Where I can find example of second application of raycast?

Help & Support
1

I see there are 2 applications of raycast: entity picking and determine if an entity is on the ground:

Ray casting has other applications too. An entity can probe the environment by firing ray casts. For example, to determine if an entity is on the ground, it can fire a ray cast directly downwards some distance and check if it intersects with the environment.

With entity picking I see there is example.

So Where I can find example of second application of raycast it is determine if an entity is on the ground?

2

Not sure if there is an example, but it isn’t much different. You just need to cast a ray from a position pointing to the ground.

Something like this:

    // this will cast a ray 100 units from the current entity pos pointing down
    var from = this.entity.getPosition();
    var to = new pc.Vec3().copy(from);
    to.y -= 100;

    var result = this.app.systems.rigidbody.raycastFirst(from, to);
    if(result){}
3

Yes I have the ray
const ray = new pc.Ray(this.carEntity.getPosition());

4

A ray requires a position and a direction:

https://developer.playcanvas.com/en/api/pc.Ray.html

So if you are using a ray in your code, point it to the ground like this:

const ray = new pc.Ray(this.carEntity.getPosition(), pc.Vec3.DOWN);
1 Like
5

ok I get it
because I read the ray is infinite but it can be set with some distance