# GrassMultiMesh.gd
extends MultiMeshInstance3D
var mm: MultiMesh
var parent_node: GrassController
var rng: RandomClass = RandomClass.new()

func _ready() -> void:
	parent_node = get_parent() as GrassController
	if parent_node == null:
		Log.pr("Error: Parent node is not a GrassController!")

func setup_multimesh() -> void:
	if parent_node == null:
		Log.pr("Error: Parent node not available in setup_multimesh")
		return
	
	# Use the same RNG seed as the parent for consistency
	if parent_node.parent_node and parent_node.parent_node.cell_info:
		rng.set_seed(parent_node.parent_node.cell_info.cell_seed)
	
	# Load the mesh resource directly
	var mesh = load("res://Stages/Test3D/assets/stylizedGrassMeshes/grass2_mesh.res")
	if mesh == null:
		Log.pr("Error: Could not load grass mesh")
		return
	
	# Create new MultiMesh instance
	mm = MultiMesh.new()
	
	# Configure the MultiMesh
	mm.transform_format = MultiMesh.TRANSFORM_3D
	mm.instance_count = parent_node.grass_instance_range
	mm.mesh = mesh
	
	# Generate random positions for grass using seeded RNG
	for i in range(mm.instance_count):
		var random_pos = Vector3(
			rng.randf_range(-1.0, 1.0),
			0.0,
			rng.randf_range(-1.0, 1.0)
		)
		
		var random_rotation = rng.randf_range(0.0, TAU)
		var basis = Basis(Vector3.UP, random_rotation)
		
		var random_scale = rng.randf_range(0.05, 0.3)
		basis = basis.scaled(Vector3(random_scale, random_scale, random_scale))
		
		var tx = Transform3D(basis, random_pos)
		mm.set_instance_transform(i, tx)
	
	# Assign the MultiMesh to this node
	multimesh = mm
	cast_shadow = GeometryInstance3D.SHADOW_CASTING_SETTING_OFF