Flying Enemy

Flying Enemy

System Summary

The Flying Enemy is a dynamic enemy type that moves between two points in space, a predictable traversal pattern for the player. Unlike Patrol enemies, Flying Enemies are not constrained to ground navigation and instead move freely in straight-line paths between two defined offsets.

Connected Systems

• Game Manager (handles reset / state transitions)
• Property Menu (modifies speed and movement offset)
• Entity Manager (spawning and saving enemies)
• Resource System (FlyingPreset .tres files)

Core Behavior

Flying Enemies:

• Move between two points (Point A and Point B)
• Reverse direction when reaching either endpoint
• Use direct velocity-based movement (no pathfinding)
• Ignore gravity
• Can collide with level geometry
• Damage or kill player on contact (via base enemy logic)
• Can be stomped by player

Feature Breakdown

Base Enemy Behavior (Inherited)

• Player can defeat enemy by jumping on top of it
• Player takes damage on side collisions
• Supports health system
• Uses shared enemy interface (Enemy.gd)

Flying Enemy Behavior

• Moves in a straight line between two points:
  • Point A = spawn position
  • Point B = Point A + Offset
• Automatically switches direction when reaching a point
• Uses normalized direction vector for smooth motion

Editor Properties

Flying Speed

Controls how fast the enemy travels between points.

• Higher values = faster movement

Point B Offset

Defines the second movement point relative to the spawn position.

• X controls horizontal distance
• Y controls vertical distance
• Supports diagonal movement

Example:

• Offset (256, 0) -> moves right
• Offset (0, -256) -> moves up
• Offset (256, 256) -> moves diagonally

Important Variables

Runtime Variables

Variable	Type	Description
propertyFile	Resource	Stores the currently assigned FlyingPreset resource
point_a	Vector2	Spawn position (set when enemy is placed)
point_b	Vector2	Calculated endpoint based on offset
target_point	Vector2	Current movement destination
speed	float	Movement speed of the enemy

Important Functions

assign_script(id: String, position: Vector2i) -> void

Assigns a FlyingPreset resource to the enemy based on a generated ID.

Purpose:

• Loads the correct .tres file from disk
• Assigns it to propertyFile
• Sets the enemy's identity in the editor system

apply_script(file: Resource) -> void

Applies a FlyingPreset resource to the enemy instance.

Purpose:

• Reads stored data from the resource
• Updates movement behavior based on saved values
• Recalculates patrol path (Point A and Point B)

Important:

• Does NOT reposition the enemy in world space
• Assumes enemy is already placed correctly by the editor

Movement Logic (How It Works)

1. Enemy spawns at Point A (editor placement)
2. Point B is calculated using offset: Point B = Point A + Offset
3. Enemy moves toward target point using normalized direction
4. When close enough to target:
   • Switches target to the opposite point
   • Repeats indefinitely

Data Flow

1. Editor places enemy
2. assign_script()
3. Resource created/saved (.tres)
4. apply_script() on load
5. Point A set = global position
6. Point B calculated = A + offset
7. Enemy begins patrol movement

Design Notes

Offset-based system was chosen instead of absolute coordinates to:

• Make enemy placement reusable
• Simplify editing in property menu
• Avoid dependency on world coordinates in resources

Movement is intentionally simple (no pathfinding) to ensure:

• Predictability for level design
• Easy debugging
• Low performance cost

Known Issues

• Very small offset values result in nearly invisible movement (must ensure slider range is sufficient)
• May stuck on props if approach at an unusual angle

Summary

The Flying Enemy is a simple but flexible enemy type designed for predictable linear movement. It is fully controlled through a resource-based system and integrates with the editor for real-time configuration.