add debug drawing class

project.godot

@@ -23,6 +23,7 @@ config/icon="res://icon.svg"
 CursorManager="*res://scripts/globals/cursor_manager.gd"
 FullscreenManager="*res://scripts/globals/fullscreen_manager.gd"
 QuittingManager="*res://scripts/globals/quitting_manager.gd"
+DebugDraw="*res://scripts/globals/debug_draw.gd"
 
 [debug]
 
@@ -30,7 +31,6 @@ settings/crash_handler/message="Oh my, there's a BUG in the game! How queer and
 gdscript/warnings/untyped_declaration=2
 gdscript/warnings/unsafe_property_access=2
 gdscript/warnings/unsafe_method_access=2
-gdscript/warnings/unsafe_cast=2
 gdscript/warnings/unsafe_call_argument=2
 gdscript/warnings/integer_division=0
 
@@ -60,3 +60,8 @@ toggle_fullscreen={
 , Object(InputEventKey,"resource_local_to_scene":false,"resource_name":"","device":-1,"window_id":0,"alt_pressed":true,"shift_pressed":false,"ctrl_pressed":false,"meta_pressed":false,"pressed":false,"keycode":0,"physical_keycode":4194309,"key_label":0,"unicode":0,"location":0,"echo":false,"script":null)
 ]
 }
+toggle_debug={
+"deadzone": 0.5,
+"events": [Object(InputEventKey,"resource_local_to_scene":false,"resource_name":"","device":-1,"window_id":0,"alt_pressed":false,"shift_pressed":false,"ctrl_pressed":false,"meta_pressed":false,"pressed":false,"keycode":0,"physical_keycode":96,"key_label":0,"unicode":96,"location":0,"echo":false,"script":null)
+]
+}

scripts/globals/debug_draw.gd

@@ -0,0 +1,53 @@
+extends CanvasLayer
+
+var camera: Camera3D
+var control: Control = Control.new()
+
+var vectors_to_draw: Array[Dictionary] = []
+
+func _ready() -> void:
+	camera = get_viewport().get_camera_3d()
+	layer = 999
+	visible = false
+	control.draw.connect(_on_control_draw)
+	add_child(control)
+
+func _process(_delta: float) -> void:
+	if not visible:
+		return
+	control.queue_redraw()
+
+func _input(event: InputEvent) -> void:
+	if event.is_action_pressed("toggle_debug"):
+		visible = not visible
+		vectors_to_draw.clear()
+
+func vector(from: Vector3, to: Vector3, color: Color = Color(1, 0, 0)) -> void:
+	if not visible:
+		return
+
+	vectors_to_draw.append({"from": from, "to": to, "color": color})
+
+func _draw_vector(from: Vector3, to: Vector3, color: Color = Color.RED) -> void:
+	if not visible:
+		return
+
+	var start := camera.unproject_position(from)
+	var end := camera.unproject_position(to)
+	control.draw_line(start, end, color, 2)
+	_draw_triangle(end, start.direction_to(end), 5, color)
+
+func _draw_triangle(pos: Vector2, dir: Vector2, size: float, color: Color) -> void:
+	var a := pos + dir * size
+	var b := pos + dir.rotated(2 * PI / 3) * size
+	var c := pos + dir.rotated(4 * PI / 3) * size
+	var points := PackedVector2Array([a, b, c])
+	control.draw_polygon(points, PackedColorArray([color]))
+
+func _unproject(pos: Vector3) -> Vector2:
+	return camera.unproject_position(pos)
+
+func _on_control_draw() -> void:
+	for v in vectors_to_draw:
+		_draw_vector(v["from"] as Vector3, v["to"] as Vector3, v["color"] as Color)
+	vectors_to_draw.clear()

scripts/main_camera.gd

@@ -34,6 +34,8 @@ func _process(delta: float) -> void:
 	var offset_direction := Vector3.BACK.rotated(Vector3.RIGHT, rotation.x)
 	var offset := offset_direction * distance
 	position = target_position + offset
+	DebugDraw.vector(target_position, target_position + Vector3.UP)
+	DebugDraw.vector(Vector3.ZERO, Vector3.UP, Color.GREEN)
 
 func _input(event: InputEvent) -> void:
 	if event is InputEventMouseMotion: