chore: init

.gitattributes

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

.gitignore

@@ -0,0 +1,3 @@
+# Godot 4+ specific ignores
+.godot/
+/android/

LICENSE.txt

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2024 yusdacra
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -0,0 +1,17 @@
+# boid_2d
+
+Addon for Godot that adds a 2D node for simulating boids / flocking.
+
+![boids](./resources/boids.gif)
+
+## Usage
+
+Clone the repository and copy over the addon.
+Make an inherited scene from `boid.tscn`, add a `Sprite2D` (or whatever visuals you have) and instantiate and spawn many.
+Checkout the examples on how to use it more.
+
+## TODO
+
+- [ ] fix weird spasming behaviour
+- [ ] improve collision (dont only bounce, maybe follow wall in some conditions etc.)
+- [ ] improve performance (BoidManager autoload that tracks and manages every boid?)

addons/boid_2d/boid.gd

@@ -0,0 +1,121 @@
+extends Area2D
+class_name Boid
+
+
+## sets the `RayCast2D` used to detect walls.
+@export var wallcast: RayCast2D
+## sets the `Area2D` used for vision (seeing other boids).
+@export var vision: Area2D
+## sets the rotate timer, allowing boids to perform random rotations based on the timer's timeout signal.
+@export var rotate_timer: Timer
+
+@export_group("properties")
+## controls the target (max) speed.
+@export var target_speed := 6.0
+## controls how much other boids affect this boid.
+## higher values will make them more dispersed.
+@export var steer_away_factor := 40
+## controls whether or not to run collisions before running boid calculations.
+## enabling this can help reduce boids escaping colliders, especially if they are following something.
+@export var collide_first := false
+
+@export_group("follow")
+## controls which node to try and follow, if any
+@export var follow_point: Node2D
+## controls the radius at which the boid will target, instead of the target directly
+@export var follow_radius := 100.0
+
+var last_follow_pos: Vector2 = Vector2.ZERO
+var follow_target: Vector2
+var speed := target_speed
+var vel := Vector2.ZERO
+var boidsSeen: Dictionary = {}
+
+
+func _ready() -> void:
+	assert(wallcast, "boid invalid: wallcast (RayCast3D) not assigned")
+	assert(vision, "boid invalid: vision (Area2D) not assigned")
+	if rotate_timer:
+		rotate_timer.timeout.connect(_on_rotate_timer_timeout)
+
+
+func _physics_process(delta: float) -> void:
+	if collide_first:
+		_process_collision()
+		_process_boids()
+	else:
+		_process_boids()
+		_process_collision()
+	# move boid
+	var vel_dir := vel.normalized()
+	# fix if a boid stops by getting seperated and its vel being cancelled at the same time
+	if vel_dir.is_zero_approx(): vel_dir = Vector2.RIGHT
+	vel = vel_dir * speed
+	global_position += vel
+	# rotate boid
+	global_rotation = atan2(vel_dir.y, vel_dir.x)
+
+
+func _process_boids() -> void:
+	var numOfBoids := boidsSeen.size()
+	var avgVel := Vector2.ZERO
+	var avgPos := Vector2.ZERO
+	var steerAway := Vector2.ZERO
+	if numOfBoids > 0:
+		for boid: Boid in boidsSeen.values():
+			avgVel += boid.vel; avgPos += boid.global_position
+			var dist := boid.global_position - global_position
+			steerAway -= dist * (steer_away_factor / dist.length())
+	
+	# apply follow point vel
+	if follow_point:
+		var dist_to_follow := global_position.distance_to(follow_point.global_position)
+		if global_position.distance_to(follow_target) < 10.0 or dist_to_follow > follow_radius:
+			_calc_follow_target()
+		# slow down speed when nearing target
+		speed = maxf(0.0, lerpf(target_speed, 0.0, follow_radius / dist_to_follow))
+		var target_vel := (follow_point.global_position - last_follow_pos) * Engine.physics_ticks_per_second
+		avgVel += target_vel
+		avgPos += follow_target
+		var dist := follow_target - global_position
+		steerAway -= dist * ((steer_away_factor + follow_radius) / dist.length())
+		numOfBoids += 1
+		last_follow_pos = follow_point.global_position
+	
+	if numOfBoids > 0:
+		avgVel /= numOfBoids
+		vel += (avgVel - vel) / 2
+
+		avgPos /= numOfBoids
+		vel += avgPos - global_position
+
+		steerAway /= numOfBoids
+		vel += steerAway
+
+
+func _calc_follow_target() -> void:
+	var follow_vec := follow_point.global_position - global_position
+	var target_length := follow_vec.length() + follow_radius
+	follow_target = global_position + follow_vec.normalized() * target_length
+
+
+func _process_collision() -> void:
+	wallcast.force_raycast_update()
+	if not wallcast.is_colliding(): return
+	
+	var col_normal: Vector2 = wallcast.get_collision_normal()
+	vel = vel.bounce(col_normal)
+
+
+func _on_vision_area_entered(area: Area2D) -> void:
+	if area == self: return
+	boidsSeen[area.get_instance_id()] = area
+
+
+func _on_vision_area_exited(area: Area2D) -> void:
+	boidsSeen.erase(area.get_instance_id())
+
+
+func _on_rotate_timer_timeout() -> void:
+	vel -= Vector2(randf(), randf()) * speed
+	rotate_timer.start()

