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Mujoco C++ example: List all bodies

This simple example shows how to load a MuJoCo model from an XML file and list all bodies in the model along with their IDs.

#include <mujoco/mujoco.h>
#include <cstdio>

int main(int argc, char** argv) {
    // Check args
    if (argc < 2) {
        printf("Usage: %s model.xml\n", argv[0]);
        return 1;
    }

    // Load model
    char error[1000] = "Could not load binary model";
    mjModel* m = mj_loadXML(argv[1], nullptr, error, 1000);
    if (!m) {
        printf("%s\n", error);
        return 1;
    }

    // Create data
    mjData* d = mj_makeData(m);

    // Loop over all bodies
    printf("Bodies in the model:\n");
    for (int i = 0; i < m->nbody; i++) {
        const char* name = mj_id2name(m, mjOBJ_BODY, i);
        if (name)
            printf("  id %d: %s\n", i, name);
        else
            printf("  id %d: (unnamed)\n", i);
    }

    // Free MuJoCo structures
    mj_deleteData(d);
    mj_deleteModel(m);

    return 0;
}

How to compile

g++ -o list_bodies list_bodies.cpp -lmujoco -I/opt/mujoco/include -L/opt/mujoco/lib -Wl,-rpath,/opt/mujoco/lib

Usage example

./list_bodies ~/mujoco_menagerie/franka_fr3/fr3.xml        
Bodies in the model:
  id 0: world
  id 1: base
  id 2: fr3_link0
  id 3: fr3_link1
  id 4: fr3_link2
  id 5: fr3_link3
  id 6: fr3_link4
  id 7: fr3_link5
  id 8: fr3_link6
  id 9: fr3_link7