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69 KiB
C

// Copyright 2021 DeepMind Technologies Limited
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef MUJOCO_MJMODEL_H_
#define MUJOCO_MJMODEL_H_
#include <stddef.h>
#include <stdint.h>
#include <mujoco/mjtnum.h>
// global constants
#define mjPI 3.14159265358979323846
#define mjMAXVAL 1E+10 // maximum value in qpos, qvel, qacc
#define mjMINMU 1E-5 // minimum friction coefficient
#define mjMINIMP 0.0001 // minimum constraint impedance
#define mjMAXIMP 0.9999 // maximum constraint impedance
#define mjMAXCONPAIR 50 // maximum number of contacts per geom pair
#define mjMAXTREEDEPTH 50 // maximum bounding volume hierarchy depth
//---------------------------------- sizes ---------------------------------------------------------
#define mjNEQDATA 11 // number of eq_data fields
#define mjNDYN 10 // number of actuator dynamics parameters
#define mjNGAIN 10 // number of actuator gain parameters
#define mjNBIAS 10 // number of actuator bias parameters
#define mjNFLUID 12 // number of fluid interaction parameters
#define mjNREF 2 // number of solver reference parameters
#define mjNIMP 5 // number of solver impedance parameters
#define mjNSOLVER 200 // size of one mjData.solver array
#define mjNISLAND 20 // number of mjData.solver arrays
//---------------------------------- enum types (mjt) ----------------------------------------------
typedef enum mjtDisableBit_ { // disable default feature bitflags
mjDSBL_CONSTRAINT = 1<<0, // entire constraint solver
mjDSBL_EQUALITY = 1<<1, // equality constraints
mjDSBL_FRICTIONLOSS = 1<<2, // joint and tendon frictionloss constraints
mjDSBL_LIMIT = 1<<3, // joint and tendon limit constraints
mjDSBL_CONTACT = 1<<4, // contact constraints
mjDSBL_PASSIVE = 1<<5, // passive forces
mjDSBL_GRAVITY = 1<<6, // gravitational forces
mjDSBL_CLAMPCTRL = 1<<7, // clamp control to specified range
mjDSBL_WARMSTART = 1<<8, // warmstart constraint solver
mjDSBL_FILTERPARENT = 1<<9, // remove collisions with parent body
mjDSBL_ACTUATION = 1<<10, // apply actuation forces
mjDSBL_REFSAFE = 1<<11, // integrator safety: make ref[0]>=2*timestep
mjDSBL_SENSOR = 1<<12, // sensors
mjDSBL_MIDPHASE = 1<<13, // mid-phase collision filtering
mjDSBL_EULERDAMP = 1<<14, // implicit integration of joint damping in Euler integrator
mjDSBL_AUTORESET = 1<<15, // automatic reset when numerical issues are detected
mjNDISABLE = 16 // number of disable flags
} mjtDisableBit;
typedef enum mjtEnableBit_ { // enable optional feature bitflags
mjENBL_OVERRIDE = 1<<0, // override contact parameters
mjENBL_ENERGY = 1<<1, // energy computation
mjENBL_FWDINV = 1<<2, // record solver statistics
mjENBL_INVDISCRETE = 1<<3, // discrete-time inverse dynamics
// experimental features:
mjENBL_MULTICCD = 1<<4, // multi-point convex collision detection
mjENBL_ISLAND = 1<<5, // constraint island discovery
mjENBL_NATIVECCD = 1<<6, // native convex collision detection
mjNENABLE = 7 // number of enable flags
} mjtEnableBit;
typedef enum mjtJoint_ { // type of degree of freedom
mjJNT_FREE = 0, // global position and orientation (quat) (7)
mjJNT_BALL, // orientation (quat) relative to parent (4)
mjJNT_SLIDE, // sliding distance along body-fixed axis (1)
mjJNT_HINGE // rotation angle (rad) around body-fixed axis (1)
} mjtJoint;
typedef enum mjtGeom_ { // type of geometric shape
// regular geom types
mjGEOM_PLANE = 0, // plane
mjGEOM_HFIELD, // height field
mjGEOM_SPHERE, // sphere
mjGEOM_CAPSULE, // capsule
mjGEOM_ELLIPSOID, // ellipsoid
mjGEOM_CYLINDER, // cylinder
mjGEOM_BOX, // box
mjGEOM_MESH, // mesh
mjGEOM_SDF, // signed distance field
mjNGEOMTYPES, // number of regular geom types
// rendering-only geom types: not used in mjModel, not counted in mjNGEOMTYPES
mjGEOM_ARROW = 100, // arrow
mjGEOM_ARROW1, // arrow without wedges
mjGEOM_ARROW2, // arrow in both directions
mjGEOM_LINE, // line
mjGEOM_LINEBOX, // box with line edges
mjGEOM_FLEX, // flex
mjGEOM_SKIN, // skin
mjGEOM_LABEL, // text label
mjGEOM_TRIANGLE, // triangle
mjGEOM_NONE = 1001 // missing geom type
} mjtGeom;
typedef enum mjtCamLight_ { // tracking mode for camera and light
mjCAMLIGHT_FIXED = 0, // pos and rot fixed in body
mjCAMLIGHT_TRACK, // pos tracks body, rot fixed in global
mjCAMLIGHT_TRACKCOM, // pos tracks subtree com, rot fixed in body
mjCAMLIGHT_TARGETBODY, // pos fixed in body, rot tracks target body
mjCAMLIGHT_TARGETBODYCOM // pos fixed in body, rot tracks target subtree com
} mjtCamLight;
typedef enum mjtTexture_ { // type of texture
mjTEXTURE_2D = 0, // 2d texture, suitable for planes and hfields
mjTEXTURE_CUBE, // cube texture, suitable for all other geom types
mjTEXTURE_SKYBOX // cube texture used as skybox
} mjtTexture;
typedef enum mjtTextureRole_ { // role of texture map in rendering
mjTEXROLE_USER = 0, // unspecified
mjTEXROLE_RGB, // base color (albedo)
mjTEXROLE_OCCLUSION, // ambient occlusion
mjTEXROLE_ROUGHNESS, // roughness
mjTEXROLE_METALLIC, // metallic
mjTEXROLE_NORMAL, // normal (bump) map
mjTEXROLE_OPACITY, // transperancy
mjTEXROLE_EMISSIVE, // light emission
mjTEXROLE_RGBA, // base color, opacity
mjTEXROLE_ORM, // occlusion, roughness, metallic
mjNTEXROLE
} mjtTextureRole;
typedef enum mjtIntegrator_ { // integrator mode
mjINT_EULER = 0, // semi-implicit Euler
mjINT_RK4, // 4th-order Runge Kutta
mjINT_IMPLICIT, // implicit in velocity
mjINT_IMPLICITFAST // implicit in velocity, no rne derivative
} mjtIntegrator;
typedef enum mjtCone_ { // type of friction cone
mjCONE_PYRAMIDAL = 0, // pyramidal
mjCONE_ELLIPTIC // elliptic
} mjtCone;
typedef enum mjtJacobian_ { // type of constraint Jacobian
mjJAC_DENSE = 0, // dense
mjJAC_SPARSE, // sparse
mjJAC_AUTO // dense if nv<60, sparse otherwise
} mjtJacobian;
typedef enum mjtSolver_ { // constraint solver algorithm
mjSOL_PGS = 0, // PGS (dual)
mjSOL_CG, // CG (primal)
mjSOL_NEWTON // Newton (primal)
} mjtSolver;
typedef enum mjtEq_ { // type of equality constraint
mjEQ_CONNECT = 0, // connect two bodies at a point (ball joint)
mjEQ_WELD, // fix relative position and orientation of two bodies
mjEQ_JOINT, // couple the values of two scalar joints with cubic
mjEQ_TENDON, // couple the lengths of two tendons with cubic
mjEQ_FLEX, // fix all edge lengths of a flex
mjEQ_DISTANCE // unsupported, will cause an error if used
} mjtEq;
typedef enum mjtWrap_ { // type of tendon wrap object
mjWRAP_NONE = 0, // null object