addons/boid_2d/boid.tscn

@@ -0,0 +1,34 @@
+[gd_scene load_steps=4 format=3 uid="uid://bq7s2yf0fohes"]
+
+[ext_resource type="Script" path="res://addons/boid_2d/boid.gd" id="1_xwhwb"]
+
+[sub_resource type="RectangleShape2D" id="RectangleShape2D_ackok"]
+size = Vector2(32, 16)
+
+[sub_resource type="RectangleShape2D" id="RectangleShape2D_ipkm3"]
+size = Vector2(60, 60)
+
+[node name="Boid" type="Area2D" node_paths=PackedStringArray("wallcast", "vision")]
+collision_mask = 0
+monitoring = false
+script = ExtResource("1_xwhwb")
+wallcast = NodePath("WallCast")
+vision = NodePath("Vision")
+
+[node name="CollisionShape2D" type="CollisionShape2D" parent="."]
+shape = SubResource("RectangleShape2D_ackok")
+
+[node name="WallCast" type="RayCast2D" parent="."]
+enabled = false
+target_position = Vector2(50, 0)
+
+[node name="Vision" type="Area2D" parent="."]
+collision_layer = 0
+monitorable = false
+
+[node name="CollisionShape2D" type="CollisionShape2D" parent="Vision"]
+position = Vector2(42, 0)
+shape = SubResource("RectangleShape2D_ipkm3")
+
+[connection signal="area_entered" from="Vision" to="." method="_on_vision_area_entered"]
+[connection signal="area_exited" from="Vision" to="." method="_on_vision_area_exited"]

addons/boid_2d/boid_2d.gd

@@ -0,0 +1,10 @@
+@tool
+extends EditorPlugin
+
+
+func _enter_tree() -> void:
+	add_custom_type("Boid2D", "Area2D", preload("boid.gd"), preload("boid_2d.svg"))
+
+
+func _exit_tree() -> void:
+	remove_custom_type("Boid2D")

addons/boid_2d/boid_2d.svg

@@ -0,0 +1,78 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!-- Created with Inkscape (http://www.inkscape.org/) -->
+
+<svg
+   width="16"
+   height="16"
+   viewBox="0 0 16 16.000001"
+   version="1.1"
+   id="svg1"
+   inkscape:version="1.3.2 (091e20e, 2023-11-25, custom)"
+   sodipodi:docname="boid_2d.svg"
+   inkscape:export-filename="..\..\resources\boid_2d.png"
+   inkscape:export-xdpi="768"
+   inkscape:export-ydpi="768"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:svg="http://www.w3.org/2000/svg">
+  <sodipodi:namedview
+     id="namedview1"
+     pagecolor="#ffffff"
+     bordercolor="#000000"
+     borderopacity="0.25"
+     inkscape:showpageshadow="2"
+     inkscape:pageopacity="0.0"
+     inkscape:pagecheckerboard="0"
+     inkscape:deskcolor="#d1d1d1"
+     inkscape:document-units="px"
+     showgrid="true"
+     inkscape:zoom="24.544781"
+     inkscape:cx="9.513224"
+     inkscape:cy="4.0538149"
+     inkscape:window-width="1858"
+     inkscape:window-height="1057"
+     inkscape:window-x="1912"
+     inkscape:window-y="-8"
+     inkscape:window-maximized="1"
+     inkscape:current-layer="layer1">
+    <inkscape:grid
+       id="grid1"
+       units="px"
+       originx="0"
+       originy="0"
+       spacingx="1"
+       spacingy="1.0000001"
+       empcolor="#0099e5"
+       empopacity="0.30196078"
+       color="#0099e5"
+       opacity="0.14901961"
+       empspacing="5"
+       dotted="false"
+       gridanglex="30"
+       gridanglez="30"
+       visible="true" />
+  </sodipodi:namedview>
+  <defs
+     id="defs1" />
+  <g
+     inkscape:label="Layer 1"
+     inkscape:groupmode="layer"
+     id="layer1">
+    <path
+       style="fill:#8da5f3;fill-opacity:1;stroke-width:26.4565;stroke-linejoin:bevel"
+       d="m 1,0.47939285 c 0,0 7,2.33333335 7,2.97323935 0,0.526761 -7,2.860094 -7,2.860094 2.333333,-2.333333 2.333333,-3.5 0,-5.83333335 z"
+       id="path1"
+       sodipodi:nodetypes="cscc" />
+    <path
+       style="fill:#8da5f3;fill-opacity:1;stroke-width:26.4565;stroke-linejoin:bevel"
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+       id="path2"
+       sodipodi:nodetypes="cscc" />
+    <path
+       style="fill:#8da5f3;fill-opacity:1;stroke-width:26.4565;stroke-linejoin:bevel"
+       d="m 2.4897504,9.4619873 c 0,0 7,2.3333327 7,2.9732387 0,0.526761 -7,2.860095 -7,2.860095 2.333333,-2.333334 2.333333,-3.500001 0,-5.8333337 z"
+       id="path3"
+       sodipodi:nodetypes="cscc" />
+  </g>
+</svg>

addons/boid_2d/boid_2d.svg.import

@@ -0,0 +1,38 @@
+[remap]
+
+importer="texture"
+type="CompressedTexture2D"
+uid="uid://c32akbxu1rkj8"
+path="res://.godot/imported/boid_2d.svg-172f46790795ecd4cef523288fe60368.ctex"
+metadata={
+"has_editor_variant": true,
+"vram_texture": false
+}
+
+[deps]
+
+source_file="res://addons/boid_2d/boid_2d.svg"
+dest_files=["res://.godot/imported/boid_2d.svg-172f46790795ecd4cef523288fe60368.ctex"]
+
+[params]
+
+compress/mode=0
+compress/high_quality=false
+compress/lossy_quality=0.7
+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/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=true
+editor/convert_colors_with_editor_theme=true

addons/boid_2d/plugin.cfg

@@ -0,0 +1,7 @@
+[plugin]
+
+name="Boid2D"
+description="Addon for implementing boids / flocking in Godot."
+author="yusdacra"
+version="0.1"
+script="boid_2d.gd"

