45 lines
1.4 KiB
GDScript3
45 lines
1.4 KiB
GDScript3
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extends Node2D
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@export var max_droplets: int = 100
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@export var spawn_rate: float = 0.1
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var spawn_timer: float = 0.1
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func _physics_process(delta):
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var mm_node = $MultiMeshInstance2D
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var mm = mm_node.multimesh
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# 1. Get all current RigidBody2D children
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var fluid_bodies = get_children().filter(func(node): return node is RigidBody2D)
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# 2. FORCE MultiMesh to match the current body count
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# This is why they weren't 'registering'—the MultiMesh slot didn't exist yet!
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if mm.instance_count != fluid_bodies.size():
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mm.instance_count = fluid_bodies.size()
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# 3. Visual Sync
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for i in range(fluid_bodies.size()):
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var body = fluid_bodies[i]
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# Subtract the container's position so particles don't "drift"
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var t = Transform2D(0.0, body.global_position - global_position)
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mm.set_instance_transform_2d(i, t)
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# 4. Interaction (Surface Tension)
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for i in range(fluid_bodies.size()):
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for j in range(i + 1, fluid_bodies.size()):
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var b1 = fluid_bodies[i]
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var b2 = fluid_bodies[j]
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var dist_vec = b1.global_position - b2.global_position
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var dist = dist_vec.length()
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if dist < 40.0:
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var force = dist_vec.normalized() * 5.0
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b1.apply_central_force(-force)
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b2.apply_central_force(force)
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# 5. Spawning
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spawn_timer += delta
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if spawn_timer >= spawn_rate and fluid_bodies.size() < max_droplets:
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%SceneManager.addDropplet()
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mm.instance_count = fluid_bodies.size()
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spawn_timer = 0.0
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