Comprehensive Guide to Babylon.js Game Engine, undefined

Forces and Impulses

Apply physics forces to objects in your scene:

// Apply a continuous force (newtons)
sphere.physicsImpostor.applyForce(
    new BABYLON.Vector3(0, 0, 10), // Force direction and magnitude
    sphere.getAbsolutePosition() // Application point
);

// Apply an impulse (instantaneous force)
box.physicsImpostor.applyImpulse(
    new BABYLON.Vector3(5, 0, 0), // Impulse direction and magnitude
    box.getAbsolutePosition() // Application point
);

// Set linear velocity directly
sphere.physicsImpostor.setLinearVelocity(new BABYLON.Vector3(0, 5, 0));

// Set angular velocity (rotation)
box.physicsImpostor.setAngularVelocity(new BABYLON.Vector3(0, 2, 0));

// Apply a torque (rotational force)
box.physicsImpostor.applyTorque(new BABYLON.Vector3(0, 10, 0));

Interactive Forces

Create user-controlled physics interactions:

// Add force on key press
scene.onKeyboardObservable.add((kbInfo) => {
    if (kbInfo.type === BABYLON.KeyboardEventTypes.KEYDOWN) {
        switch (kbInfo.event.key) {
            case "ArrowUp":
                sphere.physicsImpostor.applyImpulse(
                    new BABYLON.Vector3(0, 0, -10),
                    sphere.getAbsolutePosition()
                );
                break;
            case "ArrowDown":
                sphere.physicsImpostor.applyImpulse(
                    new BABYLON.Vector3(0, 0, 10),
                    sphere.getAbsolutePosition()
                );
                break;
            case "ArrowLeft":
                sphere.physicsImpostor.applyImpulse(
                    new BABYLON.Vector3(-10, 0, 0),
                    sphere.getAbsolutePosition()
                );
                break;
            case "ArrowRight":
                sphere.physicsImpostor.applyImpulse(
                    new BABYLON.Vector3(10, 0, 0),
                    sphere.getAbsolutePosition()
                );
                break;
            case " ": // Space key
                sphere.physicsImpostor.applyImpulse(
                    new BABYLON.Vector3(0, 10, 0), // Jump
                    sphere.getAbsolutePosition()
                );
                break;
        }
    }
});