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    b2BodyDef bodyLadder1Def;
    bodyLadder1Def.type = b2_dynamicBody;
    bodyLadder1Def.position.Set(400 / PTM_RATIO, 400 / PTM_RATIO); // PTM_RATIO = 46
    bodyLadder1Def.angularDamping  = 0.5f;
    bodyLadder1Def.linearDamping   = 0.5f;

    b2Vec2 verticesLadder1[4];
    verticesLadder1[0].Set(0.0000f, 0.0000f);
    verticesLadder1[1].Set(2.6739f, 0.0000f);
    verticesLadder1[2].Set(2.6739f, 0.4130f);
    verticesLadder1[3].Set(0.0000f, 0.4130f);

    b2PolygonShape dynamicBox;
    dynamicBox.Set(verticesLadder1, 4);

    b2Body *ladder1Body = world->CreateBody(&bodyLadder1Def);

    b2FixtureDef fixtureLadder1Def;
    fixtureLadder1Def.shape           = &dynamicBox;
    fixtureLadder1Def.density         = 100.0f;
    fixtureLadder1Def.friction        = 1.0f;
    fixtureLadder1Def.restitution     = 0.5f;
    fixtureLadder1Def.filter.maskBits = 0x0001;

    ladder1Body->CreateFixture(&fixtureLadder1Def);

    // part 2

    b2BodyDef bodyLadder2Def;
    bodyLadder2Def.type = b2_dynamicBody;
    bodyLadder2Def.position.Set(400 / PTM_RATIO, 400 / PTM_RATIO);
    bodyLadder2Def.angularDamping  = 0.5f;
    bodyLadder2Def.linearDamping   = 0.5f;

    b2Vec2 verticesLadder2[4];

    verticesLadder2[0].Set(0.0000f, 0.0000f);
    verticesLadder2[1].Set(3.9560f, 0.0000f);
    verticesLadder2[2].Set(3.9560f, 0.2391f);
    verticesLadder2[3].Set(0.0000f, 0.2391f);

    b2PolygonShape dynamicLadder2Box;
    dynamicLadder2Box.Set(verticesLadder2, 4);

    b2Body *ladder2Body = world->CreateBody(&bodyLadder2Def);

    b2FixtureDef fixtureLadder2Def;
    fixtureLadder2Def.shape           = &dynamicLadder2Box;
    fixtureLadder2Def.density         = 100.0f;
    fixtureLadder2Def.friction        = 1.0f;
    fixtureLadder2Def.restitution     = 0.5f;
    fixtureLadder2Def.filter.maskBits = 0x0001;

    ladder2Body->CreateFixture(&fixtureLadder2Def);

    // joint
    b2PrismaticJointDef prismaticJointDef;
    b2Vec2 worldAxis(1.0f, 0.0f);
    prismaticJointDef.Initialize(ladder1Body, ladder2Body, b2Vec2((400.0f) / PTM_RATIO, (400.0f) / PTM_RATIO), worldAxis);
   
    world->CreateJoint(&prismaticJointDef);

   
    // cylinder and rootCylinder joint
    b2RevoluteJointDef cylinderJointDef;
    cylinderJointDef.Initialize(cylinderBody, rootCylinder, cylinderBody->GetPosition());
   
    // cylinder and rootCylinder joint   
    b2PrismaticJointDef hydroCylinderJointDef;   
    b2Vec2 axis = cylinderBody->GetPosition() - pistonBody->GetPosition();                       
   
    hydroCylinderJointDef.Initialize(cylinderBody, pistonBody, cylinderBody->GetPosition(), axis);
    hydroCylinderJointDef.lowerTranslation    = -20.0f;
    hydroCylinderJointDef.upperTranslation   = 0.0f;
    hydroCylinderJointDef.enableLimit            = true;
    hydroCylinderJointDef.maxMotorForce      = 10.0f;
    hydroCylinderJointDef.motorSpeed           = 0.0f;
    hydroCylinderJointDef.enableMotor           = true;

    // create joints                                 
    world->CreateJoint(&cylinderJointDef);
    world->CreateJoint(&hydroCylinderJointDef); 
 

hydroCylinderJointDef.enableLimit = false;