mjWRAP_JOINT, // constant moment arm
mjWRAP_PULLEY, // pulley used to split tendon
mjWRAP_SITE, // pass through site
mjWRAP_SPHERE, // wrap around sphere
mjWRAP_CYLINDER // wrap around (infinite) cylinder
} mjtWrap;
typedef enum mjtTrn_ { // type of actuator transmission
mjTRN_JOINT = 0, // force on joint
mjTRN_JOINTINPARENT, // force on joint, expressed in parent frame
mjTRN_SLIDERCRANK, // force via slider-crank linkage
mjTRN_TENDON, // force on tendon
mjTRN_SITE, // force on site
mjTRN_BODY, // adhesion force on a body's geoms
mjTRN_UNDEFINED = 1000 // undefined transmission type
} mjtTrn;
typedef enum mjtDyn_ { // type of actuator dynamics
mjDYN_NONE = 0, // no internal dynamics; ctrl specifies force
mjDYN_INTEGRATOR, // integrator: da/dt = u
mjDYN_FILTER, // linear filter: da/dt = (u-a) / tau
mjDYN_FILTEREXACT, // linear filter: da/dt = (u-a) / tau, with exact integration
mjDYN_MUSCLE, // piece-wise linear filter with two time constants
mjDYN_USER // user-defined dynamics type
} mjtDyn;
typedef enum mjtGain_ { // type of actuator gain
mjGAIN_FIXED = 0, // fixed gain
mjGAIN_AFFINE, // const + kp*length + kv*velocity
mjGAIN_MUSCLE, // muscle FLV curve computed by mju_muscleGain()
mjGAIN_USER // user-defined gain type
} mjtGain;
typedef enum mjtBias_ { // type of actuator bias
mjBIAS_NONE = 0, // no bias
mjBIAS_AFFINE, // const + kp*length + kv*velocity
mjBIAS_MUSCLE, // muscle passive force computed by mju_muscleBias()
mjBIAS_USER // user-defined bias type
} mjtBias;
typedef enum mjtObj_ { // type of MujoCo object
mjOBJ_UNKNOWN = 0, // unknown object type
mjOBJ_BODY, // body
mjOBJ_XBODY, // body, used to access regular frame instead of i-frame
mjOBJ_JOINT, // joint
mjOBJ_DOF, // dof
mjOBJ_GEOM, // geom
mjOBJ_SITE, // site
mjOBJ_CAMERA, // camera
mjOBJ_LIGHT, // light
mjOBJ_FLEX, // flex
mjOBJ_MESH, // mesh
mjOBJ_SKIN, // skin
mjOBJ_HFIELD, // heightfield
mjOBJ_TEXTURE, // texture
mjOBJ_MATERIAL, // material for rendering
mjOBJ_PAIR, // geom pair to include
mjOBJ_EXCLUDE, // body pair to exclude
mjOBJ_EQUALITY, // equality constraint
mjOBJ_TENDON, // tendon
mjOBJ_ACTUATOR, // actuator
mjOBJ_SENSOR, // sensor
mjOBJ_NUMERIC, // numeric
mjOBJ_TEXT, // text
mjOBJ_TUPLE, // tuple
mjOBJ_KEY, // keyframe
mjOBJ_PLUGIN, // plugin instance
mjNOBJECT, // number of object types
// meta elements, do not appear in mjModel
mjOBJ_FRAME = 100 // frame
} mjtObj;
typedef enum mjtConstraint_ { // type of constraint
mjCNSTR_EQUALITY = 0, // equality constraint
mjCNSTR_FRICTION_DOF, // dof friction
mjCNSTR_FRICTION_TENDON, // tendon friction
mjCNSTR_LIMIT_JOINT, // joint limit
mjCNSTR_LIMIT_TENDON, // tendon limit
mjCNSTR_CONTACT_FRICTIONLESS, // frictionless contact
mjCNSTR_CONTACT_PYRAMIDAL, // frictional contact, pyramidal friction cone
mjCNSTR_CONTACT_ELLIPTIC // frictional contact, elliptic friction cone
} mjtConstraint;
typedef enum mjtConstraintState_ { // constraint state
mjCNSTRSTATE_SATISFIED = 0, // constraint satisfied, zero cost (limit, contact)
mjCNSTRSTATE_QUADRATIC, // quadratic cost (equality, friction, limit, contact)
mjCNSTRSTATE_LINEARNEG, // linear cost, negative side (friction)
mjCNSTRSTATE_LINEARPOS, // linear cost, positive side (friction)
mjCNSTRSTATE_CONE // squared distance to cone cost (elliptic contact)
} mjtConstraintState;
typedef enum mjtSensor_ { // type of sensor
// common robotic sensors, attached to a site
mjSENS_TOUCH = 0, // scalar contact normal forces summed over sensor zone
mjSENS_ACCELEROMETER, // 3D linear acceleration, in local frame
mjSENS_VELOCIMETER, // 3D linear velocity, in local frame
mjSENS_GYRO, // 3D angular velocity, in local frame
mjSENS_FORCE, // 3D force between site's body and its parent body
mjSENS_TORQUE, // 3D torque between site's body and its parent body
mjSENS_MAGNETOMETER, // 3D magnetometer
mjSENS_RANGEFINDER, // scalar distance to nearest geom or site along z-axis
mjSENS_CAMPROJECTION, // pixel coordinates of a site in the camera image
// sensors related to scalar joints, tendons, actuators
mjSENS_JOINTPOS, // scalar joint position (hinge and slide only)
mjSENS_JOINTVEL, // scalar joint velocity (hinge and slide only)
mjSENS_TENDONPOS, // scalar tendon position
mjSENS_TENDONVEL, // scalar tendon velocity
mjSENS_ACTUATORPOS, // scalar actuator position
mjSENS_ACTUATORVEL, // scalar actuator velocity
mjSENS_ACTUATORFRC, // scalar actuator force
mjSENS_JOINTACTFRC, // scalar actuator force, measured at the joint
// sensors related to ball joints
mjSENS_BALLQUAT, // 4D ball joint quaternion
mjSENS_BALLANGVEL, // 3D ball joint angular velocity
// joint and tendon limit sensors, in constraint space
mjSENS_JOINTLIMITPOS, // joint limit distance-margin
mjSENS_JOINTLIMITVEL, // joint limit velocity
mjSENS_JOINTLIMITFRC, // joint limit force
mjSENS_TENDONLIMITPOS, // tendon limit distance-margin
mjSENS_TENDONLIMITVEL, // tendon limit velocity
mjSENS_TENDONLIMITFRC, // tendon limit force
// sensors attached to an object with spatial frame: (x)body, geom, site, camera
mjSENS_FRAMEPOS, // 3D position
mjSENS_FRAMEQUAT, // 4D unit quaternion orientation
mjSENS_FRAMEXAXIS, // 3D unit vector: x-axis of object's frame
mjSENS_FRAMEYAXIS, // 3D unit vector: y-axis of object's frame
mjSENS_FRAMEZAXIS, // 3D unit vector: z-axis of object's frame
mjSENS_FRAMELINVEL, // 3D linear velocity
mjSENS_FRAMEANGVEL, // 3D angular velocity
mjSENS_FRAMELINACC, // 3D linear acceleration
mjSENS_FRAMEANGACC, // 3D angular acceleration
// sensors related to kinematic subtrees; attached to a body (which is the subtree root)
mjSENS_SUBTREECOM, // 3D center of mass of subtree
mjSENS_SUBTREELINVEL, // 3D linear velocity of subtree
mjSENS_SUBTREEANGMOM, // 3D angular momentum of subtree
// sensors for geometric distance; attached to geoms or bodies
mjSENS_GEOMDIST, // signed distance between two geoms
mjSENS_GEOMNORMAL, // normal direction between two geoms
mjSENS_GEOMFROMTO, // segment between two geoms
// global sensors
mjSENS_CLOCK, // simulation time
// plugin-controlled sensors
mjSENS_PLUGIN, // plugin-controlled
// user-defined sensor
mjSENS_USER // sensor data provided by mjcb_sensor callback
} mjtSensor;
typedef enum mjtStage_ { // computation stage
mjSTAGE_NONE = 0, // no computations
mjSTAGE_POS, // position-dependent computations
mjSTAGE_VEL, // velocity-dependent computations
mjSTAGE_ACC // acceleration/force-dependent computations
} mjtStage;
typedef enum mjtDataType_ { // data type for sensors
mjDATATYPE_REAL = 0, // real values, no constraints
mjDATATYPE_POSITIVE, // positive values; 0 or negative: inactive
mjDATATYPE_AXIS, // 3D unit vector
mjDATATYPE_QUATERNION // unit quaternion
} mjtDataType;
typedef enum mjtSameFrame_ { // frame alignment of bodies with their children
mjSAMEFRAME_NONE = 0, // no alignment
mjSAMEFRAME_BODY, // frame is same as body frame
mjSAMEFRAME_INERTIA, // frame is same as inertial frame
mjSAMEFRAME_BODYROT, // frame orientation is same as body orientation
mjSAMEFRAME_INERTIAROT // frame orientation is same as inertia orientation
} mjtSameFrame;
typedef enum mjtLRMode_ { // mode for actuator length range computation
mjLRMODE_NONE = 0, // do not process any actuators
mjLRMODE_MUSCLE, // process muscle actuators
mjLRMODE_MUSCLEUSER, // process muscle and user actuators
mjLRMODE_ALL // process all actuators
} mjtLRMode;
typedef enum mjtFlexSelf_ { // mode for flex selfcollide
mjFLEXSELF_NONE = 0, // no self-collisions
mjFLEXSELF_NARROW, // skip midphase, go directly to narrowphase
mjFLEXSELF_BVH, // use BVH in midphase (if midphase enabled)
mjFLEXSELF_SAP, // use SAP in midphase
mjFLEXSELF_AUTO // choose between BVH and SAP automatically
} mjtFlexSelf;
//---------------------------------- mjLROpt -------------------------------------------------------
struct mjLROpt_ { // options for mj_setLengthRange()
// flags
int mode; // which actuators to process (mjtLRMode)
int useexisting; // use existing length range if available
int uselimit; // use joint and tendon limits if available
// algorithm parameters
mjtNum accel; // target acceleration used to compute force
mjtNum maxforce; // maximum force; 0: no limit
mjtNum timeconst; // time constant for velocity reduction; min 0.01
mjtNum timestep; // simulation timestep; 0: use mjOption.timestep
mjtNum inttotal; // total simulation time interval
mjtNum interval; // evaluation time interval (at the end)
mjtNum tolrange; // convergence tolerance (relative to range)
};
typedef struct mjLROpt_ mjLROpt;
//---------------------------------- mjVFS ---------------------------------------------------------
struct mjVFS_ { // virtual file system for loading from memory
void* impl_; // internal pointer to VFS memory
};
typedef struct mjVFS_ mjVFS;
//---------------------------------- mjOption ------------------------------------------------------
struct mjOption_ { // physics options
// timing parameters
mjtNum timestep; // timestep
mjtNum apirate; // update rate for remote API (Hz)
// solver parameters
mjtNum impratio; // ratio of friction-to-normal contact impedance
mjtNum tolerance; // main solver tolerance
mjtNum ls_tolerance; // CG/Newton linesearch tolerance
mjtNum noslip_tolerance; // noslip solver tolerance
mjtNum ccd_tolerance; // convex collision solver tolerance
// physical constants
mjtNum gravity[3]; // gravitational acceleration
mjtNum wind[3]; // wind (for lift, drag and viscosity)
mjtNum magnetic[3]; // global magnetic flux
mjtNum density; // density of medium
mjtNum viscosity; // viscosity of medium
// override contact solver parameters (if enabled)
mjtNum o_margin; // margin
mjtNum o_solref[mjNREF]; // solref
mjtNum o_solimp[mjNIMP]; // solimp
mjtNum o_friction[5]; // friction
// discrete settings
int integrator; // integration mode (mjtIntegrator)
int cone; // type of friction cone (mjtCone)
int jacobian; // type of Jacobian (mjtJacobian)
int solver; // solver algorithm (mjtSolver)
int iterations; // maximum number of main solver iterations
int ls_iterations; // maximum number of CG/Newton linesearch iterations
int noslip_iterations; // maximum number of noslip solver iterations
int ccd_iterations; // maximum number of convex collision solver iterations
int disableflags; // bit flags for disabling standard features
int enableflags; // bit flags for enabling optional features
int disableactuator; // bit flags for disabling actuators by group id
// sdf collision settings
int sdf_initpoints; // number of starting points for gradient descent
int sdf_iterations; // max number of iterations for gradient descent
};
typedef struct mjOption_ mjOption;
//---------------------------------- mjVisual ------------------------------------------------------
struct mjVisual_ { // visualization options
struct { // global parameters
int orthographic; // is the free camera orthographic (0: no, 1: yes)
float fovy; // y field-of-view of free camera (orthographic ? length : degree)
float ipd; // inter-pupilary distance for free camera
float azimuth; // initial azimuth of free camera (degrees)
float elevation; // initial elevation of free camera (degrees)
float linewidth; // line width for wireframe and ray rendering
float glow; // glow coefficient for selected body
float realtime; // initial real-time factor (1: real time)
int offwidth; // width of offscreen buffer
int offheight; // height of offscreen buffer
int ellipsoidinertia; // geom for inertia visualization (0: box, 1: ellipsoid)
int bvactive; // visualize active bounding volumes (0: no, 1: yes)
} global;
struct { // rendering quality
int shadowsize; // size of shadowmap texture
int offsamples; // number of multisamples for offscreen rendering
int numslices; // number of slices for builtin geom drawing
int numstacks; // number of stacks for builtin geom drawing
int numquads; // number of quads for box rendering
} quality;
struct { // head light
float ambient[3]; // ambient rgb (alpha=1)
float diffuse[3]; // diffuse rgb (alpha=1)
float specular[3]; // specular rgb (alpha=1)
int active; // is headlight active
} headlight;
struct { // mapping
float stiffness; // mouse perturbation stiffness (space->force)
float stiffnessrot; // mouse perturbation stiffness (space->torque)
float force; // from force units to space units
float torque; // from torque units to space units
float alpha; // scale geom alphas when transparency is enabled
float fogstart; // OpenGL fog starts at fogstart * mjModel.stat.extent
float fogend; // OpenGL fog ends at fogend * mjModel.stat.extent
float znear; // near clipping plane = znear * mjModel.stat.extent
float zfar; // far clipping plane = zfar * mjModel.stat.extent
float haze; // haze ratio
float shadowclip; // directional light: shadowclip * mjModel.stat.extent
float shadowscale; // spot light: shadowscale * light.cutoff
float actuatortendon; // scale tendon width
} map;
