mju_str2Type ~~~~~~~~~~~~ .. mujoco-include:: mju_str2Type Convert type name to type id (mjtObj). .. _mju_writeNumBytes: mju_writeNumBytes ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mju_writeNumBytes Return human readable number of bytes using standard letter suffix. .. _mju_warningText: mju_warningText ~~~~~~~~~~~~~~~ .. mujoco-include:: mju_warningText Construct a warning message given the warning type and info. .. _mju_isBad: mju_isBad ~~~~~~~~~ .. mujoco-include:: mju_isBad Return 1 if nan or abs(x)>mjMAXVAL, 0 otherwise. Used by check functions. .. _mju_isZero: mju_isZero ~~~~~~~~~~ .. mujoco-include:: mju_isZero Return 1 if all elements are 0. .. _mju_standardNormal: mju_standardNormal ~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mju_standardNormal Standard normal random number generator (optional second number). .. _mju_f2n: mju_f2n ~~~~~~~ .. mujoco-include:: mju_f2n Convert from float to mjtNum. .. _mju_n2f: mju_n2f ~~~~~~~ .. mujoco-include:: mju_n2f Convert from mjtNum to float. .. _mju_d2n: mju_d2n ~~~~~~~ .. mujoco-include:: mju_d2n Convert from double to mjtNum. .. _mju_n2d: mju_n2d ~~~~~~~ .. mujoco-include:: mju_n2d Convert from mjtNum to double. .. _mju_insertionSort: mju_insertionSort ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mju_insertionSort Insertion sort, resulting list is in increasing order. .. _mju_insertionSortInt: mju_insertionSortInt ~~~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mju_insertionSortInt Integer insertion sort, resulting list is in increasing order. .. _mju_Halton: mju_Halton ~~~~~~~~~~ .. mujoco-include:: mju_Halton Generate Halton sequence. .. _mju_strncpy: mju_strncpy ~~~~~~~~~~~ .. mujoco-include:: mju_strncpy Call strncpy, then set dst[n-1] = 0. .. _mju_sigmoid: mju_sigmoid ~~~~~~~~~~~ .. mujoco-include:: mju_sigmoid Sigmoid function over 0<=x<=1 constructed from half-quadratics. .. _Derivatives-api: Derivatives ^^^^^^^^^^^ .. _mjd_transitionFD: mjd_transitionFD ~~~~~~~~~~~~~~~~ .. mujoco-include:: mjd_transitionFD Finite differenced transition matrices. Letting :math:`x, u` denote the current :ref:`state` and control vectors and letting :math:`y, s` denote the next state and sensor values, the top-level :ref:`mj_step` function computes :math:`(x,u) \rightarrow (y,s)`. :ref:`mjd_transitionFD` computes the four associated Jacobians using finite-differencing. These matrices and their dimensions are: .. csv-table:: :header: "matrix", "Jacobian", "dimension" :widths: auto :align: left ``A``, :math:`\partial y / \partial x`, ``2*nv+na x 2*nv+na`` ``B``, :math:`\partial y / \partial u`, ``2*nv+na x nu`` ``C``, :math:`\partial s / \partial x`, ``nsensordata x 2*nv+na`` ``D``, :math:`\partial s / \partial u`, ``nsensordata x nu`` - All four matrix outputs are optional (can be ``NULL``). - ``eps`` is the finite-differencing epsilon. - ``centered`` is a flag denoting whether to use forward (0) or centered (1) differences. .. _Plugins-api: Plugins ^^^^^^^ .. _mjp_defaultPlugin: mjp_defaultPlugin ~~~~~~~~~~~~~~~~~ .. mujoco-include:: mjp_defaultPlugin Set default plugin definition. .. _mjp_registerPlugin: mjp_registerPlugin ~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mjp_registerPlugin Globally register a plugin. This function is thread-safe. If an identical mjpPlugin is already registered, this function does nothing. If a non-identical mjpPlugin with the same name is already registered, an mju_error is raised. Two mjpPlugins are considered identical if all member function pointers and numbers are equal, and the name and attribute strings are all identical, however the char pointers to the strings need not be the same. .. _mjp_pluginCount: mjp_pluginCount ~~~~~~~~~~~~~~~ .. mujoco-include:: mjp_pluginCount Return the number of globally registered plugins. .. _mjp_getPlugin: mjp_getPlugin ~~~~~~~~~~~~~ .. mujoco-include:: mjp_getPlugin Look up a plugin by name. If slot is not ``NULL``, also write its registered slot number into it. .. _mjp_getPluginAtSlot: mjp_getPluginAtSlot ~~~~~~~~~~~~~~~~~~~ .. mujoco-include:: mjp_getPluginAtSlot Look up a plugin by the registered slot number that was returned by mjp_registerPlugin.