Go, Go, Godot!
  • 0

Projectiles going through collision objects

October 27, 2022

Ever had the problem where you’re firing a bullet or some kind of projectile at high speeds, and it just goes right through the collision object, instead of hitting it?

Here’s a weapon that fires a bullet at random velocities, to demonstrate the issue:

The bullets impact the character in various places, rather than at the first point of contact. I haven’t found a way to enable any kind of continuous contact option, outside of playing with the safe_margin setting. I ended up adding a raycast:

The ray cast looks somewhat like this:

func _physics_process(delta):
	ttl -= delta
	match state:
		STATES.FIRED:
			var collision: KinematicCollision2D = move_and_collide(velocity * delta)
			if collision: _on_collision(collision.get_collider(), collision.get_position())
			
			var rq = PhysicsRayQueryParameters2D.create(_last_pos, position, collision_mask)
			rq.collide_with_areas = true
			var res: Dictionary = get_world_2d().direct_space_state.intersect_ray(rq)
			if res.has("collider"):
				_on_collision(res.collider, res.position)
				position = res.position
			elif ttl <= 0:
				state = STATES.EXPIRED
		# ...

It’s definitely a hack, though. The move_and_collide should be replaced by the ray query. Using both instructions together could result in an even weirder situation; move_and_collide could skip a collision object (the issue we’re trying to fix with the ray query), but then still collide with a different collision object. Then the ray query redoes the same movement and collides with the first object that was missed by move_and_collide . Depending on the game, that could mean something like randomly shooting through shields or walls under specific circumstances.

The current approach is essentially a two-pass solution, where the first pass is sloppy, and the second pass works as intended, but doesn’t move the projectile.

Posted in Godot.
Share
PreviousMaking videos for the web with Godot 4’s Movie Writer
NextAudio Manager to handle the loading of sound effects in bulk

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Related Posts

  • March 12, 2025

    Inventory System 2 Alpha 3 available

    This release improves weight management. Inventories can now configure an option weight limit, and item stacking and item transfer strategies are weight-aware. The crafting demo and crafting mechanic in the inventory tour have been improved. Auto-crafting is limited to the crafting slide, so that items don’t automatically and unexpectedly get crafted while stepping through the …

  • February 17, 2025

    Inventory System 2 Alpha 2 available

    This release contains the new Godot editor integrations. It offers an Item Library bottom panel that makes it easier to manage your inventory item types, and an inspector plugin that lets you edit items in a GGItemCollection. This also reduces the need for manually creating GGItemData resources, which simplifies item management at design time significantly. …

  • January 15, 2025

    Inventory System 2 Alpha 1 available

    The first alpha of the inventory system v2 is now available. For v2, a lot of refactoring work has been done with a focus on improving the developer experience. As part of that, the naming convention of the addon classes was streamlined and is more consistent now. The GDScript documentation comments have been improved significantly …

  • September 29, 2022

    Audio Manager to handle the loading of sound effects in bulk

    Years ago I purchased a game dev bundle on HumbleBundle. Part of that was a sound library called Pro Sound Collection. It’s pretty comprehensive, whether RPG or FPS, there are sounds for a ton of use cases. I might as well use them for something. Luckily for me, the sound collection is pretty well organized. …

    © 2026 GoGoGodot.io. All rights reserved.