How to use collideTerrain?

[Trenki]

I wanted to check if entities collided with terrain, so I used collideTerrain like CollideEntities, but it didn't work.

this.entityID = ents.add(
    opts.playerStart, // starting location
    opts.playerWidth, opts.playerHeight,
    null, null, // no mesh for now, no meshOffset, 
    true, true
  )
  // make player entity it collide with terrain and other entities
ents.addComponent(this.entityID, ents.names.collideTerrain,{
  onCollide: (other) => {
    console.log('Entity', this.entityID, 'Terrain onCollide', other)
  },
  callback: (other) => {
    console.log('Entity', this.entityID, 'Terrain callback', other)
  }
})

[fenomas]

Hi, the only caveat on collideTerrain is that it assumes the entity already has the physics component (it's the physics engine that actually emits the collision event). Probably noa should emit a log warning if that's not the case I guess.

However for the code you posted, the entity is getting the physics component and the code works as expected for me. To be clear collideTerrain calls a callback property, and it passes the impulse of the collision and the id of the entity. So the expected usage is like:

ents.addComponent(entityID, ents.names.collideTerrain,{
  callback: (impulse, id) => {
    console.log('Entity', id, 'terrain collision, impulse:', impulse)
  }
})

Anyway for me your code runs as expected, and the callback function gets called normally (as soon as the spawned entity falls to the ground). What are you seeing?

[Trenki]

Sorry, I misunderstood the meaning of the function, which made me think the desired effect was not achieved.The effect I want to know is that Entity hits the terrain while walking forward, how should this state be obtained?

[fenomas]

Hi, the callback should get fired when the entity hits terrain while walking, or it does for me. Note that if the entity walks into a one-block barrier, and has the "autoStep" property, then it will step onto the barrier instead of colliding. What behavior are you seeing?

[Trenki]

Hi,Andy.I see, my question is how to make the Entity walk without using receivesInputs.

[MCArth]

Use noa.ents.setPosition(EId, [1, 2, 3]) for direct position setting.

Alternatively you can modify the state of their movement component (assuming they have one) - source is /src/components/movement.js

noa.ents.getMovement(EId)

Check out the API documentation in /doc/API.md - it's very helpful.