examples/boid_2d/example_boid.svg

@@ -0,0 +1,65 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!-- Created with Inkscape (http://www.inkscape.org/) -->
+
+<svg
+   width="48"
+   height="24"
+   viewBox="0 0 48 24.000001"
+   version="1.1"
+   id="svg1"
+   inkscape:version="1.3.2 (091e20e, 2023-11-25, custom)"
+   sodipodi:docname="example_boid.svg"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:svg="http://www.w3.org/2000/svg">
+  <sodipodi:namedview
+     id="namedview1"
+     pagecolor="#5d6c8e"
+     bordercolor="#000000"
+     borderopacity="0.25"
+     inkscape:showpageshadow="2"
+     inkscape:pageopacity="0.0"
+     inkscape:pagecheckerboard="0"
+     inkscape:deskcolor="#d1d1d1"
+     inkscape:document-units="px"
+     showgrid="true"
+     inkscape:zoom="17.355781"
+     inkscape:cx="20.886412"
+     inkscape:cy="8.3833737"
+     inkscape:window-width="1858"
+     inkscape:window-height="1057"
+     inkscape:window-x="1912"
+     inkscape:window-y="-8"
+     inkscape:window-maximized="1"
+     inkscape:current-layer="layer1">
+    <inkscape:grid
+       id="grid1"
+       units="px"
+       originx="0"
+       originy="0"
+       spacingx="1"
+       spacingy="1"
+       empcolor="#0099e5"
+       empopacity="0.30196078"
+       color="#0099e5"
+       opacity="0.14901961"
+       empspacing="5"
+       dotted="false"
+       gridanglex="30"
+       gridanglez="30"
+       visible="true" />
+  </sodipodi:namedview>
+  <defs
+     id="defs1" />
+  <g
+     inkscape:label="Layer 1"
+     inkscape:groupmode="layer"
+     id="layer1">
+    <path
+       style="fill:#ffffff;stroke-width:22.677;stroke-linejoin:bevel"
+       d="M 48,12 C 48,-4.9999998e-7 0,0 0,0 c 30,9.9999996 30,14.999999 0,23.999999 0,0 48,0 48,-11.999999 z"
+       id="path1"
+       sodipodi:nodetypes="sccs" />
+  </g>
+</svg>

examples/boid_2d/example_boid.svg.import

@@ -0,0 +1,37 @@
+[remap]
+
+importer="texture"
+type="CompressedTexture2D"
+uid="uid://rk5u1wthr0n0"
+path="res://.godot/imported/example_boid.svg-ebae3589d3b59182aead052ab0bb5c16.ctex"
+metadata={
+"vram_texture": false
+}
+
+[deps]
+
+source_file="res://examples/boid_2d/example_boid.svg"
+dest_files=["res://.godot/imported/example_boid.svg-ebae3589d3b59182aead052ab0bb5c16.ctex"]
+
+[params]
+
+compress/mode=0
+compress/high_quality=false
+compress/lossy_quality=0.7
+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/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=6.0
+editor/scale_with_editor_scale=false
+editor/convert_colors_with_editor_theme=false

examples/boid_2d/example_boid.tscn

@@ -0,0 +1,15 @@
+[gd_scene load_steps=3 format=3 uid="uid://bcyffgnn2ahl3"]
+
+[ext_resource type="PackedScene" uid="uid://bq7s2yf0fohes" path="res://addons/boid_2d/boid.tscn" id="1_825c0"]
+[ext_resource type="Texture2D" uid="uid://rk5u1wthr0n0" path="res://examples/boid_2d/example_boid.svg" id="2_qfbgc"]
+
+[node name="Boid" instance=ExtResource("1_825c0")]
+collision_layer = 2
+
+[node name="Vision" parent="." index="2"]
+collision_mask = 2
+
+[node name="Sprite2D" type="Sprite2D" parent="." index="3"]
+position = Vector2(-2.17226e-06, 2.38419e-07)
+scale = Vector2(0.111111, 0.111111)
+texture = ExtResource("2_qfbgc")

examples/boid_2d/follow/example.gd

@@ -0,0 +1,18 @@
+extends Node2D
+
+
+func _ready() -> void:
+	for i in 40: spawnBoid()
+
+
+func _process(delta: float) -> void:
+	$Path2D/PathFollow2D.progress_ratio += delta * 0.1
+
+
+func spawnBoid() -> void:
+	var boid: Boid = preload("../example_boid.tscn").instantiate()
+	var screensize := get_viewport_rect().size
+	boid.modulate = Color(randf(), randf(), randf(), 1)
+	boid.global_position = Vector2((randf_range(200, screensize.x - 200)), (randf_range(200, screensize.y - 200)))
+	boid.follow_point = $Path2D/PathFollow2D
+	add_child(boid)

