How to make a projectile differentiate between collision with the floor and with the wall in a tilemap layer?

[dairancaetano]

Hi, I’m a Godot beginner and I’m developing a 2D platformer. I’m currently trying to implement a projectile, a spear. The idea is for it to collide with the wall and create a platform. The problem is that when it collides with the ground, it also creates a platform. I tried using TileData to place a String in the block corresponding to the wall in the tilemap layer and thus try to create a detection for the spear, but I’m having trouble implementing it and I don’t even know if my idea makes sense. Do you have any guidance on how to do this?

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[gertkeno]

To get custom data from a TileMapLayer collision you have to find the tile, if you are using a CharacterBody2D for the spear you could check on move_and_collide

var collision := move_and_collide(velocity * delta)
if collision:
	var tilemap := collision.get_collider() as TileMapLayer
	if tilemap:
		var tile_coords := tilemap.get_coords_for_body_rid(collision.get_collider_rid())
		var tile_data := tilemap.get_cell_tile_data(tile_coords)
		if tile_data and tile_data.get_custom_data("Wall") == "Wall": # or use a boolean custom data
			make_platform()

If you do not want to assign “Wall” custom data to each wall you could use the collision normal instead.

var collision := move_and_collide(velocity * delta)
if collision:
    var dotup: float = collision.get_normal().dot(Vector2.UP)
    if absf(dotup) < 0.001: # or adjust 0.001 to the maximum wall angle
        make_platform()

[dairancaetano]

Thanks for the reply, I’m using a 2D Area for the spear, would that change the approach? I adjusted the Tilemap text to better match the sides.