ShapeCast2D sometimes doesn't detect collisions with RigidBody2Ds

[dragonaero]

SOLVED! Link to solution

Godot Version

v4.4.stable.steam [4c311cbee]

Question

I’m having trouble with ShapeCast2Ds not detecting RigidBody2Ds with CollisonPolygon2Ds.
Sometimes, the collision is detected; other times, it isn’t. Here are some instances where a collision is not detected (look to the left of the image):

(One thing I’ve noticed is that in all of these instances, the top-half of the shapecast is colliding with nothing and the bottom-half is colliding with part of a piece. Maybe that has something to do with the problem, but I’m not entirely sure.)

I’ve double checked both the ShapeCast2D and the RigidBody2D. The ShapeCast2D has masks 1 and 3; the RigidBody2D has layers 1 and 3 to match.

The intended result is that once the ShapeCast2D detects the piece, the piece is destroyed. That doesn’t happen in the image examples above; the enemy simply gets stuck.

Here’s are some video examples of a collision failing to be detected before being successfully detected by the addition of another RigidBody:

And here’s how I code the checks for RigidBody2Ds:

func _physics_process(delta: float) -> void:
    if front_shapecast.is_colliding():
        var collider = front_shapecast.get_collider(0)
        print(collider)
        #print(collider.get_class())
        if collider is Guy:
            collider.hurt(damage)
            death()
        elif collider is PieceBody: # <- This is what the ShapeCast2D should be colliding with
            collider.hp -= damage
            death()

Note that the ShapeCast2D is colliding with PieceBodys (the Tetris-looking RigidBody2Ds)

[dragonaero]

SOLUTION: I moved the ShapeCast2D to the right edge of the enemy (or left depending on the direction) and set its target position to (0, 0). Now it has no problems detecting collisions.

(Purple rectangle is the ShapeCast2D in question)

[OriginalBadBoy]

@dragonaero

var collider = front_shapecast.get_collider(0)

This will only ever get the 1st collision btw, if you need multiple collisions at once then that might also be a problem.