struct { // scale of decor elements relative to mean body size
float forcewidth; // width of force arrow
float contactwidth; // contact width
float contactheight; // contact height
float connect; // autoconnect capsule width
float com; // com radius
float camera; // camera object
float light; // light object
float selectpoint; // selection point
float jointlength; // joint length
float jointwidth; // joint width
float actuatorlength; // actuator length
float actuatorwidth; // actuator width
float framelength; // bodyframe axis length
float framewidth; // bodyframe axis width
float constraint; // constraint width
float slidercrank; // slidercrank width
float frustum; // frustum zfar plane
} scale;
struct { // color of decor elements
float fog[4]; // fog
float haze[4]; // haze
float force[4]; // external force
float inertia[4]; // inertia box
float joint[4]; // joint
float actuator[4]; // actuator, neutral
float actuatornegative[4]; // actuator, negative limit
float actuatorpositive[4]; // actuator, positive limit
float com[4]; // center of mass
float camera[4]; // camera object
float light[4]; // light object
float selectpoint[4]; // selection point
float connect[4]; // auto connect
float contactpoint[4]; // contact point
float contactforce[4]; // contact force
float contactfriction[4]; // contact friction force
float contacttorque[4]; // contact torque
float contactgap[4]; // contact point in gap
float rangefinder[4]; // rangefinder ray
float constraint[4]; // constraint
float slidercrank[4]; // slidercrank
float crankbroken[4]; // used when crank must be stretched/broken
float frustum[4]; // camera frustum
float bv[4]; // bounding volume
float bvactive[4]; // active bounding volume
} rgba;
};
typedef struct mjVisual_ mjVisual;
//---------------------------------- mjStatistic ---------------------------------------------------
struct mjStatistic_ { // model statistics (in qpos0)
mjtNum meaninertia; // mean diagonal inertia
mjtNum meanmass; // mean body mass
mjtNum meansize; // mean body size
mjtNum extent; // spatial extent
mjtNum center[3]; // center of model
};
typedef struct mjStatistic_ mjStatistic;
//---------------------------------- mjModel -------------------------------------------------------
struct mjModel_ {
// ------------------------------- sizes
// sizes needed at mjModel construction
int nq; // number of generalized coordinates = dim(qpos)
int nv; // number of degrees of freedom = dim(qvel)
int nu; // number of actuators/controls = dim(ctrl)
int na; // number of activation states = dim(act)
int nbody; // number of bodies
int nbvh; // number of total bounding volumes in all bodies
int nbvhstatic; // number of static bounding volumes (aabb stored in mjModel)
int nbvhdynamic; // number of dynamic bounding volumes (aabb stored in mjData)
int njnt; // number of joints
int ngeom; // number of geoms
int nsite; // number of sites
int ncam; // number of cameras
int nlight; // number of lights
int nflex; // number of flexes
int nflexvert; // number of vertices in all flexes
int nflexedge; // number of edges in all flexes
int nflexelem; // number of elements in all flexes
int nflexelemdata; // number of element vertex ids in all flexes
int nflexelemedge; // number of element edge ids in all flexes
int nflexshelldata; // number of shell fragment vertex ids in all flexes
int nflexevpair; // number of element-vertex pairs in all flexes
int nflextexcoord; // number of vertices with texture coordinates
int nmesh; // number of meshes
int nmeshvert; // number of vertices in all meshes
int nmeshnormal; // number of normals in all meshes
int nmeshtexcoord; // number of texcoords in all meshes
int nmeshface; // number of triangular faces in all meshes
int nmeshgraph; // number of ints in mesh auxiliary data
int nskin; // number of skins
int nskinvert; // number of vertices in all skins
int nskintexvert; // number of vertiex with texcoords in all skins
int nskinface; // number of triangular faces in all skins
int nskinbone; // number of bones in all skins
int nskinbonevert; // number of vertices in all skin bones
int nhfield; // number of heightfields
int nhfielddata; // number of data points in all heightfields
int ntex; // number of textures
int ntexdata; // number of bytes in texture rgb data
int nmat; // number of materials
int npair; // number of predefined geom pairs
int nexclude; // number of excluded geom pairs
int neq; // number of equality constraints
int ntendon; // number of tendons
int nwrap; // number of wrap objects in all tendon paths
int nsensor; // number of sensors
int nnumeric; // number of numeric custom fields
int nnumericdata; // number of mjtNums in all numeric fields
int ntext; // number of text custom fields
int ntextdata; // number of mjtBytes in all text fields
int ntuple; // number of tuple custom fields
int ntupledata; // number of objects in all tuple fields
int nkey; // number of keyframes
int nmocap; // number of mocap bodies
int nplugin; // number of plugin instances
int npluginattr; // number of chars in all plugin config attributes
int nuser_body; // number of mjtNums in body_user
int nuser_jnt; // number of mjtNums in jnt_user
int nuser_geom; // number of mjtNums in geom_user
int nuser_site; // number of mjtNums in site_user
int nuser_cam; // number of mjtNums in cam_user
int nuser_tendon; // number of mjtNums in tendon_user
int nuser_actuator; // number of mjtNums in actuator_user
int nuser_sensor; // number of mjtNums in sensor_user
int nnames; // number of chars in all names
int npaths; // number of chars in all paths
// sizes set after mjModel construction
int nnames_map; // number of slots in the names hash map
int nM; // number of non-zeros in sparse inertia matrix
int nB; // number of non-zeros in sparse body-dof matrix
int nC; // number of non-zeros in sparse reduced dof-dof matrix
int nD; // number of non-zeros in sparse dof-dof matrix
int nJmom; // number of non-zeros in sparse actuator_moment matrix
int ntree; // number of kinematic trees under world body
int ngravcomp; // number of bodies with nonzero gravcomp
int nemax; // number of potential equality-constraint rows
int njmax; // number of available rows in constraint Jacobian (legacy)
int nconmax; // number of potential contacts in contact list (legacy)
int nuserdata; // number of mjtNums reserved for the user
int nsensordata; // number of mjtNums in sensor data vector
int npluginstate; // number of mjtNums in plugin state vector
