3 body problem with dot trail

.editorconfig

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+root = true
+
+[*]
+charset = utf-8

.gitattributes

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+# Normalize EOL for all files that Git considers text files.
+* text=auto eol=lf

.gitignore

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+# Godot 4+ specific ignores
+.godot/
+/android/

Blob.gd

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+extends RigidBody3D
+
+class_name Blob3D
+
+const DOT_SPACING: float = 1.0
+
+var cumulative_delay: float
+var dot_color: Color
+
+func _init(
+	material: StandardMaterial3D,
+	initial_position: Vector3,
+	initial_velocity: Vector3,
+	radius: float = 0.5,
+	mass: float = 1,
+) -> void:
+	self.position = initial_position
+	self.linear_velocity = initial_velocity
+	self.mass = mass
+
+	var mesh = MeshInstance3D.new()
+	mesh.mesh = SphereMesh.new()
+	mesh.mesh.radius = radius
+	mesh.mesh.height = 2*radius
+	mesh.material_override = material
+
+	var collision = CollisionShape3D.new()
+	collision.shape = SphereShape3D.new()
+	collision.shape.radius = radius
+
+	self.add_child(mesh)
+	self.add_child(collision)
+
+	self.dot_color = random_color()
+
+func _process(delta: float) -> void:
+	self.cumulative_delay += delta
+
+	if self.cumulative_delay >= DOT_SPACING:
+		self.add_sibling(OrbitDot3D.new(self.position, self.dot_color))
+		self.cumulative_delay = 0
+
+func random_color() -> Color:
+	return Color.from_hsv(randf(), 0.8, 0.8)

Blob.gd.uid

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+uid://sbifwu5mnc67

camera_3d.gd

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+extends Camera3D
+
+
+# Called when the node enters the scene tree for the first time.
+func _ready() -> void:
+	print("Created camera.")
+
+# Called every frame. 'delta' is the elapsed time since the previous frame.
+func _process(delta: float) -> void:
+	pass

camera_3d.gd.uid

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+uid://4wscni70so3k

dot.gd

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+extends MeshInstance3D
+
+class_name OrbitDot3D
+
+var expiration: float = 120.0
+var delay: float
+
+func _init(position: Vector3, color: Color) -> void:
+	self.position = position
+
+	self.mesh = SphereMesh.new()
+	self.mesh.radius = 0.1
+	self.mesh.height = 2*self.mesh.radius
+	self.material_override = StandardMaterial3D.new()
+	self.material_override.albedo_color = color
+
+	self.delay = 0
+
+func _process(delta: float) -> void:
+	self.delay += delta
+
+	if delay >= self.expiration:
+		self.queue_free()

dot.gd.uid

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+uid://bolr2a1petpon

icon.svg

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+<svg xmlns="http://www.w3.org/2000/svg" width="128" height="128"><rect width="124" height="124" x="2" y="2" fill="#363d52" stroke="#212532" stroke-width="4" rx="14"/><g fill="#fff" transform="translate(12.322 12.322)scale(.101)"><path d="M105 673v33q407 354 814 0v-33z"/><path fill="#478cbf" d="m105 673 152 14q12 1 15 14l4 67 132 10 8-61q2-11 15-15h162q13 4 15 15l8 61 132-10 4-67q3-13 15-14l152-14V427q30-39 56-81-35-59-83-108-43 20-82 47-40-37-88-64 7-51 8-102-59-28-123-42-26 43-46 89-49-7-98 0-20-46-46-89-64 14-123 42 1 51 8 102-48 27-88 64-39-27-82-47-48 49-83 108 26 42 56 81zm0 33v39c0 276 813 276 814 0v-39l-134 12-5 69q-2 10-14 13l-162 11q-12 0-16-11l-10-65H446l-10 65q-4 11-16 11l-162-11q-12-3-14-13l-5-69z"/><path d="M483 600c0 34 58 34 58 0v-86c0-34-58-34-58 0z"/><circle cx="725" cy="526" r="90"/><circle cx="299" cy="526" r="90"/></g><g fill="#414042" transform="translate(12.322 12.322)scale(.101)"><circle cx="307" cy="532" r="60"/><circle cx="717" cy="532" r="60"/></g></svg>

