Class: RGame::Engine::Components::CircleCollider

Inherits:
RGame::Engine::Component show all
Defined in:
lib/rgame/engine/components/circle_collider.rb

Overview

A circular collision shape on a node. It registers itself with the scene's CollisionWorld system when it enters the tree and unregisters on leaving — the engine fires both hooks, so a spawned/despawned entity can't leak a registration. Its world centre is the node's resolved absolute origin; the layer is an opaque tag the game reads in its on_hit handler to decide what a contact means (bullet-vs-rock, etc.). See docs/api/systems.md.

Instance Attribute Summary collapse

Attributes inherited from RGame::Engine::Component

#node

Instance Method Summary collapse

Methods inherited from RGame::Engine::Component

#context, #control, #draw, #sweep_freed, #update

Methods included from Signal::DSL

#signal

Constructor Details

#initialize(radius:, layer: :default) ⇒ CircleCollider

Returns a new instance of CircleCollider.



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# File 'lib/rgame/engine/components/circle_collider.rb', line 22

def initialize(radius:, layer: :default)
  super()
  @radius = radius
  @layer = layer
end

Instance Attribute Details

#layer ⇒ Object (readonly)

Returns the value of attribute layer.



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# File 'lib/rgame/engine/components/circle_collider.rb', line 20

def layer
  @layer
end

#radius ⇒ Object

radius is writable so a pooled entity (e.g. a multi-tier rock) can retune its shape on reset; CollisionWorld reads it fresh each frame, so no re-registration.



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# File 'lib/rgame/engine/components/circle_collider.rb', line 19

def radius
  @radius
end

Instance Method Details

#cx ⇒ Object

World-space centre — the node's resolved absolute origin.



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# File 'lib/rgame/engine/components/circle_collider.rb', line 32

def cx = node.abs_x

#cy ⇒ Object 



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# File 'lib/rgame/engine/components/circle_collider.rb', line 33

def cy = node.abs_y

#emit_hit(other) ⇒ Object

Called by CollisionWorld on contact (the signal's emit is otherwise private).



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# File 'lib/rgame/engine/components/circle_collider.rb', line 40

def emit_hit(other) = on_hit_signal.emit(other)

#on_attach ⇒ Object 



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# File 'lib/rgame/engine/components/circle_collider.rb', line 28

def on_attach = node.system(CollisionWorld).register(self)

#on_detach ⇒ Object 



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# File 'lib/rgame/engine/components/circle_collider.rb', line 29

def on_detach = node.system(CollisionWorld)&.unregister(self)

#overlap?(other) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rgame/engine/components/circle_collider.rb', line 35

def overlap?(other)
  Engine::CircleCollider.overlap?(cx, cy, @radius, other.cx, other.cy, other.radius)
end