Rigidbody Won't Respond to applyImpulse

Help & Support
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1

Hello community!
I’m having some trouble getting a rigidbody to move on a keypress. Originally I was using translateLocal, but once I decided to change the jumping mechanics to raycasting, I had to change the entity to a dynamic rigidbody. Right now, the code looks essentially like this:

CharacterControl.prototype.move = function(dx, dy, dz) {
this.entity.rigidbody.applyImpulse(dx, dy, dz);
};

And then the keypress looks like this:

CharacterControl.prototype.update = function(dt) {
let keyboard = this.app.keyboard;
this.speed = 7;
if( keyboard.isPressed(pc.KEY_W) ) {
this.move(0, 0, this.speed * dt)
};
};

I’m new to Javascript (only been using it for a couple of weeks) so forgive me if it looks messy and unoptimized.

2

Hi @cyron_007 and welcome!

If you’re currently using the same value as you did for translateLocal(), the force is probably too low.

Also, if this is for forward movement, I suggest using applyForce(). For jumping, applyImpulse() will be the best option.

3

Hi, thank you for the advice!
I changed this.speed to 30000 and there was still no movement. I tried doing

this.entity.rigidbody.teleport(this.entity.getPosition().x+dx, this.entity.getPosition().y+dy, this.entity.getPosition().z+dz);

which worked, but I still can’t jump. Using applyImpulse() for the jump still doesn’t work. Thanks though!

4

I would try to check if your move function received the correct information. You can add something like below and use the console of your browser to read the information.

console.log(dz);

Also check the rigidbody sittings of the entity. For example if Linear Damping is set to 1, the rigidbody won’t move.

1 Like
5

It looks like it’s recieving the correct information, and both linear and angular dampening were set to zero. I tried doing this, and it returned “move() failed”:

MoveBox.prototype.move = function(dx, dy, dz) {
   console.log(dz);
   let result = this.entity.rigidbody.applyForce(dx, dy, dz);
    if(result) {
        console.log("move() successful");
        return result;
    }
    else {
        console.log("move() failed");
    };

};

Also, this is my code for the jumping system:

(in initialize function) {
   this.isGrounded = true;
   this.velocityY = 0;
}; 
(in update function) {
if(keyboard.wasPressed(pc.KEY_SPACE) && this.isGrounded) {
        this.velocityY = this.jumpForce;
        this.isGrounded = false;
    }
this.velocityY += this.gravity * dt;
this.entity.rigidbody.applyImpulse(0, this.velocityY * dt, 0);
};

this.jumpForce is set to 1000. The program is registering the keypresses, sending information to correct recipients, but something about the applyForce() and applyImpulse() functions aren’t working correctly, because when I change them to translateLocal() or rigidbody.teleport(), it works fine.

6

Make also sure the Linear Factor of the rigidbody is not set to 0.

If you share the editor link of your project, I can take a look when I have some time.

1 Like
7

Of course! I have both the Linear and Angular factors of the rigidbody set to 1. Here is the link to my project: PlayCanvas | HTML5 Game Engine

8

The collision component is missing. This is the volume for the rigidbody.

9

Ah, thank you. Am I supposed to be changing the friction / restitution to make it stop bouncing around so much?

10

Yes, it can be challenging to find the right balance between all values.