size_t narena; // number of bytes in the mjData arena (inclusive of stack)
size_t nbuffer; // number of bytes in buffer
// ------------------------------- options and statistics
mjOption opt; // physics options
mjVisual vis; // visualization options
mjStatistic stat; // model statistics
// ------------------------------- buffers
// main buffer
void* buffer; // main buffer; all pointers point in it (nbuffer)
// default generalized coordinates
mjtNum* qpos0; // qpos values at default pose (nq x 1)
mjtNum* qpos_spring; // reference pose for springs (nq x 1)
// bodies
int* body_parentid; // id of body's parent (nbody x 1)
int* body_rootid; // id of root above body (nbody x 1)
int* body_weldid; // id of body that this body is welded to (nbody x 1)
int* body_mocapid; // id of mocap data; -1: none (nbody x 1)
int* body_jntnum; // number of joints for this body (nbody x 1)
int* body_jntadr; // start addr of joints; -1: no joints (nbody x 1)
int* body_dofnum; // number of motion degrees of freedom (nbody x 1)
int* body_dofadr; // start addr of dofs; -1: no dofs (nbody x 1)
int* body_treeid; // id of body's kinematic tree; -1: static (nbody x 1)
int* body_geomnum; // number of geoms (nbody x 1)
int* body_geomadr; // start addr of geoms; -1: no geoms (nbody x 1)
mjtByte* body_simple; // 1: diag M; 2: diag M, sliders only (nbody x 1)
mjtByte* body_sameframe; // same frame as inertia (mjtSameframe) (nbody x 1)
mjtNum* body_pos; // position offset rel. to parent body (nbody x 3)
mjtNum* body_quat; // orientation offset rel. to parent body (nbody x 4)
mjtNum* body_ipos; // local position of center of mass (nbody x 3)
mjtNum* body_iquat; // local orientation of inertia ellipsoid (nbody x 4)
mjtNum* body_mass; // mass (nbody x 1)
mjtNum* body_subtreemass; // mass of subtree starting at this body (nbody x 1)
mjtNum* body_inertia; // diagonal inertia in ipos/iquat frame (nbody x 3)
mjtNum* body_invweight0; // mean inv inert in qpos0 (trn, rot) (nbody x 2)
mjtNum* body_gravcomp; // antigravity force, units of body weight (nbody x 1)
mjtNum* body_margin; // MAX over all geom margins (nbody x 1)
mjtNum* body_user; // user data (nbody x nuser_body)
int* body_plugin; // plugin instance id; -1: not in use (nbody x 1)
int* body_contype; // OR over all geom contypes (nbody x 1)
int* body_conaffinity; // OR over all geom conaffinities (nbody x 1)
int* body_bvhadr; // address of bvh root (nbody x 1)
int* body_bvhnum; // number of bounding volumes (nbody x 1)
// bounding volume hierarchy
int* bvh_depth; // depth in the bounding volume hierarchy (nbvh x 1)
int* bvh_child; // left and right children in tree (nbvh x 2)
int* bvh_nodeid; // geom or elem id of node; -1: non-leaf (nbvh x 1)
mjtNum* bvh_aabb; // local bounding box (center, size) (nbvhstatic x 6)
// joints
int* jnt_type; // type of joint (mjtJoint) (njnt x 1)
int* jnt_qposadr; // start addr in 'qpos' for joint's data (njnt x 1)
int* jnt_dofadr; // start addr in 'qvel' for joint's data (njnt x 1)
int* jnt_bodyid; // id of joint's body (njnt x 1)
int* jnt_group; // group for visibility (njnt x 1)
mjtByte* jnt_limited; // does joint have limits (njnt x 1)
mjtByte* jnt_actfrclimited; // does joint have actuator force limits (njnt x 1)
mjtByte* jnt_actgravcomp; // is gravcomp force applied via actuators (njnt x 1)
mjtNum* jnt_solref; // constraint solver reference: limit (njnt x mjNREF)
mjtNum* jnt_solimp; // constraint solver impedance: limit (njnt x mjNIMP)
mjtNum* jnt_pos; // local anchor position (njnt x 3)
mjtNum* jnt_axis; // local joint axis (njnt x 3)
mjtNum* jnt_stiffness; // stiffness coefficient (njnt x 1)
mjtNum* jnt_range; // joint limits (njnt x 2)
mjtNum* jnt_actfrcrange; // range of total actuator force (njnt x 2)
mjtNum* jnt_margin; // min distance for limit detection (njnt x 1)
mjtNum* jnt_user; // user data (njnt x nuser_jnt)
// dofs
int* dof_bodyid; // id of dof's body (nv x 1)
int* dof_jntid; // id of dof's joint (nv x 1)
int* dof_parentid; // id of dof's parent; -1: none (nv x 1)
int* dof_treeid; // id of dof's kinematic tree (nv x 1)
int* dof_Madr; // dof address in M-diagonal (nv x 1)
int* dof_simplenum; // number of consecutive simple dofs (nv x 1)
mjtNum* dof_solref; // constraint solver reference:frictionloss (nv x mjNREF)
mjtNum* dof_solimp; // constraint solver impedance:frictionloss (nv x mjNIMP)
mjtNum* dof_frictionloss; // dof friction loss (nv x 1)
mjtNum* dof_armature; // dof armature inertia/mass (nv x 1)
mjtNum* dof_damping; // damping coefficient (nv x 1)
mjtNum* dof_invweight0; // diag. inverse inertia in qpos0 (nv x 1)
mjtNum* dof_M0; // diag. inertia in qpos0 (nv x 1)
// geoms
int* geom_type; // geometric type (mjtGeom) (ngeom x 1)
int* geom_contype; // geom contact type (ngeom x 1)
int* geom_conaffinity; // geom contact affinity (ngeom x 1)
int* geom_condim; // contact dimensionality (1, 3, 4, 6) (ngeom x 1)
int* geom_bodyid; // id of geom's body (ngeom x 1)
int* geom_dataid; // id of geom's mesh/hfield; -1: none (ngeom x 1)
int* geom_matid; // material id for rendering; -1: none (ngeom x 1)
int* geom_group; // group for visibility (ngeom x 1)
int* geom_priority; // geom contact priority (ngeom x 1)
int* geom_plugin; // plugin instance id; -1: not in use (ngeom x 1)
mjtByte* geom_sameframe; // same frame as body (mjtSameframe) (ngeom x 1)
mjtNum* geom_solmix; // mixing coef for solref/imp in geom pair (ngeom x 1)
mjtNum* geom_solref; // constraint solver reference: contact (ngeom x mjNREF)
mjtNum* geom_solimp; // constraint solver impedance: contact (ngeom x mjNIMP)
mjtNum* geom_size; // geom-specific size parameters (ngeom x 3)
mjtNum* geom_aabb; // bounding box, (center, size) (ngeom x 6)
mjtNum* geom_rbound; // radius of bounding sphere (ngeom x 1)
mjtNum* geom_pos; // local position offset rel. to body (ngeom x 3)
mjtNum* geom_spos; // spec local position offset rel. to body (ngeom x 3)
mjtNum* geom_quat; // local orientation offset rel. to body (ngeom x 4)
mjtNum* geom_squat; // spec local orientation offset rel. body (ngeom x 4)
mjtNum* geom_friction; // friction for (slide, spin, roll) (ngeom x 3)
mjtNum* geom_margin; // detect contact if dist<margin (ngeom x 1)
mjtNum* geom_gap; // include in solver if dist<margin-gap (ngeom x 1)
mjtNum* geom_fluid; // fluid interaction parameters (ngeom x mjNFLUID)
mjtNum* geom_user; // user data (ngeom x nuser_geom)
float* geom_rgba; // rgba when material is omitted (ngeom x 4)
// sites
int* site_type; // geom type for rendering (mjtGeom) (nsite x 1)
int* site_bodyid; // id of site's body (nsite x 1)
int* site_matid; // material id for rendering; -1: none (nsite x 1)
int* site_group; // group for visibility (nsite x 1)
mjtByte* site_sameframe; // same frame as body (mjtSameframe) (nsite x 1)
mjtNum* site_size; // geom size for rendering (nsite x 3)
mjtNum* site_pos; // local position offset rel. to body (nsite x 3)
mjtNum* site_quat; // local orientation offset rel. to body (nsite x 4)
mjtNum* site_user; // user data (nsite x nuser_site)
float* site_rgba; // rgba when material is omitted (nsite x 4)
// cameras
int* cam_mode; // camera tracking mode (mjtCamLight) (ncam x 1)
int* cam_bodyid; // id of camera's body (ncam x 1)
int* cam_targetbodyid; // id of targeted body; -1: none (ncam x 1)
mjtNum* cam_pos; // position rel. to body frame (ncam x 3)
mjtNum* cam_quat; // orientation rel. to body frame (ncam x 4)
mjtNum* cam_poscom0; // global position rel. to sub-com in qpos0 (ncam x 3)
mjtNum* cam_pos0; // global position rel. to body in qpos0 (ncam x 3)
mjtNum* cam_mat0; // global orientation in qpos0 (ncam x 9)
int* cam_orthographic; // orthographic camera; 0: no, 1: yes (ncam x 1)
mjtNum* cam_fovy; // y field-of-view (ortho ? len : deg) (ncam x 1)
mjtNum* cam_ipd; // inter-pupilary distance (ncam x 1)
int* cam_resolution; // resolution: pixels [width, height] (ncam x 2)
float* cam_sensorsize; // sensor size: length [width, height] (ncam x 2)
float* cam_intrinsic; // [focal length; principal point] (ncam x 4)
mjtNum* cam_user; // user data (ncam x nuser_cam)
// lights
int* light_mode; // light tracking mode (mjtCamLight) (nlight x 1)
int* light_bodyid; // id of light's body (nlight x 1)
int* light_targetbodyid; // id of targeted body; -1: none (nlight x 1)
mjtByte* light_directional; // directional light (nlight x 1)
mjtByte* light_castshadow; // does light cast shadows (nlight x 1)
float* light_bulbradius; // light radius for soft shadows (nlight x 1)
mjtByte* light_active; // is light on (nlight x 1)
mjtNum* light_pos; // position rel. to body frame (nlight x 3)
mjtNum* light_dir; // direction rel. to body frame (nlight x 3)
mjtNum* light_poscom0; // global position rel. to sub-com in qpos0 (nlight x 3)
mjtNum* light_pos0; // global position rel. to body in qpos0 (nlight x 3)
mjtNum* light_dir0; // global direction in qpos0 (nlight x 3)
float* light_attenuation; // OpenGL attenuation (quadratic model) (nlight x 3)
float* light_cutoff; // OpenGL cutoff (nlight x 1)
float* light_exponent; // OpenGL exponent (nlight x 1)
float* light_ambient; // ambient rgb (alpha=1) (nlight x 3)
float* light_diffuse; // diffuse rgb (alpha=1) (nlight x 3)
float* light_specular; // specular rgb (alpha=1) (nlight x 3)
// flexes: contact properties
int* flex_contype; // flex contact type (nflex x 1)
int* flex_conaffinity; // flex contact affinity (nflex x 1)
int* flex_condim; // contact dimensionality (1, 3, 4, 6) (nflex x 1)
int* flex_priority; // flex contact priority (nflex x 1)
mjtNum* flex_solmix; // mix coef for solref/imp in contact pair (nflex x 1)
mjtNum* flex_solref; // constraint solver reference: contact (nflex x mjNREF)
mjtNum* flex_solimp; // constraint solver impedance: contact (nflex x mjNIMP)
mjtNum* flex_friction; // friction for (slide, spin, roll) (nflex x 3)
mjtNum* flex_margin; // detect contact if dist<margin (nflex x 1)
mjtNum* flex_gap; // include in solver if dist<margin-gap (nflex x 1)
mjtByte* flex_internal; // internal flex collision enabled (nflex x 1)
int* flex_selfcollide; // self collision mode (mjtFlexSelf) (nflex x 1)
int* flex_activelayers; // number of active element layers, 3D only (nflex x 1)
// flexes: other properties
int* flex_dim; // 1: lines, 2: triangles, 3: tetrahedra (nflex x 1)
int* flex_matid; // material id for rendering (nflex x 1)
int* flex_group; // group for visibility (nflex x 1)
int* flex_vertadr; // first vertex address (nflex x 1)
int* flex_vertnum; // number of vertices (nflex x 1)
int* flex_edgeadr; // first edge address (nflex x 1)
int* flex_edgenum; // number of edges (nflex x 1)
int* flex_elemadr; // first element address (nflex x 1)
int* flex_elemnum; // number of elements (nflex x 1)
int* flex_elemdataadr; // first element vertex id address (nflex x 1)
int* flex_elemedgeadr; // first element edge id address (nflex x 1)
int* flex_shellnum; // number of shells (nflex x 1)
int* flex_shelldataadr; // first shell data address (nflex x 1)
int* flex_evpairadr; // first evpair address (nflex x 1)
int* flex_evpairnum; // number of evpairs (nflex x 1)
int* flex_texcoordadr; // address in flex_texcoord; -1: none (nflex x 1)
int* flex_vertbodyid; // vertex body ids (nflexvert x 1)
int* flex_edge; // edge vertex ids (2 per edge) (nflexedge x 2)
int* flex_elem; // element vertex ids (dim+1 per elem) (nflexelemdata x 1)
int* flex_elemedge; // element edge ids (nflexelemedge x 1)
int* flex_elemlayer; // element distance from surface, 3D only (nflexelem x 1)
int* flex_shell; // shell fragment vertex ids (dim per frag) (nflexshelldata x 1)
int* flex_evpair; // (element, vertex) collision pairs (nflexevpair x 2)
mjtNum* flex_vert; // vertex positions in local body frames (nflexvert x 3)
mjtNum* flex_vert0; // vertex positions in qpos0 on [0, 1]^d (nflexvert x 3)
mjtNum* flexedge_length0; // edge lengths in qpos0 (nflexedge x 1)
mjtNum* flexedge_invweight0; // edge inv. weight in qpos0 (nflexedge x 1)
mjtNum* flex_radius; // radius around primitive element (nflex x 1)
mjtNum* flex_stiffness; // finite element stiffness matrix (nflexelem x 21)
mjtNum* flex_damping; // Rayleigh's damping coefficient (nflex x 1)
mjtNum* flex_edgestiffness; // edge stiffness (nflex x 1)
mjtNum* flex_edgedamping; // edge damping (nflex x 1)
mjtByte* flex_edgeequality; // is edge equality constraint defined (nflex x 1)
mjtByte* flex_rigid; // are all verices in the same body (nflex x 1)
mjtByte* flexedge_rigid; // are both edge vertices in same body (nflexedge x 1)
mjtByte* flex_centered; // are all vertex coordinates (0,0,0) (nflex x 1)
mjtByte* flex_flatskin; // render flex skin with flat shading (nflex x 1)
int* flex_bvhadr; // address of bvh root; -1: no bvh (nflex x 1)
int* flex_bvhnum; // number of bounding volumes (nflex x 1)
float* flex_rgba; // rgba when material is omitted (nflex x 4)
