java - How can I create Kinematic Objects in jBullet? -

i trying make game engine , want camera controlled player , effected other jbullet entities in java. got suggested use kinematic objects looked them. couldn't find documentation understand.

can explain how set , use kinematic objects or @ least show me can start?

the documentation kinematiccharactercontroller, found here isn't entirely helpful, source in characterdemo can be. 2 main properties defined in demo.

    public kinematiccharactercontroller character;     public paircachingghostobject ghostobject; 

the ghost can used dynamic collision detection, not automatically react events. character can moved changing transform.

    //from source src\com\bulletphysics\demos\character\characterdemo.java     transform starttransform = new transform();     starttransform.setidentity();     starttransform.origin.set(0.0f, 4.0f, 0.0f);      vector3f worldmin = new vector3f(-1000f,-1000f,-1000f);     vector3f worldmax = new vector3f(1000f,1000f,1000f);     axissweep3 sweepbp = new axissweep3(worldmin, worldmax);      ghostobject = new paircachingghostobject();     ghostobject.setworldtransform(starttransform);     sweepbp.getoverlappingpaircache().setinternalghostpaircallback(new ghostpaircallback());     float characterheight = 1.75f * characterscale;     float characterwidth = 1.75f * characterscale;     convexshape capsule = new capsuleshape(characterwidth, characterheight);     ghostobject.setcollisionshape(capsule);     ghostobject.setcollisionflags(collisionflags.character_object);      float stepheight = 0.35f * characterscale;     character = new kinematiccharactercontroller(ghostobject, capsule, stepheight);       dynamicsworld.addcollisionobject(ghostobject, collisionfiltergroups.character_filter, (short)(collisionfiltergroups.static_filter | collisionfiltergroups.default_filter));      dynamicsworld.addaction(character); 

it wise extend motionstate class hold transform

   public class mymotionstate extends motionstate {         private transform worldtransform;         public mymotionstate()          {             worldtransform = new transform();             worldtransform.setidentity();         }          @override         public transform getworldtransform(transform worldtrans)          {             worldtrans.set(worldtransform);             return worldtrans;         }          @override         public void setworldtransform(transform worldtrans)          {             worldtransform.set(worldtrans);         }  } 

and linking kinematic rigidbody applying physics character, , getting info on rendering.

    rigidbody.setcollisionflags(rigidbody.getcollisionflags() | collisionflags.kinematic_object);       rigidbody.setactivationstate(collisionobject.disable_deactivation); 

don't forget update physics engine once every iteration of game loop.

    transform transform = new transform();     transform.setidentity();     transform.origin.set(input.getx(), input.gety(), input.getz());     mymotionstate.setworldtransform(transform);     rigidbody.setcenterofmasstransform(mymotionstate.getworldtransform()); 

if prefer, put these in maincharacter class or whatever call (i object oriented feel , ease understand)

    public class maincharacter implements keylistener, mouselistener     {         private dynamicsworld world;         private mymotionstate mymotionstate;         private rigidbody rigidbody;         private kinematiccharactercontroller character;         private convexshape shape;         private texture texture;         private ghostobject ghost;         private vector3f pos;         public maincharacter(dynamicsworld world, vector3f initialposition, convexshape shape, texture texture)         {             this.world = world;             rigidbodyconstructioninfo constructinfo = new rigidbodyconstructioninfo(...);             this.mymotionstate = mymotionstate;             rigidbody = new rigidbody(constructinfo);             ghost = new ghostobject();             character = new kinematiccharactercontroller(ghost,shape,1);         }         public void render()         {             glbegin(gl_quads);                 glvertex3f(...                 ...             glend();         }         public void mousemoved(mouseevent e)         {                 //pseudocode                 this.yaw = e.getdx();                 this.pitch = e.getdy();         }         public void keypressed(keyevent e)         {             vector3f dpos = null;             if(e.getkeychar() == 'w')             {                 dpos.x = 10;             }             else if(e.getkeychar() == 's')             {                 dpos.x = -10;             }             etc...              move(dpos.x,dpos.y,dpos.z);         }         public void move(float dx, float dy, float dz) {             pos.z += dx * (float) math.cos(math.toradians(yaw - 90)) + dz *        math.cos(math.toradians(yaw));             pos.x -= dx * (float) math.sin(math.toradians(yaw - 90)) + dz * math.sin(math.toradians(yaw));             pos.y += dy * (float) math.sin(math.toradians(pitch - 90)) + dz * math.sin(math.toradians(pitch));             //pseudocode             rigidbody.update(pos);             world.update(pos);         }    } 

i hope have helped you.