godot-2d-physics

name

godot-2d-physics

description

Expert patterns for Godot 2D physics including collision layers/masks, Area2D triggers, raycasting, and PhysicsDirectSpaceState2D queries. Use when implementing collision detection, trigger zones, line-of-sight systems, or manual physics queries. Trigger keywords: CollisionShape2D, CollisionPolygon2D, collision_layer, collision_mask, set_collision_layer_value, set_collision_mask_value, Area2D, body_entered, body_exited, RayCast2D, force_raycast_update, PhysicsPointQueryParameters2D, PhysicsShapeQueryParameters2D, direct_space_state, move_and_collide, move_and_slide.

2D Physics

Expert guidance for collision detection, triggers, and raycasting in Godot 2D.

NEVER Do

• NEVER scale CollisionShape2D nodes — Use the shape handles in the editor, NOT the Node2D scale property. Scaling causes unpredictable physics behavior and incorrect collision normals [12].
• NEVER confuse collision_layer with collision_mask — Layer = "What AM I?", Mask = "What do I DETECT?". Setting both to the same value is usually wrong [13].
• NEVER multiply velocity by delta when using move_and_slide() — move_and_slide() automatically includes timestep. Only multiply gravity/acceleration by delta [14].
• NEVER forget force_raycast_update() for manual mid-frame raycasts — Raycasts update once per physics frame. If you change target_position, you MUST force an update [15].
• NEVER use get_overlapping_bodies() every frame — It is expensive. Cache results with body_entered/body_exited signals instead [16].
• NEVER modify RigidBody2D state directly in _process — Use _integrate_forces() for safe, synchronized access to [17, 411].