examples/boid_2d/follow/example.tscn

@@ -0,0 +1,19 @@
+[gd_scene load_steps=3 format=3 uid="uid://ckc0dhvrksfh4"]
+
+[ext_resource type="Script" path="res://examples/boid_2d/follow/example.gd" id="1_cb4mx"]
+
+[sub_resource type="Curve2D" id="Curve2D_ncwi0"]
+_data = {
+"points": PackedVector2Array(69.2957, 57.9564, -69.2957, -57.9564, 1117, 34, 79.375, -118.433, -79.375, 118.433, 34, 28, -61.7361, -114.653, 61.7361, 114.653, 22, 624, -42.8373, 69.2957, 42.8373, -69.2957, 1126, 622, 66.7758, 73.0754, -66.7758, -73.0754, 1117, 34)
+}
+point_count = 5
+
+[node name="Example" type="Node2D"]
+script = ExtResource("1_cb4mx")
+
+[node name="Path2D" type="Path2D" parent="."]
+curve = SubResource("Curve2D_ncwi0")
+
+[node name="PathFollow2D" type="PathFollow2D" parent="Path2D"]
+position = Vector2(1117, 34)
+rotation = -2.44507

examples/boid_2d/simple/example.gd

@@ -0,0 +1,13 @@
+extends Node2D
+
+
+func _ready() -> void:
+	for i in 100: spawnBoid()
+
+
+func spawnBoid() -> void:
+	var boid: Boid = preload("../example_boid.tscn").instantiate()
+	var screensize := get_viewport_rect().size
+	boid.modulate = Color(randf(), randf(), randf(), 1)
+	boid.global_position = Vector2((randf_range(200, screensize.x - 200)), (randf_range(200, screensize.y - 200)))
+	add_child(boid)

examples/boid_2d/simple/example.tscn

@@ -0,0 +1,12 @@
+[gd_scene load_steps=2 format=3 uid="uid://op0qicvpbjt6"]
+
+[ext_resource type="Script" path="res://examples/boid_2d/simple/example.gd" id="1_3gcrf"]
+
+[node name="Example" type="Node2D"]
+script = ExtResource("1_3gcrf")
+
+[node name="StaticBody2D" type="StaticBody2D" parent="."]
+collision_priority = 4.0
+
+[node name="CollisionPolygon2D" type="CollisionPolygon2D" parent="StaticBody2D"]
+polygon = PackedVector2Array(1152, 0, 1152, 648, 0, 648, 0, 0, 1088, 0, 1088, 64, 64, 64, 64, 576, 1088, 576, 1088, 0)

project.godot

@@ -0,0 +1,24 @@
+; 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="Boid Addon"
+run/main_scene="res://examples/boid_2d/simple/example.tscn"
+config/features=PackedStringArray("4.3", "GL Compatibility")
+
+[editor_plugins]
+
+enabled=PackedStringArray("res://addons/boid_2d/plugin.cfg")
+
+[rendering]
+
+renderer/rendering_method="gl_compatibility"
+renderer/rendering_method.mobile="gl_compatibility"

resources/boid_2d.png.import

@@ -0,0 +1,34 @@
+[remap]
+
+importer="texture"
+type="CompressedTexture2D"
+uid="uid://cp6l2f1oac4ce"
+path="res://.godot/imported/boid_2d.png-b56b7a427c09dbbdb1e601cb745d4254.ctex"
+metadata={
+"vram_texture": false
+}
+
+[deps]
+
+source_file="res://resources/boid_2d.png"
+dest_files=["res://.godot/imported/boid_2d.png-b56b7a427c09dbbdb1e601cb745d4254.ctex"]
+
+[params]
+
+compress/mode=0
+compress/high_quality=false
+compress/lossy_quality=0.7
+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/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