float* flex_texcoord; // vertex texture coordinates (nflextexcoord x 2)
// meshes
int* mesh_vertadr; // first vertex address (nmesh x 1)
int* mesh_vertnum; // number of vertices (nmesh x 1)
int* mesh_faceadr; // first face address (nmesh x 1)
int* mesh_facenum; // number of faces (nmesh x 1)
int* mesh_bvhadr; // address of bvh root (nmesh x 1)
int* mesh_bvhnum; // number of bvh (nmesh x 1)
int* mesh_normaladr; // first normal address (nmesh x 1)
int* mesh_normalnum; // number of normals (nmesh x 1)
int* mesh_texcoordadr; // texcoord data address; -1: no texcoord (nmesh x 1)
int* mesh_texcoordnum; // number of texcoord (nmesh x 1)
int* mesh_graphadr; // graph data address; -1: no graph (nmesh x 1)
float* mesh_vert; // vertex positions for all meshes (nmeshvert x 3)
float* mesh_normal; // normals for all meshes (nmeshnormal x 3)
float* mesh_texcoord; // vertex texcoords for all meshes (nmeshtexcoord x 2)
int* mesh_face; // vertex face data (nmeshface x 3)
int* mesh_facenormal; // normal face data (nmeshface x 3)
int* mesh_facetexcoord; // texture face data (nmeshface x 3)
int* mesh_graph; // convex graph data (nmeshgraph x 1)
mjtNum* mesh_scale; // scaling applied to asset vertices (nmesh x 3)
mjtNum* mesh_pos; // translation applied to asset vertices (nmesh x 3)
mjtNum* mesh_quat; // rotation applied to asset vertices (nmesh x 4)
int* mesh_pathadr; // address of asset path for mesh; -1: none (nmesh x 1)
// skins
int* skin_matid; // skin material id; -1: none (nskin x 1)
int* skin_group; // group for visibility (nskin x 1)
float* skin_rgba; // skin rgba (nskin x 4)
float* skin_inflate; // inflate skin in normal direction (nskin x 1)
int* skin_vertadr; // first vertex address (nskin x 1)
int* skin_vertnum; // number of vertices (nskin x 1)
int* skin_texcoordadr; // texcoord data address; -1: no texcoord (nskin x 1)
int* skin_faceadr; // first face address (nskin x 1)
int* skin_facenum; // number of faces (nskin x 1)
int* skin_boneadr; // first bone in skin (nskin x 1)
int* skin_bonenum; // number of bones in skin (nskin x 1)
float* skin_vert; // vertex positions for all skin meshes (nskinvert x 3)
float* skin_texcoord; // vertex texcoords for all skin meshes (nskintexvert x 2)
int* skin_face; // triangle faces for all skin meshes (nskinface x 3)
int* skin_bonevertadr; // first vertex in each bone (nskinbone x 1)
int* skin_bonevertnum; // number of vertices in each bone (nskinbone x 1)
float* skin_bonebindpos; // bind pos of each bone (nskinbone x 3)
float* skin_bonebindquat; // bind quat of each bone (nskinbone x 4)
int* skin_bonebodyid; // body id of each bone (nskinbone x 1)
int* skin_bonevertid; // mesh ids of vertices in each bone (nskinbonevert x 1)
float* skin_bonevertweight; // weights of vertices in each bone (nskinbonevert x 1)
int* skin_pathadr; // address of asset path for skin; -1: none (nskin x 1)
// height fields
mjtNum* hfield_size; // (x, y, z_top, z_bottom) (nhfield x 4)
int* hfield_nrow; // number of rows in grid (nhfield x 1)
int* hfield_ncol; // number of columns in grid (nhfield x 1)
int* hfield_adr; // address in hfield_data (nhfield x 1)
float* hfield_data; // elevation data (nhfielddata x 1)
int* hfield_pathadr; // address of hfield asset path; -1: none (nhfield x 1)
// textures
int* tex_type; // texture type (mjtTexture) (ntex x 1)
int* tex_height; // number of rows in texture image (ntex x 1)
int* tex_width; // number of columns in texture image (ntex x 1)
int* tex_nchannel; // number of channels in texture image (ntex x 1)
int* tex_adr; // start address in tex_data (ntex x 1)
mjtByte* tex_data; // pixel values (ntexdata x 1)
int* tex_pathadr; // address of texture asset path; -1: none (ntex x 1)
// materials
int* mat_texid; // indices of textures; -1: none (nmat x mjNTEXROLE)
mjtByte* mat_texuniform; // make texture cube uniform (nmat x 1)
float* mat_texrepeat; // texture repetition for 2d mapping (nmat x 2)
float* mat_emission; // emission (x rgb) (nmat x 1)
float* mat_specular; // specular (x white) (nmat x 1)
float* mat_shininess; // shininess coef (nmat x 1)
float* mat_reflectance; // reflectance (0: disable) (nmat x 1)
float* mat_metallic; // metallic coef (nmat x 1)
float* mat_roughness; // roughness coef (nmat x 1)
float* mat_rgba; // rgba (nmat x 4)
// predefined geom pairs for collision detection; has precedence over exclude
int* pair_dim; // contact dimensionality (npair x 1)
int* pair_geom1; // id of geom1 (npair x 1)
int* pair_geom2; // id of geom2 (npair x 1)
int* pair_signature; // body1 << 16 + body2 (npair x 1)
mjtNum* pair_solref; // solver reference: contact normal (npair x mjNREF)
mjtNum* pair_solreffriction; // solver reference: contact friction (npair x mjNREF)
mjtNum* pair_solimp; // solver impedance: contact (npair x mjNIMP)
mjtNum* pair_margin; // detect contact if dist<margin (npair x 1)
mjtNum* pair_gap; // include in solver if dist<margin-gap (npair x 1)
mjtNum* pair_friction; // tangent1, 2, spin, roll1, 2 (npair x 5)
// excluded body pairs for collision detection
int* exclude_signature; // body1 << 16 + body2 (nexclude x 1)
// equality constraints
int* eq_type; // constraint type (mjtEq) (neq x 1)
int* eq_obj1id; // id of object 1 (neq x 1)
int* eq_obj2id; // id of object 2 (neq x 1)
int* eq_objtype; // type of both objects (mjtObj) (neq x 1)
mjtByte* eq_active0; // initial enable/disable constraint state (neq x 1)
mjtNum* eq_solref; // constraint solver reference (neq x mjNREF)
mjtNum* eq_solimp; // constraint solver impedance (neq x mjNIMP)
mjtNum* eq_data; // numeric data for constraint (neq x mjNEQDATA)
// tendons
int* tendon_adr; // address of first object in tendon's path (ntendon x 1)
int* tendon_num; // number of objects in tendon's path (ntendon x 1)
int* tendon_matid; // material id for rendering (ntendon x 1)
int* tendon_group; // group for visibility (ntendon x 1)
mjtByte* tendon_limited; // does tendon have length limits (ntendon x 1)
mjtNum* tendon_width; // width for rendering (ntendon x 1)
mjtNum* tendon_solref_lim; // constraint solver reference: limit (ntendon x mjNREF)
mjtNum* tendon_solimp_lim; // constraint solver impedance: limit (ntendon x mjNIMP)
mjtNum* tendon_solref_fri; // constraint solver reference: friction (ntendon x mjNREF)
mjtNum* tendon_solimp_fri; // constraint solver impedance: friction (ntendon x mjNIMP)
mjtNum* tendon_range; // tendon length limits (ntendon x 2)
mjtNum* tendon_margin; // min distance for limit detection (ntendon x 1)
