How to make NPC attack the player

Troubleshooting ai
1

Im trying to develop FPS game where monsters come at me and attack me.

How i create the player(which is 1st person, so a camera)

playerNode = new Node(“Player”);

    CapsuleCollisionShape capsuleShape = new CapsuleCollisionShape(1.5f, 6f, 1);
    player = new CharacterControl(capsuleShape, 0.05f);
    player.setJumpSpeed(20);
    player.setFallSpeed(40);
    player.setGravity(40);
    playerNode.addControl(player);


    player.setPhysicsLocation(new Vector3f(-150, -10, -20));


    bulletAppState.getPhysicsSpace().add(player);
    rootNode.attachChild(playerNode);

How i create a NPC

Node monster = (Node) assetManager.loadModel(“Models/Oto/Oto.mesh.xml”);
monster.setLocalScale(0.7f);
monster.setLocalTranslation(-120, -20, 0);
monster.setUserData(“Id”, id);
monster.setUserData(“Hp”, 100);
monster.setName(“Monster” + id);
rootNode.attachChild(monster);
control = monster.getControl(AnimControl.class);
control.addListener(this);
channel = control.createChannel();
channel.setAnim(“Walk”);
channel.setLoopMode(LoopMode.Loop);

monster_phys = new CharacterControl(capsuleShape, 0.01f);
// Attach physical properties to model and PhysicsSpace
monster_phys.setJumpSpeed(20f);
monster_phys.setMaxSlope(1.5f);
monster_phys.setPhysicsLocation(new Vector3f(10, 5, 0));
monster.addControl(myCharacter_phys);
bulletAppState.getPhysicsSpace().add(monster_phys);

I know that their cant be any collison but i just want the monsters to walk around normal.
Now here is my question, how am i supposed to make this NPC come to attack me?

I’ve tried all the possible things with monster_phys.setWalkDirection and nothing worked.
I just want the NPC to come to my location.

Can anyone please help me, i’ve searched the whole forum and didnt find the right solution.

2

Maybe try something like Garrys Mod or another FPS mod, its much easier making models you just loaded “attack” something else there.

3

Yeah, i was thinking about using some other mod, but i would really like to continue by just using jMonkey.
So you wouldn’t know how to implement that?

I never seem to guess how to setWalkDirection of a NPC to come in my direction.

4

No, I don’t know how to implement that, I guess it has something to do with vector math or the stuff that MonkeyZone does, who ever wrote that…

5

Get the Vector location of the player and the Vector location of the NPC, substract them and do setWalkDirection with that value. Here is an example:

[java]
public void update(float tpf)
{
Vector3f playerLocation = player.getWorldTranslation();
Vector3f npcLocation = npc.getWorldTranslation();
Vector3f offset = player.subtract(npcLocation); // offset from npc to player
npc.setWalkDirection(offset).normalize();

}
[/java]

This should get the npc to walk towards you.

Then if you want the NPC to attack you, check the distance and if less than X do an attack animation.

6

[java]
public void update(float tpf)
{
Vector3f playerLocation = player.getWorldTranslation();
Vector3f npcLocation = npc.getWorldTranslation();
Vector3f offset = player.subtract(npcLocation); // offset from npc to player
npc.setWalkDirection(offset).normalize();

}
[/java]
.

Thanks that worked, you just saved 10 hours of my life :smiley:

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