Adding a force to an object

The Rigidbody component allows you to apply physics-based forces to objects and make them respond to gravity, collisions, and other physical properties. In this tutorial, you will learn how to:

• Add a constant force to an object.
• Add an explosion force to an object.

Add a constant force to an object

To add a constant force to an object with rigidbody:

1. Add an object to the scene and make sure the object has a non-mesh collider attached to it.

   • In this tutorial, we use model Spikes_Normal to the scene by selecting it via Scenery>Models>Basics.

   • The model added comes with a mesh collider, so we turn off the mesh collider and add a sphere collider.

   

2. Add a rigidbody to the object by choosing + Component>Gameplay>Rigidbody, making it an YaEntity.

3. Add the following script to the entity to apply a constant force to it. For more information on how to add a script, see Creating or adding scripts.

   local selfEntity = script:SelfEntity()
   
   -- Set a force of 3000 Newtons in a specific direction
   local force = 3000
   local forwardForce = float3.Mul(float3.New(0, 0, 1), force)
   
    -- Set a 0.05-second delay before starting and 0.1 seconds to wait between events 
   YaTimeAPI.ScheduleAtInterval(0.05, 0.1, function()
       -- Apply the force to the entity
       PhysicsAPI.AddForce(selfEntity, forwardForce)
   end)
   

   In this example, we are applying a 3000-Newton force to the object in the forward direction of this object's Z-axis.

4. Save the script and enter Play Mode to playtest.

   

Add an explosion force to an object

Explosion force is a sphere that can be applied to an object to simulate explosion effects. You can call the AddExplosionImpulseForce function to add explosion force to an object.

1. Add an object to the scene and make sure the object has a non-mesh collider attached to it.

   • In this tutorial, we use model Transverse_Roadblocks to the scene by selecting it via Scenery>Models>Basics.

   • The model comes with a mesh collider, so we turn off the mesh collider and add a sphere collider.

   

2. Add a rigidbody to the object by choosing + Component>Gameplay>Rigidbody, making it a YaEntity.

3. Add the following script to the entity to apply a force to it. For more information on how to add a script, see Creating or adding scripts.

   local selfEntity = script:SelfEntity()
   
   local cmp = script:GetYaComponent("YaMovableComponent")
   local explosionPosition = cmp:GetPosition()
   
   YaTimeAPI.WaitFor(5, function()
       PhysicsAPI.AddExplosionImpulseForce(selfEntity, 1000, explosionPosition, 15, 1000)
   end)
   

   In this example, we are using the function PhysicsAPI.AddExplosionImpulseForce to apply an explosion force to the rigid body. After a 5-second delay, an explosion force of 1000 Newtons is applied at the specified position, with a radius of 15, and moved along the y-axis as if to lift the object upwards.

4. Save the script and enter Play Mode to playtest.