mjtNum* tendon_stiffness; // stiffness coefficient (ntendon x 1)
mjtNum* tendon_damping; // damping coefficient (ntendon x 1)
mjtNum* tendon_frictionloss; // loss due to friction (ntendon x 1)
mjtNum* tendon_lengthspring; // spring resting length range (ntendon x 2)
mjtNum* tendon_length0; // tendon length in qpos0 (ntendon x 1)
mjtNum* tendon_invweight0; // inv. weight in qpos0 (ntendon x 1)
mjtNum* tendon_user; // user data (ntendon x nuser_tendon)
float* tendon_rgba; // rgba when material is omitted (ntendon x 4)
// list of all wrap objects in tendon paths
int* wrap_type; // wrap object type (mjtWrap) (nwrap x 1)
int* wrap_objid; // object id: geom, site, joint (nwrap x 1)
mjtNum* wrap_prm; // divisor, joint coef, or site id (nwrap x 1)
// actuators
int* actuator_trntype; // transmission type (mjtTrn) (nu x 1)
int* actuator_dyntype; // dynamics type (mjtDyn) (nu x 1)
int* actuator_gaintype; // gain type (mjtGain) (nu x 1)
int* actuator_biastype; // bias type (mjtBias) (nu x 1)
int* actuator_trnid; // transmission id: joint, tendon, site (nu x 2)
int* actuator_actadr; // first activation address; -1: stateless (nu x 1)
int* actuator_actnum; // number of activation variables (nu x 1)
int* actuator_group; // group for visibility (nu x 1)
mjtByte* actuator_ctrllimited; // is control limited (nu x 1)
mjtByte* actuator_forcelimited;// is force limited (nu x 1)
mjtByte* actuator_actlimited; // is activation limited (nu x 1)
mjtNum* actuator_dynprm; // dynamics parameters (nu x mjNDYN)
mjtNum* actuator_gainprm; // gain parameters (nu x mjNGAIN)
mjtNum* actuator_biasprm; // bias parameters (nu x mjNBIAS)
mjtByte* actuator_actearly; // step activation before force (nu x 1)
mjtNum* actuator_ctrlrange; // range of controls (nu x 2)
mjtNum* actuator_forcerange; // range of forces (nu x 2)
mjtNum* actuator_actrange; // range of activations (nu x 2)
mjtNum* actuator_gear; // scale length and transmitted force (nu x 6)
mjtNum* actuator_cranklength; // crank length for slider-crank (nu x 1)
mjtNum* actuator_acc0; // acceleration from unit force in qpos0 (nu x 1)
mjtNum* actuator_length0; // actuator length in qpos0 (nu x 1)
mjtNum* actuator_lengthrange; // feasible actuator length range (nu x 2)
mjtNum* actuator_user; // user data (nu x nuser_actuator)
int* actuator_plugin; // plugin instance id; -1: not a plugin (nu x 1)
// sensors
int* sensor_type; // sensor type (mjtSensor) (nsensor x 1)
int* sensor_datatype; // numeric data type (mjtDataType) (nsensor x 1)
int* sensor_needstage; // required compute stage (mjtStage) (nsensor x 1)
int* sensor_objtype; // type of sensorized object (mjtObj) (nsensor x 1)
int* sensor_objid; // id of sensorized object (nsensor x 1)
int* sensor_reftype; // type of reference frame (mjtObj) (nsensor x 1)
int* sensor_refid; // id of reference frame; -1: global frame (nsensor x 1)
int* sensor_dim; // number of scalar outputs (nsensor x 1)
int* sensor_adr; // address in sensor array (nsensor x 1)
mjtNum* sensor_cutoff; // cutoff for real and positive; 0: ignore (nsensor x 1)
mjtNum* sensor_noise; // noise standard deviation (nsensor x 1)
mjtNum* sensor_user; // user data (nsensor x nuser_sensor)
int* sensor_plugin; // plugin instance id; -1: not a plugin (nsensor x 1)
// plugin instances
int* plugin; // globally registered plugin slot number (nplugin x 1)
int* plugin_stateadr; // address in the plugin state array (nplugin x 1)
int* plugin_statenum; // number of states in the plugin instance (nplugin x 1)
char* plugin_attr; // config attributes of plugin instances (npluginattr x 1)
int* plugin_attradr; // address to each instance's config attrib (nplugin x 1)
// custom numeric fields
int* numeric_adr; // address of field in numeric_data (nnumeric x 1)
int* numeric_size; // size of numeric field (nnumeric x 1)
mjtNum* numeric_data; // array of all numeric fields (nnumericdata x 1)
// custom text fields
int* text_adr; // address of text in text_data (ntext x 1)
int* text_size; // size of text field (strlen+1) (ntext x 1)
char* text_data; // array of all text fields (0-terminated) (ntextdata x 1)
// custom tuple fields
int* tuple_adr; // address of text in text_data (ntuple x 1)
int* tuple_size; // number of objects in tuple (ntuple x 1)
int* tuple_objtype; // array of object types in all tuples (ntupledata x 1)
int* tuple_objid; // array of object ids in all tuples (ntupledata x 1)
mjtNum* tuple_objprm; // array of object params in all tuples (ntupledata x 1)
// keyframes
mjtNum* key_time; // key time (nkey x 1)
mjtNum* key_qpos; // key position (nkey x nq)
mjtNum* key_qvel; // key velocity (nkey x nv)
mjtNum* key_act; // key activation (nkey x na)
mjtNum* key_mpos; // key mocap position (nkey x nmocap*3)
mjtNum* key_mquat; // key mocap quaternion (nkey x nmocap*4)
mjtNum* key_ctrl; // key control (nkey x nu)
// names
int* name_bodyadr; // body name pointers (nbody x 1)
int* name_jntadr; // joint name pointers (njnt x 1)
int* name_geomadr; // geom name pointers (ngeom x 1)
int* name_siteadr; // site name pointers (nsite x 1)
int* name_camadr; // camera name pointers (ncam x 1)
int* name_lightadr; // light name pointers (nlight x 1)
int* name_flexadr; // flex name pointers (nflex x 1)
int* name_meshadr; // mesh name pointers (nmesh x 1)
int* name_skinadr; // skin name pointers (nskin x 1)
int* name_hfieldadr; // hfield name pointers (nhfield x 1)
int* name_texadr; // texture name pointers (ntex x 1)
int* name_matadr; // material name pointers (nmat x 1)
int* name_pairadr; // geom pair name pointers (npair x 1)
int* name_excludeadr; // exclude name pointers (nexclude x 1)
int* name_eqadr; // equality constraint name pointers (neq x 1)
int* name_tendonadr; // tendon name pointers (ntendon x 1)
int* name_actuatoradr; // actuator name pointers (nu x 1)
int* name_sensoradr; // sensor name pointers (nsensor x 1)
int* name_numericadr; // numeric name pointers (nnumeric x 1)
int* name_textadr; // text name pointers (ntext x 1)
int* name_tupleadr; // tuple name pointers (ntuple x 1)
int* name_keyadr; // keyframe name pointers (nkey x 1)
int* name_pluginadr; // plugin instance name pointers (nplugin x 1)
char* names; // names of all objects, 0-terminated (nnames x 1)
int* names_map; // internal hash map of names (nnames_map x 1)
// paths
char* paths; // paths to assets, 0-terminated (npaths x 1)
};
typedef struct mjModel_ mjModel;
#endif // MUJOCO_MJMODEL_H_