icon.svg.import

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+[remap]
+
+importer="texture"
+type="CompressedTexture2D"
+uid="uid://b25a736wmlgp1"
+path="res://.godot/imported/icon.svg-218a8f2b3041327d8a5756f3a245f83b.ctex"
+metadata={
+"vram_texture": false
+}
+
+[deps]
+
+source_file="res://icon.svg"
+dest_files=["res://.godot/imported/icon.svg-218a8f2b3041327d8a5756f3a245f83b.ctex"]
+
+[params]
+
+compress/mode=0
+compress/high_quality=false
+compress/lossy_quality=0.7
+compress/uastc_level=0
+compress/rdo_quality_loss=0.0
+compress/hdr_compression=1
+compress/normal_map=0
+compress/channel_pack=0
+mipmaps/generate=false
+mipmaps/limit=-1
+roughness/mode=0
+roughness/src_normal=""
+process/channel_remap/red=0
+process/channel_remap/green=1
+process/channel_remap/blue=2
+process/channel_remap/alpha=3
+process/fix_alpha_border=true
+process/premult_alpha=false
+process/normal_map_invert_y=false
+process/hdr_as_srgb=false
+process/hdr_clamp_exposure=false
+process/size_limit=0
+detect_3d/compress_to=1
+svg/scale=1.0
+editor/scale_with_editor_scale=false
+editor/convert_colors_with_editor_theme=false

main.gd

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+extends Node3D
+
+var blobs = []
+var G = 0.1
+
+# Called when the node enters the scene tree for the first time.
+func _ready() -> void:
+	create_blobs()
+
+	for blob in self.blobs:
+		self.add_child(blob)
+
+# Called every frame. 'delta' is the elapsed time since the previous frame.
+func _process(delta: float) -> void:
+	calculate_gravity(delta)
+
+func calculate_gravity(delta: float) -> void:
+	for blob in self.blobs:
+		var accel: Vector3 = Vector3(0,0,0)
+
+		for other_blob in self.blobs:
+			if other_blob != blob:
+				var dist: Vector3 = other_blob.global_position - blob.global_position
+				accel += other_blob.mass * dist.normalized() / dist.length_squared()
+		blob.apply_central_impulse(G * blob.mass * accel * delta)
+
+func create_blobs() -> void:
+	var planetite: StandardMaterial3D = load("res://materials/planetite.tres")
+
+	var spacing = 2
+	var width = 5
+	var height = 3
+
+	self.blobs.append(Blob3D.new(planetite, Vector3(0,0,0), Vector3(0,0,0), 0.5, 50))
+	self.blobs.append(Blob3D.new(planetite, Vector3(0,0,4), Vector3(0,1,0), 0.2))
+	self.blobs.append(Blob3D.new(planetite, Vector3(0,0,-6), Vector3(0,-1.2,0), 0.3, 2))
+
+	#for z in range(width):
+	#	for y in range(height):
+	#		self.blobs.append(Blob3D.new(
+	#			planetite,
+	#			Vector3(
+	#				0,
+	#				spacing * (z - width/2),
+	#				spacing * (y - height/2),
+	#			)
+	#		))

main.gd.uid

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+uid://bvercqvetau4

main.tscn

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+[gd_scene load_steps=3 format=3 uid="uid://cgbep21nbp5lo"]
+
+[ext_resource type="Script" uid="uid://bvercqvetau4" path="res://main.gd" id="1_ig7tw"]
+[ext_resource type="Script" uid="uid://4wscni70so3k" path="res://camera_3d.gd" id="2_0xm2m"]
+
+[node name="Main" type="Node3D"]
+script = ExtResource("1_ig7tw")
+
+[node name="DirectionalLight3D" type="DirectionalLight3D" parent="."]
+transform = Transform3D(0.6706596, -0.47097108, 0.5730637, 1.870666e-08, 0.77256745, 0.63493276, -0.74176526, -0.42582372, 0.51812977, 3.5419807, 5.591663, 6.795337)
+
+[node name="Camera3D" type="Camera3D" parent="."]
+transform = Transform3D(-4.371139e-08, 0, 1, -0.0037873555, 0.99999285, -1.6555056e-10, -0.99999285, -0.0037873555, -4.3711076e-08, 65.657364, 0, 24.970047)
+script = ExtResource("2_0xm2m")

materials/orbit_dot.tres

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+[gd_resource type="StandardMaterial3D" format=3 uid="uid://dnxdmrh6a3kbi"]
+
+[resource]

materials/planetite.tres

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+[gd_resource type="StandardMaterial3D" format=3 uid="uid://b2picrcnsm0sm"]
+
+[resource]
+albedo_color = Color(0, 0, 1, 1)

node_3d.tscn

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+[gd_scene format=3 uid="uid://ba53hmyqs4tl2"]
+
+[node name="Node3D" type="Node3D"]

project.godot

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+; Engine configuration file.
+; It's best edited using the editor UI and not directly,
+; since the parameters that go here are not all obvious.
+;
+; Format:
+;   [section] ; section goes between []
+;   param=value ; assign values to parameters
+
+config_version=5
+
+[application]
+
+config/name="PlanetSim"
+run/main_scene="uid://cgbep21nbp5lo"
+config/features=PackedStringArray("4.5", "Forward Plus")
+config/icon="res://icon.svg"
+
+[physics]
+
+3d/physics_engine="Jolt Physics"
+3d/default_gravity=0.0
+3d/default_linear_damp=0.0
+3d/default_angular_damp=0.0